Archive for the 'General' Category

25
Feb
18

Dismantling a hard drive

Note that in the following post I’m describing taking a hard drive apart in order to reuse some of the parts, but have no intention of putting it back together, or making it work again as a hard drive!

This the 3.5″ hard drive I took apart as my first experiment:

Front & Back IMG_1515

I’m sorry the PCB side is rather blurry, but I was less interested in that than what was inside.

The tools required for the job were a small screwdriver set, from which I mostly used a Torx or ‘star’, which I think was size 8, and a very small Philips or crosshead for a couple of screws inside:

Tools IMG_1525

I also needed a large flat-bladed screwdriver, which I used two or three times.  If you’re going to do the same, you may find a few differences in the details – type and positioning of screws, differently shaped fittings, and so forth, but the principles should be the same.

I first removed the circuit board, and put that aside.  Turning it over, you can clearly see in the first picture the 6 screws round the edge of the ‘lid’ which needed removing.

Having taken these out, it seemed that the top was glued in place as well as screwed, so I went round with the large screwdriver, prying it open.  This almost freed it, but it was only after still experiencing considerable difficulty in getting it completely open that I realised there must be another screw somewhere in the middle, under the label.  I scraped away the label until I found it and took it out.  The arrow shows where it was.

Top IMG_1527

I was then able to take the lid right off and expose the inner workings – of which there aren’t actually that many.

Top removed Captioned IMG_1528

The picture shows the disk or disks, one on top of the other, like a stack of pancakes – except there are gaps between them, and the arm is actually several arms, one for each disk; the arm itself with the delicate heads on the end which read the data from the disks, and with its other end moving between two magnets (not visible at the moment); and finally a flexible plastic multi-way ‘cable’ which joins the arm – and some small circuitry on the arm – to a connector.  This would have poked through a gap in the case to connect to the circuit board  on the other side.

Later on, connections will have to made to some very, very tiny points on the arm, and it’s going to be a lot easier to trace these points back to the connector, so its important not to damage the plastic cable.  The connector could be poked out from the other side, once it two fixing screws had been removed.

The fitting obscuring the back end of the arm wasn’t – in this model of drive anyway – screwed in place, it was just slotted on some pins and just needed prising off.  I believe the magnets in hard drives are made of neodymium.  This is classed as a ‘rare earth’ (although it’s isn’t actually any rarer than, say, copper) and makes very strong magnets.  Just be a bit careful as you remove them, and think where you’re going to put them down as you can be surprised at how firmly they grab lighter metal objects.

This picture shows the top magnet fitting removed:

Top Magnet Out Captioned IMG_1529

Once the top magnet is off, it’s possible to move the arm out of the way and get the disks out.  This involves removing 6 screws around the centre (on top of the motor) and two screws at the side. the disks and the various fittings associated with them all come off in layers.  The disks – there were three of them in this drive, look very much like CD’s, with a large hole in the middle, except they’re made of metal.

I put the disks carefully to one side – I had an idea they might be good for chimes or cymbals – and focused on the arm.

With the top magnet out of the way, it was possible to see the so-called ‘voice’ coil’.  Two impossibly tiny wires connected the voice coil with the arm actuation circuitry, and to test that the arm was working I needed to attach a battery to these wires.

In the end these wires were just too small, so I traced them back through the plastic cable to the connector, where it was slightly easier to get at them.  Attaching the battery leads to the two points produced nothing at 4.5v, but at 9v there was a loud and satisfying clunk, which showed that the arm was working fine.

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The procedure with the next disk I worked on, a smaller 2.5″ was exactly the same.  The top came off once I had removed the 6 visible screws and the 7th screw hidden under the label.  I needed a smaller Torx/star screwdriver – a size 5 or 6 – for this disk compared to the other one.

1_IMG_1555

This exposed the single disk and arm:

2_IMG_1557

A single screw in the middle of the motor housing allowed the disk to come out.

3_IMG_1558

Removing two screws freed the unit in the bottom right, which connected the arm with the circuit board on the other side.

4_IMG_1559

I prised off the top magnet (bottom left), just to make sure the construction was the same as the 3.5″ drive – which it was.

I replaced the magnet and tested the drive with a battery.  I’d already removed a plastic retainer on the right, by the heads at the end of the arm; I also had to remove the plastic piece which you can see on the left, which was restricting the arm’s movement.  However, once I had done this, applying 9v to the appropriate pins on the connector reliably operated the arm.

In fact, this smaller mechanism would also work with 4.5v, which was a useful discovery.  If parts of the circuitry which would operate it had to be quite low – say, 5v – it could be handy if the arm would also work at the same voltage.

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So, I had verified that an arm from an inexpensive broken hard drive could operate as an electrically-operate striker, like a solenoid; that arms from both 3.5″ and 2.5″ drives would work; that the 3.5″ drive arm would operate at 9v; and the 2.5″ drive arm would operate at 4.5v.  It will be some time before I get round to the next part of this project, but the next thing will be to see how the arms could be set up to operate outside the hard drive housing.

25
Feb
18

Inductor pickups 1

After looking into piezo elements and electret microphones, I decided to try another kind of pickup described by Nic Collins, the magnetic inductor.

Collins describes using a device marketed as a telephone pickup coil – I don’t know what the situation is now, but it used to be illegal to attach recording devices directly to the telephone network, so a telephone pickup coil has a suction cup on one end to stick to the telephone handset, and a 3.5mm mono plug on the other end to connect to an amplifier or recording device.

I bought a few of these for about £1.50 each from CPC.

I wanted to see what was inside, so I sawed the top off one of them and took out the contents of the plastic enclosure.

It appeared to be a simple inductor coil, rather like a small guitar pickup, but with no indication of its value.

Inductors are the the third ‘passive linear circuit elements that make up electronic circuits,’ (https://en.wikipedia.org/wiki/Inductor) along with resistors and capacitors.  Their values are expressed in Henries (H), although 1 Henry is quite a large value and the the majority of inductors encountered in circuits fall in the millihenry (mH) range.

I was expecting to find other components inside the telephone coil enclosure, having read here: http://hydrophones.blogspot.co.uk/2010/09/induction-coil-pick-up-now-available.html that ‘whilst most other coils on the open market have certain limitations placed upon them, these adapted coils [for sale on that site] can detect a wider range of sounds that the technology is capable of . . . adapting the coils not only increases the range of frequencies but also boosts the overall signal level.’  There was no further information about the nature of the limiting circuitry, or the means of boosting the signal level, but perhaps the coils I bought were not the type with limitations, I couldn’t tell.

Nor could I tell what value of inductor could perform the function of the telephone coil.  An article here: http://www.unterzuber.com/tap.html on how to make a telephone coil recommends 100 turns of 28AWG wire on ferric core; another here: http://www.circuitstoday.com/telephone-pickup-preampliifer (sic) recommends 3000 – 5000 turns of 0.4mm on a plastic former.

There is a company called Knowles, which manufactures ‘telecoils’: inductors which can be built into hearing aids to amplify sounds created by an induction loop (http://www.knowles.com/eng/Products/Hearing-aid-components-accessories/Telecoils).  However, these are rare and quite expensive (£2 – £7 each from a component supplier with a minimum order requirement and delivery cost – more than the Telephone Pickup itself).  The values of these covered a very wide range, from about 30mH to over 900mH.

So, in order to experiment, I first had the coil from the Telephone Pickup.  I also bought some smaller inexpensive inductors of different values.  These were (on the left) 100mH, costing a little under 40p each, and (on the right), different values between 1mH and 10mH, costing a little under 4p each.

I also had a guitar pickup, which works on exactly the same principle, as mentioned above, but has 6 separate magnetic poles within it.  This was about £2:

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The preamp I had used recently for the electret micophones seemed to work fine, so I used this and experimented with the various different inductors, passing them over my laptop keyboard, a good source of magnetic noise.

These were the 3 inductors I compared: the Telephone Pickup Coil is on the left, the 100mH in the middle, and the 10mH on the right.

This is what they sounded like, running over the same small area of the laptop keyboard (the most interesting section!):

It seemed to me that the Telephone Pickup Coil was the most sensitive; the 100mH a little less sensitive, but still effective –  perhaps more effective in some areas where there was a great deal of noise; and the 10mH was a little too insensitive.  On balance, I thought the Telephone Coil was probably the one to use in a best quality application, but the 100mH would be fine in cases where cost was a major factor.

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For the next round of experiments I made some stereo inductor pickups: in one case I took the coil out of a second Telephone Pickup and hot glued a pair of them to a shaped piece of scrap acrylic; in the other I mounted two 100mH inductors side by side to a smaller acrylic strip.  I also tried out the standard-sized guitar pickup.

These three pickups were a great improvement on the single inductor pickups, and sounded like this, with the guitar first, then the stereo Telephone Coils, then the stereo 100mH inductors:

I had to be careful with the guitar pickup, as  bringing it near the laptop seemed to cause strange effects – the screen going blank, for example, which was not good . . . However, this wouldn’t be a danger in the application I hand in mind for it.

In fact, I would recommend NOT experimenting with a guitar pickup like this.  Because of the magnets in it, it could possibly damage sensitive circuits like laptops, mobile phones, etc. – stick to the passive inductors, like the other ones I used.

In the next post in this series, I will describe an instrument I made based on inductor pickups.

20
Jan
18

Electret microphones Pt 1- General

After starting my recent piezo project, I decided to look into electret microphones – there are many situations in which a piezo-type contact mic is less suitable than a mic which detects sounds in the air.

Electret capsules are very cheap, and need just a few additional components to get them to work.  I bought a number of these for about 10p – 11p each:

It’s possible to get them without any wires – long or short – attached, but I preferred these.  The smaller ones, illustrated at the top, were very small – 4mm in diameter; the larger ones were 10mm.  I also bought a few that were in between, at 6.5mm.

Most people working in electronic music will be aware of the importance of microphones, and  I have some quite expensive ones for different amplifying and recording purposes; but there are various situations in which a very low-cost method of picking up and amplifying sometimes quite small sounds can be all that’s needed.

One renowned electronic music composer for whom the microphone became extremely important for a time was Karlheinz Stockhausen.

In summer 1964, Stockhausen said, ‘I searched for ways to compose – flexibly – also the process of microphone recording. The microphone, used until now as a rigid, passive recording device to reproduce sounds as faithfully as possible, would have to become a musical instrument and, on the other hand, through its manipulation, influence ALL the characteristics of the sounds . . .’

At the same time, he had been experimenting with a large tam-tam (a percussion instrument very similar to a gong), ‘using a great variety of implements – of glass, cardboard, metal, wood, rubber, plastic – which I had collected from around the house.’

‘One day’, he continues, ‘I took some equipment from the WDR Studio for Electronic Music home with me. My collaborator Jaap Spek helped me. I played on the tam-tam with every possible utensil and during this, moved the microphone above the surface of the tam-tam. The microphone was connected to an electrical filter whose output was connected to a volume control (potentiometer), and this in turn, was connected to amplifier and loudspeaker. During this, Jaap Spek changed the filter settings and dynamic levels, improvising. At the same time, we recorded the result on tape.

‘The tape recording of this first microphony experiment constitutes for me a discovery of utmost importance . . . Actually, this moment was the genesis of a live electronic music with unconventional music instruments. On the basis of this experiment I then wrote the score of Mikrophonie I. Two players excite the tam-tam using a great variety of implements, two further players scan the tam-tam with microphones . . . Two further players – seated in the auditorium at the left and right of the middle – each operate an electrical filter and two potentiometers. They, in turn, reshape the timbre and pitch . . . dynamic level and spatial effect . . . and the rhythm of the structures . . .’

The score includes instructions for the placing and movement of the microphones, just as it includes instructions for the tam-tam players and the filter operators, so the microphones can be regarded as essential instruments in the performance of the piece.

One of the interesting features of the use of microphones in the piece is, as Stockhausen wrote: ‘normally inaudible vibrations (of a tam-tam) are made audible by an active process of listening into [them with a microphone].’ The reviewer Albrecht Moritz (http://home.earthlink.net/~almoritz/mikrophonie1.htm) states: ‘There are several passages in Mikrophonie I where this process is exclusively employed, foregoing stronger excitement of the tam-tam which would produce the commonly heard sounds. A result is that, if you would play back these passages to persons whom you would leave in the dark about the source of the sounds, probably most or even all of those listeners – including musicians – would not be able to guess it.’

Elsewhere Moritz says that ‘the audibility of most sounds that are created on the tam-tam in Mikrophonie I appears to strictly depend on the microphonic amplification. Among these are scratching noises, produced by treating the surface with not only metallic, but also other kinds of objects. Strangely “rolling” sounds can be generated on the surface, sounds evocative of rustling of silver paper, and many other astounding sounds . . . Quite frequently there are dark, roaring, sometimes growling, yet in volume often rather soft, undercurrents of sound that appear to stem from only local resonances of the tam-tam plate, generated by gentle use of a beater or as a result of other treatment, a sound phenomenon most likely audible only because of microphonic amplification as well.’

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These electret capsules won’t work, however, just by connecting them to a mixer or amplifier – they have a small built-in preamp inside them which needs power to operate it.  This means the positive lead to the capsule must have a few volts of power running to it – 3v to 9v, typically – for the capsule to work.   An interesting article on this topic can be found at http://www.epanorama.net/circuits/microphone_powering.html.

The minimum circuitry required to get a sound from the capsule is this:

Using a prototype of this circuit with the Taurus amplifier, the level of the signal was perfectly good enough without any additional circuitry.

Sometimes, however, more output is needed, and I found a suitable circuit which was simple but effective at http://www.instructables.com/id/Pre-amp-to-electret-mic/.  It was based on a single transistor, a 2N3904, obtainable at less than 5p each by buying a bag of 50, plus 3 resistors and 2 capacitors.   The circuit for one channel looked like this:

I made up a batch of them all at the same time on a spare piece of veroboard.  These 12 circuits cost no more than about £2 – £2.50 altogether.

I took some of these and made up some stereo circuits, adding an output socket, 9v battery clip and volume control pot to each one:

With this I was able to experiment with different microphone combinations. No other components were needed, except the electret capsules themselves.  In some cases I connected the two wires from the capsule directly to input and ground on the board, at other times I attached input sockets.

In all cases I was surprised at the quality of the sound I was able to get for such a low cost.  The circuit also worked with the piezo mics/pickups I had made earlier, although the output didn’t seem to have as much lower frequency content.

In the next article in the series I’ll describe some of the practical applications for which I used these electrets.

 

 

25
Nov
17

Piezos Pt 1 – General

Piezos, Piezo Sensors, Piezo Transducers, or Piezo Elements are small, cheap components that can be useful in several different ways to the electronic musician.  I had some ideas for ways I’d like to use them, and this series will describe some projects in which piezo elements were employed.

A transducer is a device which changes energy from one form to another – for example, tape heads and record pickup cartridges are transducers as they change magnetic signals on the tape or movement in the grooves of a record into electrical signals; microphones and speakers are transducers because in the first case they change movement in the air into electrical signals , or in the other they change electrical signals into movement in the air.

Piezo elements are transducers because they can transform physical movement into electrical signals like a pickup cartridge, or electrical signals into movement in the air like a speaker.  They do this not by sensing magnetic fields, like a tape head or guitar pickup, but by the movement of crystals, and this is what a piezo element has inside it.

Piezos work especially well when attached to something which will vibrate and produce electrical signals which can be amplified, or can amplify the vibration of signals fed into it.

In everyday life, they’re usually found in mobile phones, in buzzers or in place of speakers in smaller children’s toys.  This gives a clue as to the different ways in which they can be employed in electronic music circuits: as microphones, as speakers, or as triggers for switches.

Much of the information below was gleaned from Nic Collins’ book Handmade Electronic Music, and his series of videos on YouTube called Hack of the Month Club.

First of all, this is what piezo elements look like if you buy them from a components supplier, or take one out of a phone or musical toy:

or sometimes like this, if they come in the form of a sounder or buzzer – in this case, the element can be carefully removed from the plastic surround.

They vary in diameter from 10mm to 50mm.  I have used some of the smaller ones, but most of the ones I have are 18 or  20mm, and 27 or 35mm.

[Edit: I have usually got the best sound out of the larger diameter ones, so these are the ones I use for preference, unless space dictates a smaller one has to be employed.  This means I usually choose the 35mm, which cost quite a bit less than the 50mm ones; but I’ve occasionally used the 50mm ones for special purposes].

When I buy them, I prefer the ones with the leads already soldered on.  This saves a job – and it’s quite tricky to do the soldering effectively – and they’re still very cheap.  The last batch I bought worked out at about 12p each for the 35mm diameter ones, and just 6p each for the 18mm ones.

Perhaps the first piece of music to use transducers in its realisation was Cartridge Music by John Cage, composed and first performed in 1960. As described on the webite of the John Cage Trust: ‘The word ‘Cartridge’ in the title refers to the cartridge of phonographic pick-ups, into the aperture of which is fitted a needle. In Cartridge Music, the performer is instructed to insert all manner of unspecified small objects into the cartridge; prior performances have involved such items as pipe cleaners, matches, feathers, wires, etc. Furniture may be used as well, amplified via contact microphones. All sounds are to be amplified and are controlled by the performer(s).’

Another composer who famously used transducers was David Tudor. Tudor – who was closely associated with John Cage – created a piece called Rainforest – originally in the mid 1960’s, but it went through a number of changes during the rest of the decade as Tudor’s techniques and equipment developed. The piece was based on the idea of making objects other than speakers vibrate, picking up the sounds they made with microphones and then filtering and mixing the resultant sounds.

‘My piece Rainforest IV‘, Tudor explained, ‘was developed from ideas I had as early as 1965. The basic notion, which is a technical one, was the idea that the loudspeaker should have a voice which was unique and not just an instrument of reproduction, but as an instrument unto itself . . .’

‘. . . I eventually acquired some devices called audio transducers. They were first developed for the US Navy because they needed a device which could sound above and under the water simultaneously . . . I had them in 1968 when MC [choreographer Merce Cunningham] asked me for a dance score and I decided that I would try to do the sounding sculpture on a very small scale. I took these transducers and attached them to very small objects and then programmed them with signals from sound generators. The sound they produced was then picked up by phono cartridges and then sent to a large speaker system.’

‘Several different versions of this piece were produced. In 1973 I made Rainforest IV where the objects that the sounds are sent through are very large so that they have their own presence in space. I mean, they actually sound locally in the space where they are hanging as well as being supplemented by a loudspeaker system. The idea is that if you send sound through materials, the resonant nodes of the materials are released and those can be picked up by contact microphones or phono cartridges and those have a different kind of sound than the object does when you listen to it very close where it’s hanging. It becomes like a reflection and it makes, I thought, quite a harmonious and beautiful atmosphere, because wherever you move in the room, you have reminiscences of something you have heard at some other point in the space.’

(from An Interview with David Tudor by Teddy Hultberg in Dusseldorf, May 17-18, 1988, http://davidtudor.org/Articles/hultberg.html).

A reviewer present at a performance of Rainforest described the appearance and sound of the piece as follows: ‘The entire piece sounds at first like an ethereal insect chorus, but the layers gradually disperse into patterns of jagged counterpoint, which in the performance seemed to harmonize perfectly with the movements of the dancers . . .

‘Most of the sounds are created by sine tones being reverberated through a forest of suspended metal containers, pieces of junk that function as “biased” loudspeakers imparting their own timbral colouration to the sounds which pass through them. These sounds are picked up by contact microphones, fed back into Tudor’s mixing and filtering controls, and then recycled back into the expanding forest of increasingly hybrid noises. The array of metal containers usually fills an entire gallery, and spectators are invited to walk around and put their heads inside the containers.’

(Roger Sutherland, Musicworks, Number 75, Fall 1999, http://moderecords.com/catalog/064tudor.html)

Some modern performances of Cartridge Music will use piezo elements instead of cartridges, although this might be considered cheating. Piezos, on the other hand, are ideal for achieving the kinds of effects employed by Tudor in Rainforest, and the different projects I planned with them will hopefully cover these uses and more.

Part 2 of this series of articles is here.

 

 

06
Nov
13

Notes on game controllers

I decided to write this post just to tie together some of my experiences of using game controllers of various sorts to make music.

Generic USB controllers like these are generally pretty easy to use:

Game Controller 3

StyloSim6sm

Since computers come with USB ports on them, it’s usually just a case of plug them in and get going.  There are lots of them about and they can be picked up cheaply on eBay and Gumtree or from local charity shops.

The main consideration is what program to use which can interpret the signals the controller is sending out and allow you to use those signals for your own purposes.  There are many of these, ranging from simple apps to tweak the operation of a particular device, to large and complex  programs designed to customise a device’s every action to the user’s requirements.

This is made possible by the existence of the ‘HID’ standard for USB devices.  HID = ‘Human Interface Device’, a description which can be used to cover devices such as computer keyboards, mice, game controllers, joysticks, and the like – all the things which humans use to interact with computers.  As long as the device is made to conform to the standard – and manufacturers have readily got used to the idea of doing so – these programs can interpret the input and make it available to be changed to a different input; to perform an action completely unrelated to the device’s original purpose; or send data to another program which can use it creatively.

I’ve used several of these for different purposes.  There’s Multicontrol, which I used for this MIDI Drum controller:

MultiControlDrums1

Multicontrol has the ability to interpret the game controller’s signals and pass them on in the form of MIDI messages, or OSC (Open Sound Control).  Designed by Alexander Refsum Jensenius, it’s distributed free for Mac OS.  There is a source file downloadable from the site referenced above, although I have no idea if this can be compiled for Windows PC’s.

I’ve also used a commercial program, ControllerMate, which enables very sophisticated interpretation of controller signals.  This allows not only for simple button ‘mapping’, where you specify, for example, keystrokes for each controller button, but also, with this window you can build up complicated series of events, initiated by a button press.:

ControllerMate window

The small drop-down list to the right indicates the wide variety of actions that can be incorporated into the instructions for each button or other control.

The list in the left-hand column indicates a couple of devices which I’ve made customised groups of special controls for: once you’ve set the controls up, you can save them and call them up by name.  It’s possible in this way to have several different set-ups for the same device, depending on what you want to use it for at different times.

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My favourite program is PureData, or Pd for short.  Using Pd means you have to write the programs yourself – but this is done graphically, rather in the manner of flow-charts, rather than by writing lines of code, and the program is specifically designed for making music, so it has typical audio and MIDI functions (Pd calls them ‘objects’) ready to use.

I’ve used Pd both for creating instruments, like the Theresynth, which uses the PCLine Rumble Pad pictured above, and for sound and sample manipulation.  The blog post for the Theresynth (which uses one of the joysticks on the controller for changing pitch in a way reminiscent of a theremin), also has quite a detailed description of the Pd programming.  I’ve also blogged about various sound manipulation apps (or ‘patches’) in the past, including the StyloSim, which uses the joystick controller pictured above, and the Black Widow.

The StyloSim patch isn’t very extensive, and looks like this:

StyloSim2

The small box with ‘hid’ in it, near the top right-hand corner, is the Pd object which recognises input in the HID standard; the ‘route’ objects below split up the different inputs, and then you can send them off to do whatever you need them to do – control oscillators or filters, perform mathematical functions, create MIDI messages, and so on.

While on the subject of software, a handy piece of freeware which I often use is Joystick and Gamepad Tester from AlphaOmega Software.  AlphaOmega produce a number of simple but ingenious apps which help you with your Mac, including an app which cuts out that annoying ‘chime’ when the computer opens (my car doesn’t sing at me when I turn the ignition, my hi-fi stays silent until I put in a CD, my TV remains mute until I select a channel – why on earth do computer manufacturers think we want to hear the machine start up!  One of life’s unexplained mysteries . . .), but also some apps which can have a value in computer music.  I may well have blogged about some others elsewhere.

The purpose of Joystick and Gamepad Tester is to tell you what controls your USB device has, and if they are devices like joysticks, what are the minimum and maximum readings you can get from them: 0 – 127, 127 – 255, etc.

I recently bought a game controller like this from a charity shop:

Logitech Buzz

It looked as if it was originally part of a quiz game, and had a USB connector, so it looked as if it would be easy to use with the computer.

I took it home, plugged it in and started up Joystick and Gamepad Tester.

JAGT 1

The instructions say to press all the buttons and move joysticks and other controls so they’re recognised. but when I clicked ‘OK’ on the screen above, I saw this:

JAGT 2

I found out first of all what the device was – a ‘Logitech Buzz Controller V1’ – and was able to select it from the drop down list.  Note by the way that all the normal USB-connected devices are also listed: in my case, there’s the laptop keyboard, the infrared receiver on the front and the trackpad.

The Apple IR Remote – listed in the screenshot above as ‘IR Receiver’ – isn’t exactly a game controller, and isn’t exactly an HID device like the others discussed here, but it’s worth a brief digression as its uses are very much the same.

As far as  Joystick and Gamepad Tester is concerned, nothing was listed when I selected ‘IR Receiver’ or registered when I pressed buttons on any of my Apple remotes – only when I selected one of the two entries ‘IOSPIRIT IR Receiver Emulation’.  I don’t know why there are two entries, but they’re identical and are the result of installing either the app Remote Buddy, or its free driver Candelair – or very probably both – as I’ve been working on using Apple Remotes recently (see blogposts, starting here).

A useful feature of  Joystick and Gamepad Tester in this respect was that it showed the remote’s individual ID No. in the ‘Now’ column.  (The ID numbers in the ‘Min’ and ‘Max’ columns are irrelevant, as they will just show the highest and lowest Remote ID numbers used in the past).  Just picking up a remote and pressing a button will change the now column to verify the number.

When I selected ‘Logitech Buzz Controller V1’, all the controls were already listed:

JAGT 3

There are 5 buttons on each of the controls, and the list suggests that they are unique – that’s quite a decent number of buttons for a game controller, so that could be handy in some situations.  Buttons usually show up with a minimum and maximum of ‘0’, so it was quite interesting see that 4 of them with a different reading in ‘Max’: perhaps these were the big red buttons, one on each handset?

Actually, there weren’t: as you go round the buttons pressing them, you can see exactly which is which – the value appears in the ‘Now’ column: ‘1’ for pressed, ‘0’ for not pressed, which is typical for buttons, so by the time you’ve finished, they all have ‘0’ in the ‘Min’ column and ‘1’ in the ‘Max’ column.  If you’re intending to modify the controller you’re testing by taking it out of its case and fixing new buttons to it, this is very useful because you can make a note at this point of which one is which.

Better still, if you click the ‘Save’ button – indicated by the arrow on the screenshot above – you can save the list as a text file, print it out and make your notes on that.

First you’re given the usual ‘Save’ options:

JAGT 4

Then  Joystick and Gamepad Tester confirms that the text file has been saved and it’s safe to quit or begin testing another device.

JAGT 5

I was impatient and clicked ‘Save’ before testing all the buttons, so the text file shows an incomplete test – I haven’t verified yet that each of the buttons gives a maximum ‘1’ when pressed and goes back to a minimum ‘0’ when released.

JAGT 6

I was intrigued by the two entries at the bottom for ‘X-Axis’ and ‘Y-Axis’.  I studied the device carefully, and could find no control on it which resembled a joystick, which is what an entry like this would be for: data from these sources wouldn’t just be a ‘0’ or ‘1’, but a number moving from perhaps as low as -255 to +255.  I’m assuming this indicated that the chip used in the device is capable of supporting a joystick, but this hasn’t been implemented.  Perhaps, if one knew how, one could hack the PCB which controls the buttons and add this capability.

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There are two things worth mentioning about HID devices at this point.  The first is that, provided you leave the USB output leads intact, you can remove the circuit board from the original case, solder your own buttons and potentiometers to it and it will still be recognised as the same device by the computer.  This was the theory tested by the Cybersynth, which is basically a Theresynth, as described above, with the PCB removed from the Rumble Pad and put into a completely different case.  It doesn’t look like it any more, but the computer still thinks it’s a game controller.

Cybersynthsm

In fact, you can also do this with an old computer keyboard.  It’s possible to remove the PCB from these, work out which connections make which letters and wire these connections to your own buttons or switches.  I did this with the board from inside an old Apple keyboard (as described here):

Blueberry keyboardsm

It was very cheap, having been scrapped as being broken, but what was wrong with it was nothing to do with the electronics.  I took the board out, rewired it, and use it for controlling a looping program.

MIDI CPU insidesm

You may be able to tell from this picture – although the scale isn’t particularly evident – that the PCB inside this particular brand of keyboard is ridiculously large.  You could undoubtedly find a make with a much smaller board which would be more practical.

As it happens, I’m using this particular board for an application which requires letters as an input, and no remapping – i.e. ‘A’ is ‘A’, ‘B’ is ‘B’ and so on.  However, since the keyboard is an HID device, using one of the programs above, you could change the functions of the buttons and have a very large number of different control buttons available: the equivalent of 26 letters, 10 numbers, numerous punctuation keys; and programs will normally distinguish between lower and upper case letters, increasing the total number of controls even further.

The second thing to mention is that there are many PCBs on the market with circuitry on them to output HID standard signals, and allowing you to attach your own combinations of buttons, switches, knobs and joysticks.  People who make their own arcade games like them, so this is where you’re likely to come across them (on sites like this, for example).

Some of these are relatively inexpensive.  I got this one, which can encode 12 buttons and 2 joysticks for £8.00, complete with connecting leads for the buttons, joysticks and USB:

Zero Delay Encoder Board Rev2 -2

You have a free choice of what kind of buttons to attach, and using a board like this is easier than extracting and rewiring an existing game controller board

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As for other types of controller: there are many.  This one by Nyko for Playstation – which I have in the collection, but haven’t worked on yet – combines the traditional game controller with a QWERTY keyboard:

Nyko IMG_1668

This one, the Airpad, is interesting because it contains a tilt mechanism which enables control by tipping the device up:

Airpad IMG_1667

You may notice something odd about the above two controllers – the funny connectors on the end.  Your computer probably doesn’t have sockets that shape.  This is no problem, though, as Playstation to USB adapters are easy to come by and not expensive.  This one cost less than £2:

PS Adapter IMG_1669

It’s also possible to find extenders and hubs for Playstation devices, and these don’t usually cost much second-hand on eBay:

Extension IMG_1255

Hub IMG_1561

Using PS3 (wireless) controllers is also perfectly possible.  There are drivers for Windows; later versions of Mac OS (from 10.6 upwards, I believe: see here for further details) have drivers built in, using Bluetooth.  Earlier versions of the Mac OS can work with a driver from Tattiebogle.

USB adapters also exist for XBox controllers, although replacing the proprietory connector with a USB plug doesn’t seem difficult,  according to this illustrated article.

[Edit: unfortunately, both the sites I used for this information are unavailable now.  I’ve left the link in case that site’s unavailability is temporary, and I have an image from the other one:

xboxcablemodpaintThis implies that the Xbox cables have wires using the standard USB colour-coding, so if the wire attached to your USB plug uses these standard colours, they can simply be attached like-for-like].

Once again, Tattiebogle provides a driver for wireless XBox controllers – although you’ll also need one of these wireless receivers:

wireless receiver2

Third-party receivers can cost as little as £5.

At the time of writing, the most advanced consumer-oriented controllers are the Nintendo wii and Microsoft’s Kinect.  The wiimote controller is a hand-held device which uses accelerometers and infrared to detect position and motion in addition to control by button-presses; Kinect uses infrared, cameras and microphone to detect spoken commands as well as hand and body positions from a distance.  I’ll be looking at musical uses of these two systems in the next post in this series.

07
Oct
13

Fun with the Apple IR Remote, Part 1: Making it work

This article, by and large, is for Mac owners, as it describes the Apple infra-red (IR) remote control system that’s been used on and off in Apple machines for about 7 or 8 years.  There is an article here which describes the remote being used on a Windows PC, and here on a Mac running Windows, but I imagine these are not common usages for this system.

In fact, I don’t believe the Apple IR system is well known at all amongst Mac users, and I hope this study will show that it can be more useful to music makers than was previously thought.

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From about 2005, Apple began adding an infra-red remote capability to their machines, which came with an attractive little remote control like this:

Remote IMG_1519

It’s not clear from the picture, but if you haven’t seen one, it’s quite tiny – about 8cm by 3cm.  I’ll be returning to that point in Part 2.

The IR system began with the iMac G5 and quickly spread to the white Macbook, Macbook Pro and Mac Mini.  A slightly larger silver aluminium version of the remote came out in 2009, but also in that year Macbooks stopped being made with IR capability.  It remained as an option on the Macbook Pro, but the remote itself wasn’t being bundled with the laptop.

This is the silver remote.  Note that the ‘Play’ button has been moved from inside the ‘+’, ‘-‘, ‘Left’ and ‘Right’ buttons, and placed separately, to the right of the ‘Menu’ button.

Aluminium remote2 MC377

At the time of writing, the Mac Pro and Mac Mini seem to have built-in IR capability.  It’s difficult to keep track of what does what, however, as newer models of computer seem to be dropping this feature and users are being encouraged to use an iPhone app which does a similar job; but if it has one of these on the front:

IR Sensor IMG_1521

then it’s got IR built in.  The one area where the control seems to have remained popular is with the Apple TV/Home Theatre users.  There was an application called Front Row, which used the remote to control films and music, but I don’t believe this has been in use since OS 10.7.

All of this is a shame, as the ability to control your computer wirelessly can often come in handy, and several companies produce excellent software which greatly expands the ability of the Apple remote to control pretty well any application in any way you want.

Of course, if you have a Mac, then you very likely have the luxury of Bluetooth as well, and I have blogged, or will be blogging, about various uses of Bluetooth.  However, it could be that your Bluetooth system is fully occupied with, say, your wii controller, and this extra way of passing information to your computer becomes a vital necessity.

Although most of the following is based on my experience with my MacBook, which has IR built in, I’ll be speaking about things one might do to add IR capability to a non-IR Mac.

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First of all, then, the controller and getting it to work:

There are three things to do to make sure your IR remote is potentially going to work.  The first is to ensure that the battery is OK; the second is to confirm that the infra-red LED is lighting up; and the third is to make sure the computer’s IR capability is turned on.

The remotes are powered by a CR2032 coin battery.  Apple designers, as we know, live in a world where bent paperclips are always to hand, so with the white remote – like the method of ejecting stuck CDs – there’s an indentation in the bottom of the case which can be poked with a bent paperclip to eject the battery tray.  In this case it isn’t inside a small hole, so a pen, pencil, or a 3.5mm headphone plug will also work perfectly well.

As illustrated, the silver remote has a different method: a battery compartment which is opened by twisting a small coin in it.

Battery change2

As for checking that the remote is functioning, the essential problem with this is that the light it gives off is infra-red, and therefore you can’t actually see it.

Fortunately, though, cameras can!  So if you have a laptop with a camera at the top here:

Camera IMG_1523

all you have to do it open something like iChat, go to Video > Video Preview and film yourself pointing the remote at the camera and pressing buttons.  If you can see a light like this:

Battery test

then the unit is working.

Finally, you just have to make sure the IR capability isn’t turned off.  Do this by opening System Preferences > Security, and look for this:

Security preferences2

Make sure the box isn’t checked and it says ‘The computer will work with any available remote’.

While on this subject, it’s worth noting that this might not be the situation you want.  If you’re in an environment where there are several remotes in use, you might want  your machine to respond only to yours.  Under these circumstances, the ability to ‘pair’ your remote and computer might be very useful.  Clicking this button:

Pair3

will enable you to do that (provided you’re logged in as an Administrator).

When you click it, it tells you how to do the pairing:

Pair2

Rather like a wii controller, you point the remote at the computer (but in this case it must be from just 3 or 4 inches away) and press the ‘Menu’ and ‘Next’ (‘Right’) button at the same time.  After a few moments (maybe 5 seconds), the following large icon will appear on the screen, with the ‘link’ sign flashing:

Pair icon IMG_1523

The remote and the computer are now paired; the ‘Pair’ button changes to an ‘Unpair’ button, and the text now says ‘This computer will work with only the paired remote’.

The process of unpairing them is simply a case of clicking that button:

Unpair2

Using the remote itself, you can unpair it by pressing ‘Menu and ‘Left’ at the same time, for about 5 seconds.

According to Apple, the remote works up to 9 meters (30 feet) from the receiver.  Unlike Bluetooth, of course, we’re talking about light here, so there can’t be anything in between the remote and the receiver that would block the signal – although you might be lucky and able to bounce the signal off a wall on on its way to the receiver.

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So, now the remote is working, what can you do?

The answer is, not a lot.  You can use Front Row to watch films or listen to music, unless you have a modern operating system, 10.7 or later; you can remotely control iTunes, or you can make your computer go to sleep and wake up.  Not very practical for making music, which is, after all, what this blog is about.

[Edit: since writing the above, I’ve installed OS 10.6 and a newer version of the program VLC, from Videolan, an excellent free audio, but predominantly video, file player.  Some of VLC’s functions can be controlled with the Apple Remote, which is handy.  I don’t know if this can be done with earlier versions of Mac OS].

So, an important part of making the remote work would be to find some suitable software to interpret the input.

The first thing I looked into when I got my remote out of the cupboard and got it working was whether it would work with PureData (Pd).  Many types of HID (Human Interface Device) will act as musical instruments or effects devices – as I have described in the blog before – and so can the Apple IR Remote, although only to a limited extent.

I used a generic ‘HID Tester’ patch which I had created for investigating different devices, and determined first of all that the IR system was recognised by Pd – in this instance as Device 0:

Pd device no

I activated Device 0 and pressed all the buttons in turn, but this is all I got:

print desktop2

So unfortunately Pd was only able to recognise two of the buttons on the IR Remote, ‘+’ and ‘-‘.

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This was of limited value, so I needed to see if there was any software which could expand the usefulness of the device.

Luckily, there was.  There are several programs, in fact, which can greatly extend the range of control  the Remote can give you.

Andreas Hegenberg’s BetterTouch Tool (BTT) has a section for the Apple Remote, although is generally more aimed at the Magic Mouse and trackpad

bettertouch2

Nowadays, in fact, Andreas seems to be concentrating on the amazing Leap Motion Controller, which is going to deserve its own blog page one of these days.

I wasn’t able to test out the BetterTouch Tool: it’s free, so there’d be no problem for you downloading it (from here, for example) and trying it out, but only supports OS 10.7.  There might be a legacy version still available for 10.6, but I couldn’t find one for 10.5, which I’m still using.

I did find a screencap, though, which shows that button presses are known as ‘Gestures’.  This is an example of the window in which button presses are assigned different actions:

BTT Gesture setting

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Mira is a dedicated Apple Remote app which, when installed, is controlled from System Preferences.  The opening view shows the remote buttons in the centre: you click on each button to assign a function to it, which may be a keystroke, system action, or instruction open a program (including AppleScripts).

mira windows

Mira supports short presses and long presses, effectively doubling the number of actions available from the 6 buttons, and provides a number of combinations of short press/long press combinations.  A comprehensive Help menu is available by clicking the ‘?’ button in the bottom right-hand corner of the Mira window.

Duo Press_Help

Mira is available from Twisted Melon in versions for OS 10.4+ and 10.5+.  Also available, for the deprived Mac with no IR receiver, they offer the Manta TR1 plug-in USB IR receiver.  At the time of writing Mira costs $15.95 (Canadian) for single licence and $29.99 for 3 licences; the Manta TR1 costs $19.99; and a bundle of 1 Mira licence and a Manta costs $29.99.

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Remote Buddy looked particularly promising as it also offered control of wide array of remotes, not just the Apple remote, but other makes from the likes of Griffin and Sony, iPhone and iPod Touch, and even Nintendo wiimotes.  OS 10.4.6 and above are supported.

Remote Buddy also installed its driver, Candelair (also available as a free stand-alone).

Configuring the remote’s buttons consists of specifying an application – although ‘Default’ and ‘Virtual Remote’ options are available – and defining a group of actions called ‘behaviours’.

Picture 2_2

There are appropriate suggestions for each application, and you can create your own Custom actions.  Like Mira, Remote Buddy supports short and long button presses and allows the same kinds of action choices; Help is available from the Remote Buddy menu.  It costs €19.99.

As a matter of fact, once I had installed Remote Buddy/Candelair, the following entries showed up in PureData:

Pd Remote Buddy_Candelair Devices2

Opening these device numbers, I was able to see two more actions displayed:

Pd long press l & r2

However, I wasn’t able to use these with the [Route] object, as one normally would.

Even if you don’t use Remote Buddy, I’d recommend installing Candelair, as I’ve encountered a number of instances like this where the presence of this alternative driver allows you to do things that can’t be done otherwise.  It can be controlled – even uninstalled – in System Preferences:

Candelair Screens

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Undoubtedly, the be-all-and-end-all of infrared applications is iRed.  Designed to work with the iTrans infrared module – which transmits as well as receives  – this system can, in a nutshell, allow you to control your computer with any infrared control and allow your computer to control any device with an infrared receiver.

Possibly slightly extravagant for present purposes – and it doesn’t work with the standard Apple IR receiver, of course (which doesn’t transmit).  However, iRed Lite is much more the sort of thing I’m considering here.

In fact, for several reasons, this is the one I chose to use, partly because it’s free, partly because I liked the flexible onscreen display window, partly because it recognises short presses, long presses and double presses.

When opened, all that appears is an icon in the menu bar.  Clicking on this icon brings up a choice of actions, including opening the Onscreen Display or the Editor window.  This view of the Editor windows shows some of the important features:

Edit window

1.  This panel replicates the Onscreen Display.  The buttons are laid out here in the same format as the buttons on the remote.  The ‘extra’ button at the end of each row is for the ‘double-click’ action.

2.  This section, when the ‘Button’ tab is selected, allows for changing the style of the buttons.

3.  In this section the action performed by the button can be changed.

4.  This drop-down menu, as the name suggests, allows the settings for different Layers to be displayed.  A Layer is a collection of actions, usually applying to the same application.  When a Layer is active, the actions described in that layer are the ones which will be performed when the remote buttons are pressed.

5.  This drop-down menu gives access to more functions, such as remove selected button, create or remove a Layer and open the Character Palette for access to special characters and symbols.

6.  Clicking this arrow reveals or hides the sections on the right-hand side of  the picture in which more complex actions can be specified.

7.  Clicking on the ‘Add Action’ button allows actions to be specified which replicate keystrokes or mouse movements; a third possibility is to run an AppleScript.

8.  The special action is chosen in this area.  The picture shows a simple AppleScript to initiate an iTunes function.

Actions can be dragged and dropped onto the buttons in the panel on the left and different patterns of buttons can be created for ease of understanding or to match modified remotes.

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Modified remotes is the subject of Part 2 of this series of posts, but before we leave the topic of software, I must just mention a small command-line app which runs from the Terminal.  I haven’t yet worked out if this is potentially useful or not yet, but it’s called iremoted and ‘listens for button-press events and prints the identifier (the HID element cookie, to be precise) of the button in question’.

A description of the program can be found here, together with the source code in a file called iremoted.c.  Its GitHub entry is here.  I compiled it from the Terminal by typing the recommended instruction ‘gcc -o iremoted iremoted.c -framework IOKit -framework Carbon’.

When I ran it, sure enough it showed me the HID element of the code sent by each button press, like this:iremoted Terminal window2

It’s interesting that ‘+’ and ‘-‘ were the only two buttons that showed an entry when pressed before another entry when released.  Whether this has anything to do with the fact that they were the only two buttons to show up in PureData, I don’t know.

The above isn’t the only information passed via the infra-red link when a button is pressed.  I’ve read numerous articles on the subject which, frankly, I don’t understand – they either don’t say the same thing, or they say the same thing in a different way . . . suffice it to say that 4 different pieces of information are transmitted each time a button is pressed, according to the NEC Infrared Transmission protocol, which Apple remotes use (in a slightly non-standard way): the first two are purely Apple’s own ID, the third is the instruction code, as above, and the fourth is the remote’s individual ID.

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The individual remote ID is the final thing I want to deal with in this post – which I ought to do, as I glossed over it rather surreptitiously when talking about ‘pairing’ earlier on.

When you pair a remote with your computer, you’re not pairing just any remote in the vicinity: you’re pairing a particular remote; and the way the computer knows which particular remote is being paired is because of its individual ID, which is a number from 0 to 255.  This isn’t fixed: it can be changed, although not to a number of your choice.

The advantage of pairing a remote is that you can – as  in my earlier example – ensure, in an environment in which several remotes might be in use, that your computer responds only to your remote.  If by some chance you find yourself in a situation in which there are two remotes with the same number, you can change the number and re-pair it.  To change the number, all you do is press ‘Menu’ and ‘Play’ (the centre button) at the same time, and the number will increment.

I have read that the remote will attempt to pair when you do this, so if you don’t want to pair at the same time, do this outside the distance from the computer (3 or 4 inches) which is required for pairing to work.

So, pairing can be useful.  But what might be even more useful is not to pair a remote with your computer, but to allow the computer to recognise individual remotes by their IDs and have them do different things.  Programs like Remote Buddy do this, as the following screen shots show:

Multiple Remotes

Checking the box ‘Enable support for multiple remotes’ – indicated by the arrow at the top – brings up the list beneath.

In the right-hand column, remotes are distinguished by their ID number, not paired, but associated with different ‘behaviour’ groups.

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In the iRed Lite Editor window, clicking on the ‘Layer’ tab brings up a number of parameters that can be altered, one of which is the ID of the remote which will control this layer.  The actions described will not be performed by another remote with a different ID.

iRed Layer window2

This raises the possibility of using a number of separate remotes for entirely separate purposes, using modified remotes with multiple ‘personalities’, or teaching a universal remote with a learning capability to mimic remotes with different IDs.  This article: http://funwithcomputers.wordpress.com/2008/03/01/using-the-harmony-880-remote-with-your-macs-built-in-ir-port/ describes a project to teach a Logitech Harmony 880 to imitate 8 Apple remotes via Remote Buddy.  In this way 48 different buttons were created (could have been 96, but long presses were not configured) and all manner of things could be controlled in a home theatre set-up.

At some point, you might want to check the ID Number of your remote.  If you’ve only got one, chances are its number will pop up everywhere.  If you have more than one, someone else uses one in the vicinity of your computer, or you haven’t really used it before, here are two ways to find out what it is.

The first thing to say is that isn’t always quite as easy as it might be, as only ID number changes seem to be registered.  If you have more than one remote, it’s less of a problem – every time you use a different remote there’s a number change; if you have only remote, the following needs to be done the first time you use your remote after booting up the computer:

Open iRedLite and select ‘Preferences’ from its drop-down menu, and then ‘Apple Remote IDs’.  It will probably show ‘0’ as the current ID number.  Press a button on your remote, and it will display the remote’s ID number, as below.  If you have more than one remote, you can check the numbers here at any time, as the change from one ID number to another will be registered (although once I was fairly sure I wouldn’t be incrementing the IDs any more I wrote the numbers on the back of each remote!)

Apple Remote ID No window2

Another useful program you could use for this purpose is Joystick and Gamepad Tester.  I’ve blogged about this at greater length elsewhere, but since the Apple infrared receiver is part of the USB system, it will be picked up by this program, which is designed to identify buttons and other controls on USB devices (such as joysticks and gamepads).
In my experience, this only worked after I’d installed Candelair, as recommended above.
I open Joystick and Gamepad Tester and click ‘Ok’:
JAGT 1
I can then choose from a drop-down list.  Instead of choosing ‘IR Receiver’, which normally shows nothing, I choose ‘IOSPIRIT IR Receiver Emulation’:
JAGT IOSPIRIT

A list of buttons and functions appears, the last being the Remote ID number.  Pressing a button on the remote shows the current ID number in the ‘Now’ column.  Any button will do, as the device’s ID number is transmitted as part of every message.  Don’t take any notice of the ‘Min’ and ‘Max’ columns, as they just show other device ID numbers that may have been used before.

JAGT ID No

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Some of the above could only legitimately be described as ‘fun’ by those of us with a rather esoteric definition of the word.  In Part 2 I’ll progress closer to using the IR remote for modification and music-making purposes.

22
Aug
12

Stylophones 3 – The Stylophone 350S, Part 1

A series on the Stylophone can only reach a climax with the mighty 350S!

The question of why the original Stylophone sold in its millions and became a world-wide success story, and the 350S didn’t, has long been debated.

According to http://stylophonica.com (‘The official home of the Stylophone’), it was ‘too costly, and lost the key uniqueness of the Stylophone itself, which was its small size and mass-market appeal’ – but it certainly wasn’t through of a lack of features.

You may be familiar with the Stylophone, but not the 350S: if so, then to start with, a run-down of its capabilities is required:

First of all, it’s certainly true to say that it’s much larger than the regular Stylophone – which is, after all, about the size of an inch-and-a-half thick postcard.  Here’s my 350S together with the regular-sized ‘New Sound’ Stylophone with which it shares many of its design cues:

350s + New Sound IMG_1050

The 350S is a souped-up Stylophone in every way: instead of the Stylophone’s 20 notes – an octave and a half – the 350S has 44.  That’s three and a half octaves, and you can see in the picture the difference in length between the two keyboards.

Not only that, the 350S has eight voices, as opposed to one (or even the S1’s three), and some of these are themselves in different octaves.

The voices are designated ‘woodwind’, ‘brass’ and ‘strings’.  In these days of sample-based synths, none of these sound terribly much like what they say they are, but they have the general qualities of these instruments – and, despite what you may read, one or two of them are quite like the distinctive tone of the regular Stylophone that we all know and love!

These voices are:

four ‘Woodwind’ voices pitched at four different octaves, and described (like organ stops) as 16′, 8′, 4′ and 2′;

two ‘Brass’ voices at 16′ and 8′; and

two ‘Strings’ voices at 4′ and 2′.

Because these voices are pitched at different octaves, from 2′ to 16′, in all no less than six and half octaves are available from the bottom of the keyboard to the top.  This is almost as large as a ‘professional’ 88-note synthesizer keyboard.  Up to two of the voices can be combined at any time, one each of the four octaves.

As well as this wide range of voices, the 350S has a variety of built-in effects.  Like the regular Stylophone, one of these is Vibrato – and two speeds are available, rather than one.

There is also a two-speed ‘Decay’ facility: as well as the usual Stylophone ability to hold a note as long as the stylus is in contact with the keyboard, when the Long or Short (actually, ‘short’ or ‘very short’) Decay button is pressed, the note will fade out while the stylus is still in contact.  According to the nicely-produced, LP-sized User’s Guide that comes with it, this enables the player to obtain ‘a percussive effect rather like  piano.’

350s rocker switches IMG_1053 sm

However, as can be seen from the above picture, this is only the beginning of the 350S’s abilities.

The fast or slow ‘Reiteration’ button (second from the left) can be used to imitate the sound of a banjo or mandolin, and the 350S even has a second stylus which is used to produce these effects.

Normally, whichever stylus is being used, the ‘regular’ or ‘reiteration’, it’s held in the right hand; but it’s possible to play two notes at once in reiteration mode by using the reiteration stylus with the right hand, and playing lower notes with the regular stylus in the left hand.  It doesn’t work the other way round, and it doesn’t work in ‘normal’ mode, i.e. without either the fast or slow reiteration switch pressed.

The white tuning control can also be seen in the above picture – handily placed on the front of the instrument, unlike its counterpart in the regular Stylophone, which is always hidden underneath.

The most unusual effect, though, has got to be this:

350s Photo control IMG_1052

Above the volume control is the 350S’s secret weapon – the ‘Photo Control’.  This device, operated with the player’s left hand while the stylus is wielded in the right, can be set to control the volume, amount of vibrato or low-pass filter cut-off point – acting as a ‘waa waa’.

On the side of the 350S, next to the Photo Control, are three 1/4″ mono jack sockets.:

350s sockets IMG_1051

While one of these is ‘sound in’ and another ‘sound out’, the middle one is a socket for a foot pedal that replaces the Photo Control – either because the player would prefer to control volume, vibrato or waa with their foot, or because the ambient light level is too low for the Photo Control to be effective.  A 50k – 100k potentiometer does the job, according to the User Guide.

My experience of light-dependent controls like this – and I’ve made a number of them – is that they are really only fully effective when quite a bright light is shining on them, which is not always the situation when you sit down to play.

Unsurprisingly, this magnificent machine requires a fair amount of juice, so it’s powered by not one, but two weighty PP9 batteries, connected in series to provide 18v of power to the 350S.  [Edit: but see notes below about powering the 350S].  The batteries are housed underneath the rear of the instrument:

350s back IMG_1056

The battery covers look as if they’re held in place by screws, but these aren’t really screws: they click into place when pushed, and just require a slight turn with a screwdriver or a thin object to loosen them.  (The User Guide suggests a coin, but in my experience modern coins are too thick to perform this function.  Maybe a 5p would do it).

This is the User Guide that came with the 350S:

p1

350sBooklet

Reliable information on when the 350S first came on the market, how many were sold, etc. seems hard to come by.  http://stylophonica.com says: ‘No more than a few thousand 350S’s were ever sold’; http://stylophone350s.com/ says ‘Dubreq, the manufacturer of the original Stylophone created and produced the Stylophone 350S beginning in 1971 . . . fewer than 3000 were ever produced’ and quotes a Ben Jarvis (son of Stylophone inventor Brian Jarvis and re-founder of Dübreq in 2003) estimate that only 200-300 working units are probably still available worldwide.

I’d be surprised if the numbers were quite this low, but they’re certainly not common, and those that appear on eBay in the UK frequently command in excess of £100, rarely less than £70. Stylophone350S.com in the States have access to a recently discovered cache of mint condition boxed examples, which are now on sale.  Their website tells the story of this amazing find.  [Edit: this site is now defunct, unfortunately.  I don’t know what happened to the mint condition 350S’s that were for sale there].

The back of the 350S is removed by undoing 4 large screws in the corners and two very small screws under the front, and reveals two printed circuit boards: a thin, narrow one at the front containing the keyboard and the resistor chain – not discrete resistors, but what I’ve previously called ‘resistor modules’, since I can’t remember what the proper name for them is – and a large, rectangular one with everything else on it, including potentiometers, sockets and switches:

Just opened IMG_1068

The circuit boards themselves come away quite easily: there are 4 screws, clearly visible in the above photograph, which hold the keyboard in place, and 6 similar ones for the larger board.  The volume control knob doesn’t need to be taken off – it fits through the hole surrounding it – but the plastic nuts on the three sockets need to be removed.

This is what the other sides of the boards look like:

Component side IMG_1070

Here we see the larger items across the middle of the board, from left to right: the three sockets, the volume control, the eight voice and effect switches, the pitch control and the on/off switch.  If I was an electronics expert, I could tell you what the rest of the components do; but I can’t.  I can only surmise that the round inductor next to the left-hand switch is to do with the waa circuit; the LDR (light-dependent resistor) to the left of that is the ‘Photo Control’.

LDR & Ind New IMG_1144

The black ‘hood’ that partly surrounds the LDR was slightly damaged when I came to look at it, and it’s quite possible that I did this myself when I opened the case.  It was easily repairable with a spot of superglue, but watch out for this if you’re looking inside yours.

The ferrite core inductor is a Mullard FX2236.  In this close-up you can see that mine looks a bit broken.  I don’t know enough about these things to know if this means it isn’t working properly, but, while by no means common, they can be found – perhaps more easily in the UK than elsewhere – so I shall certainly consider replacing it.

According to the experts at www.stylophone.com, under the heading ‘VITAL INFORMATION WHEN BUYING A 350S… PLEASE READ CAREFULLY!’, one of the components you can see here – which they describe as the ‘Amp-ic’ – is highly prone to failure.

The related website, the Stylophone Information Centre at www.stylophone.fsnet.co.uk says: ‘The circuit board carries an IC which controls sound output, and this component (long since obsolete) is the single- most likely cause of the 350S to break down. If this happens . . . the unit will only be heard if played through a separate amplifier, if at all.’

The symptoms to look out for are: ‘when the stylus is applied to the keyboard, only a very faint sound is heard (if even audible at all), which fades away rapidly . . . Even with the volume control turned up to max, the sound will still be very low – then quickly fall away. The user will then be left with a ‘dead’ 350S.’

The chip in question is this one – the black one with six legs in the middle of the picture:

MFC6070 New IMG_1145

It’s a Motorola MFC 6070, 1-watt power amplifier  – ‘designed primarily for low-cost audio amplifiers in phonograph, TV and radio applications’, according to the datasheet.

If you don’t know what a phonograph is, ask your grandad, he’ll remember them!  The use of this antiquated vocabulary confirms what is said above.  If you find the datasheet for this chip, it says ‘Device discontinued – consult factory’; if you try to buy one on the Net, you’ll mostly find specialist sites, dedicated to sourcing obsolete parts.

As a matter of fact, you can, at the time of writing, get one on eBay for about £20, but you aren’t going to want to do that: the problem doesn’t arise, apparently, just because 350S’s are now all old – it even used to happen to quite new ones.

Stylophone.com told me that ‘the original chips as fitted . . . were working very close to their breakdown point voltage-wise. Although theoretically all the chips supplied to them should have worked, Dübreq actually had to batch-test the chips to find those with an acceptable working voltage range, especially the maximum voltage’ (which is meant to be 20v). ‘We’ve seen some of these chips.’ they said, ‘ running extremely hot (basically too hot to touch) by simply switching the instrument on, before even playing a note.’

That’s not to say the MFC6070 was a particularly unusual part at the time – they were used all over the place, and even the venerable VCS3 synthesiser used one as a driver for its spring reverb circuit.  However, as the site offering VCS3 spares, http://www.synthi.com, says: ‘The Achilles heel of the VCS3/Synthi AKS are the now obsolete and ultra rare semiconductors that it uses’ . . .

This made me think twice about powering the 350S with a mains-powered adapter: the increased risk of overdoing the voltage and blowing the chip might not be worth it.  Dübreq themselves did apparently produce some 350S’s with an ‘adaptor socket factory-fitted’, but ‘this led to many of them blowing the chip.’

I’m not quite as worried as I was, however, as stylophone.com are now marketing a new module, the ‘Stylophone ACM’, which can be retro-fitted to an ailing 350S – or even to a working one, as a precautionary measure – to get round this problem altogether.

The circuitry inside this unit is not operating close to its limits, and makes it much safer to run the 350S from an 18v adapter.  (And if you buy a reconditioned 350S from stylophone.com, it will already have one of these in it).

[Edit: see comments from Christian Oliver Windler below relating to powering the 350S.  He concludes from his tests that the 350S could – and should – be powered at less than 18v, and preferably less than 15v.  Some of the above problems and their expensive solutions can thus be avoided.

As with the original Stylophone, by the way, there appear to have been various upgrades during the course of production, and it’s interesting to note that some of the components inside Christian’s 350S differ from those in mine].

As a matter of fact, this is not the only ‘obsolete’ component in the 350S.  Although the resistors, capacitors and transistors that fill the circuit board are not commonly used in new designs nowadays, they’re still readily obtainable; the round silver integrated circuit over on the right-hand side, just above the tuning control, isn’t.

AY15051 New IMG_1142

It’s a General Instruments AY-1-5051, and what it does is frequency division (presumably for the 350S’s different octaves) – the kind of thing modern CMOS 4000-series chips do with the greatest of ease.  There’s a description on this website: http://www.divdev.fsnet.co.uk/repair2a.htm of how one might make such a replacement (using the example of a 1960s Elka electronic organ).  All I can say it, it looks feasible in theory, but not something I’d want  to be faced with in practice – let’s hope this isn’t a part which is going to fail!

Returning to my 350s, it looked badly in need of a clean up.  There was a lot of dust inside it, and over the years the keyboard had got very dirty:

Corroded keyboard IMG_1072Dust and corrosion IMG_1076

The switches sounded OK – no crackling or intermittent operation, so I left those, and just cleaned the circuit board and keyboard.  The keyboard in particular needed attention from, in order, a soft brush, switch cleaner, WD40 and Brasso.   This seemed to do the trick, and it began to look shiny again.

I cleaned everything, including the switch rockers, the case and the tips of the styluses, and put it back together again.  It now looked much better, and sounded clearly and reliably on every note.

Outside after cleaning IMG_1091

In my next post in this series, I’ll take a longer look under the bonnet of the 350S and see what there is to see.

21
Jul
12

Stylophones 2 – Variations

As I said in my first post on the Stylophone, there have been a number of variations in Stylophone design over the years, so I thought I would illustrate some of these from the examples in my collection.

The earliest Stylophone – in the days before Rolf Harris adorned the box – looked like this:

Original Stylophone + box IMG_1035

This early variation is distinguished by the non-playable black sections of the keyboard.  There were three types, distinguishable only by the body colour – the black one illustrated was the ‘standard’, but there was also a white one, the ‘treble’, and also a ‘bass’.  I don’t know what colour it was: I’ve only ever seen it in pictures, and it looks like a reddish-brown to me, but I’m colour-blind, so an unreliable witness . . . I hope in time to get hold of one, and somebody will tell me if it is indeed brown!

Here is the booklet that you see pictured above:

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Read the Original Booklet.

The black sections of the original keyboard had been a feature of Brian Jarvis’s prototype – which you can read about here: http://www.stylophone.com/Prototype.html – but the next generation of Stylophones dispensed with them.

There were still three types – the black ‘standard’, the white ‘treble’ and the (presumed) brown ‘bass’, and they looked like this:

2nd generation IMG_1057

Note the identical case design to the original, but the keyboard is now completely silver.  (Ignore the switches on the sides of these instruments – they’re a speaker cut-out modification I made to them many years ago).

The circuits in all these early Stylophones were quite similar, although not identical.  The instrument was subject to constant development, and there are versions with all discrete components, including the resistors which determine the pitch of the notes, and versions with different types of resistor modules – rows of resistors in a single unit.

It’s easy to peer into the inside of the original and ‘2nd generation’ Stylophones: the back is designed to be easily removable, in order to change the battery, and the component side of the circuit board is visible.  This is the inside of an original version (the one with the black sections on the keyboard):

Original inside IMG_1060

As you can see, in the middle, just above the piece of foam rubber which keeps the battery in place, there is a row of resistors connected to the keyboard, which determine the pitch.  This arrangement continued with the 2nd generation Stylophones.  This is a view inside the black ‘standard’ version pictured above:

2nd gen black inside IMG_1058

(Ignore the large resistor at the back right-hand side – this is attached to the speaker cut-out mod).

At some time during the production of the 2nd generation Stylophone, resistor ‘modules’ came into use.  This picture of the white version pictured above, shows two orange-coloured blocks in place of the row of separate resistors:

2nd gen white inside IMG_1059

Other slight changes were made to the component layout, and the style of the switches in the bottom right-hand corner is different.  (Once again, ignore the non-original large resistor next to the speaker).

This would be a typical version of the circuit from this period:

Stylophone schematic 2

A slightly different one is illustrated here:

http://www.waitingforfriday.com/index.php/Reverse_Engineering_the_Stylophone.

Also at some point during production of the 2nd Generation Stylophone, there was a major change on the outside.  The shape and colours didn’t alter, but the guide to the notes, printed on the white background piece stuck around the keyboard and switches changed from showing notes (‘A’, ‘A#/Bb’, ‘B’, etc.) to numbers (‘1’, ‘1 1/2’, ‘2’, etc.):

Letters & Numbers IMG_1057

(These are the same two black and white Stylophones shown above).

This was the beginning of the famous Stylophone song-teaching method, which continues until this day.  Whereas the songs you learned from the original booklet were shown with notes, like this:

Original Booklet p7

songs were now shown with numbers, like this:

p8

Edit: However, there is a photograph of an object from the collection of the Museum of Design in Plastic at http://www.modip.ac.uk/artefact/aibdc–002025 which shows an original issue Stylophone (the one with the black sections on the keyboard) in its packaging: and one of the items included is an overlay for the keyboard surround.  First of all, this is white lettering on a black background, rather than black lettering on a white background; secondly, it uses numbers, not letters for the notes.

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The third distinctly different type of early Stylophone was the ‘New Sound’, which came out in around 1975.  The sound was ‘new’ because instead of the transistor in the original, the oscillator used a 555 integrated circuit.  Mine came in a box featuring Rolf Harris:

New Sound in box IMG_1048

This Stylophone featured, for the first time,a volume control, which can be seen on the left of the front panel, just above the on/off and vibrato switches.

The circuit for the ‘New Sound’ version looked like this:

555-based Stylophone circuit.LARGE

This view of the inside of the ‘New Sound’ shows the black, rectangular 555 chip just above the centre of the circuit board:

New sound inside IMG_1061

The Booklet that came with the ‘New Sound’ Stylophone was more extravagant than the original – although it was only printed in black and white, it was 16 pages long and the pages were about twice the size:

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Read the New Sound Booklet.

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Edit: Not part of my collection, but of interest nonetheless, is a variation made in Hong Kong and sold mostly in the United States.  These are described in detail at http://www.stylophone.ws/hk.html, but a correspondent, ageing60hippy,  has sent me some very nice photos of one that he has.

It can’t be stated for certain if these stylophones were copies as a number were manufactured under licence at this time, but they have several features which differ significantly from the versions being made in the UK.  Note the ® symbol after the Stylophone logo on the front grille, the socket for an external 9v power supply, and the small battery compartment on the back.

Imgp3462Imgp3436Imgp3443Imgp3449

Inside, the circuit board design is different and the construction quality perhaps not quite the equal of the originals, but not bad for this period:

Imgp3458Imgp3450

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All of these early series of Stylophones offer opportunities for modification and circuit-bending: the electronics aren’t complex, circuit diagrams are often available, and the components themselves are large and readily accessible.

I haven’t worked on these much, but my SoftPot Stylophone is a modified ‘2nd Generation’ treble version.  The ‘Hedgehog’ uses a Stylophone ‘New Sound’.

Production of the original Stylophones ceased in 1980 and the manufacturer, Dübreq, moved on to other things (‘Top Trumps’ playing cards!), but in 2006 the design was revived.

The new ‘Stylophone S1’ had different electronics inside, but a more or less identical case design.  Only by looking carefully can you see the tell-tale signs: the extra socket on the side – an ‘mp3’ input – a volume control on the right-hand side, and a three-way tone switch on the front, none of which is present on any of the 1960s and 1970s Stylophones:

Stylophone S1 2

Several colour variations – sometimes referred to as ‘Special editions’ were produced.  These were all-black (‘ebony’), silver and white:

4 S1s IMG_1044

Unlike the earlier Stylophones, the colour isn’t an indication of different sounds – as all S1’s have 3 tones, there was no longer any need to make three different types.  They’re all identical on the inside – although I did have the impression that a little more care was given to the assembly of the Special editions, compared to the standard version.

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In Asia an even more completely black version, the ‘Stylophone Studio’ was marketed:

StylophoneSBE_package_Full lge

They’re very uncommon in Europe and I’ve never seen one.

[Edit: I’ve finally acquired one!  Here are some pictures:

IMG_0607aIMG_0612IMG_0613

As you can see, it’s VERY black!  I like the contrasting white switches].

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This is the booklet that came with the Stylophone S1:

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Read the S1 Booklet.

The version that comes with the black ‘Stylophone Studio’ is mostly in Japanese (at least mine is, having been purchased from there; different languages may have been used if it was sold in other countries):

IMG_0609_10IMG_0611_12

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Another rare variation of the S1 is the so-called ‘Raconteurs Tour edition’ – a special version made to be sold as part of the merchandising connected with The Raconteurs,  a band formed by Jack White after the dissolution of the White Stripes.

Both the colour scheme of the instrument and the package design were unique, with a distinctive black and gold colouring:

Raconteur + box IMG_1036

In addition, the contents of the booklet were customised for the band:

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Read the Raconteurs Booklet.

According to a concert-goer (at http://cousinsvinyl.com/2008/dude-check-out-the-merch-raconteurs-and-black-lips-play-the-fillmore-detroit/): ‘I was very curious to see what a Stylophone was.  The box read “The Original Pocket Electronic Organ”.  My friend said, “Dude, you’re going to want to get one of these,” as he opened the box.  It was $40, but worth the money: it’s a working instrument with the Raconteurs logo on it.  The next day, it was worth $200 online.’  Mine was a lucky find on eBay, but these can be very expensive when you come across them, usually more than the original $40 price tag.

[Edit: True at the time of writing, but less so now!]

As an added attraction for those who bought the Stylophone at Raconteurs’ gigs, the band held a competition, inviting fans to submit Stylophone versions of their songs.  The competition was announced on the band’s website:

Raconteurs competition

 The video made by the winner, Zach Herrmann, can be seen on YouTube at http://www.youtube.com/watch?v=2eK17MqWIo0. [link now dead]

The circuitry of the S1 is very different from the earlier Stylophones, being based on a tiny digital chip which you can’t even see as it’s covered in a blob of protective wax.  It has a separate amplifier circuit board.  It also runs on 4.5v, not 9v, so instead of a PP3 battery it takes three AA batteries.  These are not inserted by removing the back of the instrument like the earlier ones, but are held in a battery compartment accessed from outside.  For this reason, the S1 is glued shut and getting to the inside of it for the purpose of modification (or troubleshooting) is not a simple matter.

The only picture of the inside of an S1 I seem to have to hand is this one, which has points marked on it for a ‘feedback’ bend: but it clearly shows the components which are visible on the main circuit board – i.e. not very many! – and the amp board in the background:

Inside stylophone sm

The chip which does all the work is under the black blob; the resistors are tiny surface-mounted (SMD) type.

For this reason, modifications and circuit-bending opportunities are a little more limited than with the early series of Stylophones.  Elsewhere in the blog are one or two examples of my efforts: The ‘Alien’ was my first modification project; the ‘Gemini’ uses two S1 boards in a single case.

And finally, a word about the smallest ever Stylophone, the Stylophone mini:

stylophone-mini

This one really is miniature!  Measuring a mere 8cm x 4.5cm, this is an official Dübreq/re:creation product, and is a perfect reproduction of the regular Stylophone.  Powered by 3 AAA batteries, it has a working stylus and the full complement of 20 notes.  The only thing it lacks is the Stylophone’s traditional Vibrato.

Here is a Stylophone mini with a regular Stylophone S1:

Mini Stylophone IMG_1042

Inside, there seems to be very little indeed!:

Stylophone mini IMG_1094

It looks as though the keyboard is connected to a small piezo element acting a sounder, with very little in between!  I didn’t take the circuit board out on this occasion to look, but I suspect, like the S1, the chip which operates the Stylophone mini is very small and surface-mounted on the other side.  It certainly looks as though modification and bending possibilities are limited.

That’s an overview of the mini and regular Stylophones; my next post on the topic will deal with the amazing machine often described as the Stylophone’s ‘big brother’, the 44-note, 8-voice Stylophone 350S:

Outside angle after cleaning IMG_1089

08
Jun
12

Bits & Pieces 4

I wasn’t expecting to add this post just yet, but I had a stroke of luck which has enabled me to complete the scheme for my mono mixing section which I started writing about when I described the Red Dragon the other day.

I bought a job lot of small SoundLab mixers off eBay which were said to be faulty returns.  I thought I might be able to salvage some parts from them, use bits of them in some way, or even repair them – but it turned out that several of them appeared to be in working order.

Two of them were straightforward 4 channel mono mixers – an updated version of the one I had used before, I presume – so these were immediately used for the left and right channel inputs to the mono mixer, as I described in the previous post.  Generally speaking, I wanted to have the lower tones to the left and higher tones to the right, so my ‘double bass’ stylophone was the first thing to be plugged into the left mixer; the treble stylophone and the SoftPot Stylophone in the right.

4 Mixerssm

More interestingly, the two other working units were the G105C version with ‘microphone effects’ – a delay circuit which I guessed was probably based on a PT2399.  I opened up one of the dead ones, and found that this was the case.

The circuitry was very different from the original SoundLab mixer I’d acquired – all surface-mount components; everything, pots and sockets included, firmly fixed to a single circuit board – and I’m not sufficiently skilled or equipped to be able to repair something like that.  Not only was it not functioning, it seemed to short out the power when the on switch was pressed.

I sawed out the part of the circuit with the PT2399 on it, which didn’t short the power when used by itself, but didn’t do anything to the input sound either.  This section is permanently in circuit when the mixer is operating, so maybe that was why the original unit didn’t work.  In any event, I decided to put the broken ones away for another day, and concentrate on the ones that worked.  The case would find a use later on.

First of all an echo unit is a really useful thing to have – and 2 echo units with 4 inputs is a bonus!

My initial arrangement with these is to have the outputs connected to the new Left and Right Mixers.  The left echo unit is used for instrument input and the output is divided: one half of the output going directly to the Left Mixer, the other half going to the right echo unit, and from there to the Right Mixer.  As the delay time and feedback (number or length of repeats) are separately adjustable on the two units, some interesting stereo effects are possible.

16
May
12

Bits & Pieces

I’ve called this post Bits & Pieces because it isn’t about electronic musical instruments, but a few modules I’ve recently made, not all of which are greatly interesting in themselves, but have a use in my set-up.  These are:

1. Extension speaker

2. Headphone Amp

3. Headphone/speaker select switch

These are not highly significant, but I’ve spent time making and using them, so I thought I might as well briefly describe them.

Bits & Pieces 3 General IMG_0899

First of all, as you can see, the aesthetic involved is a different one from the projects I’ve described before.  By and large, they’re designed for mono use – although the headphone amp, based on a TDA2822 chip, is for connection to conventional stereo headphones – and they have a deliberately ‘retro’ appearance to emphasise the simplicity of the lo-fi circuitry and sounds they’re used for.

The circuits are housed in old tobacco and sweet tins I found in my garage: they came originally from my Grandad’s shed, so are very likely older than the speaker.  (Except possibly the Altoids tin, which strikes me as being somewhat more modern, although I haven’t looked into it).

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1.  The speaker enclosure – I use the word ‘enclosure’  loosely here as in fact it has no back to it – is something I saw around the house as far back as I can remember: the late 50’s/early 60’s.  I think my Dad made it: I must ask him.  Somehow I seem to have inherited it; and all I’ve done to it is to replace the speaker itself, which had got damaged over the years, with a new one, which is full-range and 8 ohms impedence; and exchange the connectors on the end of the lead with 4mm banana plugs.

The main use of the extension speaker is to get a better sound from instruments with no line out.  To date I have two of these: the Cracklephone and the Touch-Radio.  Both of these have 4mm banana sockets on them, and the speaker leads terminate in banana plugs, so can be connected directly into these instruments.

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2.  The headphone amp I made some years ago, from a circuit diagram I now appear to have lost.

Headphone amp IMG_0900

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3.  The headphone/speaker switch was also found in my garage – possibly a car-boot acquisition: designed for stereo headphones, but used in this set-up only for mono signals, divided and fed to left and right.To avoid antagonising my neighbours too much, especially late at night, I have a pair of banana leads to connect the instruments to the headphone/speaker switch, via the sockets in the Altoids tin, which allows the headphones to be used in place of the speakers.

3 Boxes IMG_0901

I didn’t manage to show this in the photo, but the speaker leads from the instrument or amp are connected to the banana sockets on the left of the Altoids tin, the headphone/speaker switch connects via the small stereo socket (in) and large mono socket (out) on the front, and the speaker connects to the banana sockets on the right.

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The older Stylophones in my collection would benefit from the addition of speaker sockets: as referred to elsewhere in the blog, most models seem to have additional components in the line-out circuit (filtering out higher frequencies), which gives the line-out sound a different character compared to the tone from the internal speaker.

Much has been written on the Cracklebox, and how it is against the principle of the original design to add a line-out.  As I see it, it isn’t a violation of principle to use an external speaker in place of the one built in to the instrument itself: a wider range of volume and tone is available this way.  And that’s what these Bits & Pieces are about, I suppose: creating sounds in a live, old-fashioned, organic sort of way, in contrast to the modern, synthetic, digital way (also good, of course – just different!).

31
Dec
11

Alternative Keyboards 1

I’m not sure exactly which department this topic should go in, but I’ve added ‘Software/MIDI’ as the advent of these two things has made the possibility of using alternative keyboard layouts very much a practical proposition. I’ve been experimenting with these and come up with some relatively low-cost ways of trying them out.

The purpose of this post is to explain what ‘alternative keyboard layouts’ are – as opposed to ‘alternative methods of controlling synths’ or ‘alternative methods of generating musical notes’, which I deal with elsewhere in the blog. Although there’s undoubtedly an overlap between these things, I’d like to talk here about some specific proposals that have been made over the years to improve the traditional piano/organ keyboard – certainly appealing to those who are non-players of the instruments, but also with a specific appeal to trained keyboard players and those with a keen interest in music theory.

I’ll get into the music theory aspect, insofar as I understand it myself, later; and follow-up posts here will describe the different ways I’ve tried putting alternative keyboard layout ideas into practice.

To begin at the beginning, the conventional piano keyboard, with its line of large white keys interrupted by thin black keys, although a familiar and iconic design, isn’t necessarily the easiest way to play or learn to play music: you have to hold your arms at an odd, straight-on angle to the keyboard; it’s a long stretch from one note to the next octave up or down; you have to move your hands to different positions to play chords in different keys, and so on. Ultimately we might also consider how difficult it makes things if you want to play music using divisions of the musical scale which are different from the 12-note one we in the West are used to.

It was a long time ago, certainly as early as the 19th century, when people began to think of replacing the one-dimensional line of keys found on pianos and organs with a two-dimensional bank of keys, like the bank of keys on a typewriter (or this computer keyboard I’m using now).

It was quickly realised that there would be more than one advantage to this arrangement: notes could be repeated in several places on different rows, allowing the player to find the easiest way to play a particular passage (players of stringed instruments are used to this and wouldn’t want to be without it!); notes which are far apart on the conventional keyboard could be placed closer together, enabling even those with small hands to play chords or melodic passages with large intervals; and, most importantly of all, the keys could be distributed in such a way that the pattern of a particular chord would be exactly the same, no matter which key it was played in, and the pattern of a melodic passage would be the same, no matter which note it started on.

It is this latter feature which leads to the name often given as a description of this type of keyboard – ‘isomorphic’. Well-known isomorphic keyboard layouts were invented by Paul von Jankó and Kaspar Wicki in the 19th Century, and in the 20th Century, Brian Hayden independently developed a system similar to Wicki’s, which one often sees described as the Wicki-Hayden system.

This is a picture of a piano with a Janko keyboard layout. As you can see, there are still white notes and black notes, but not in the same pattern as on a conventional piano, and there are 6 rows of keys:

800px-MIM_Janko_Piano

[Photograph of piano with Janko keyboard at the Musikinstrumenten-Museum, Berlin by Morn the Gorn (Own work) [CC-BY-SA-3.0 (www.creativecommons.org/licenses/by-sa/3.0) or GFDL (www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons’ http://commons.wikimedia.org/wiki/File%3AMIM_Janko_Piano.jpg]

This diagram of the Wicki-Hayden layout shows how the notes are placed in relation to one another. The keys themselves may be buttons, as they are on a concertina or accordion (Brian Hayden was a concertina player), but the hexagonal pattern used here emphasizes the importance of diagonal relationships between the notes, and relates to the method often used in modern electronic instruments of using hexagonal keys set out in exactly this way.

Wicki-Hayden_Musical_Note_Layout

[Diagram of the Wicki-Hayden note layout used on some button accordions and some isomorphic button-field MIDI instruments by Waltztime (Own work) [Public domain], via Wikimedia Commons http://commons.wikimedia.org/wiki/File%3AWicki-Hayden-Musical-Note-Layout.png‘]

You can read about the Janko, the Wicki-Hayden, and a number of other isomorphic keyboard systems in the Wikipedia at:

http://en.wikipedia.org/wiki/Isomorphic_keyboard
http://en.wikipedia.org/wiki/Generalized_keyboard
http://en.wikipedia.org/wiki/Janko_keyboard
http://en.wikipedia.org/wiki/Wicki-Hayden_note_layout

Each of these pages contains numerous links to external sites, if you’d like to know more. I’ll be dealing with some of the issues that follow on from this, such as microtonality (as mentioned above, these two-dimensional layouts also lend themselves more readily to musical scales of more or less than 12 notes) and dynamic tonality in future posts.

You should also check out this site: www.altkeyboards.com/ which is also the home of the program MIDI Integrator, which I have used, and an interesting modern-day electronic instrument using an isometric keyboard (two, in fact) called the Jammer.

The Jammer, in turn, is a development along similar lines of an instrument called the Thummer – which almost reached the point of commercial production – and uses a keyboard called the AxiS-49, which is commercially available (from C-Thru Music at www.c-thru-music.com/cgi/?page=home). A larger version of this keyboard, the AxiS-64 is also produced:

All of these instruments these days are MIDI controllers, and YouTube is probably the best place to see them in action. This lengthy introduction to the AxiS-64 also serves as an illustration of many of the reasons why isomorphic keyboards were invented: http://www.youtube.com/watch?v=D7OeRkXWTtQ. You can also see the Thummer http://www.youtube.com/watch?v=GtzA2UHOr-A and the Jammer http://www.youtube.com/watch?v=GLN4CAl6p7A.

There are hundreds more videos of these instruments and others, including a nice-looking Japanese synth called the Chromatone, which appears to be completely self-contained: http://www.youtube.com/watch?v=in9_ojEnfO0.

The next post in this department will be on methods of creating simple isomorphic keyboards, and the hardware and software I’ve used to create mine.

31
Dec
11

Stylophones

I must say I’m very fond of Stylophones!

The Stylophone, if you’ve never encountered one, is a small, hand-held monophonic instrument played by touching a stylus to a row of metal pads – the edge of a large printed circuit board – laid out like the keys of a piano. It was invented and first marketed in the 1960s, and is sometimes described as the world’s first mass-produced synthesizer.

In my view the Stylophone is an indispensable element in the arsenal of the electronic musician – it’s simple, distinctive-sounding, and most types are available at a reasonable price, with patience, from charity shops or on eBay. It’s also possible to make a number of straightforward – and some not-so-straightforward – modifications to it. I have described elsewhere in the blog some of the ones I’ve done.

Although largely the brainchild of engineer Brian Jarvis, accounts of its genesis in 1967 suggest that the Stylophone would never have seen the light of day without the encouragement and input of brothers Burt and Ted Coleman who, together with Jarvis, ran a company called Dübreq. Dübreq produced equipment for the film and broadcasting industry and their name is said to derive from their specialities of DUBbing and RECording, with the umlaut and the ‘q’ added to give the firm more of an international air (or perhaps, like Motörhead or Mötley Crüe, just to look cool!)

The marketing masterstroke which ensured the eternal popularity of the Stylophone was the engagement of the multi-talented London-based, but Australian-born entertainer, Rolf Harris. Even before production began, the Stylophone was introduced to the world on Harris’s popular Saturday TV show on the BBC, and, it is said, became an instant hit – despite at first being available only by mail-order from Dübreq at the frightening cost of 8 pounds 18 shillings and sixpence, around ninety-five pounds in today’s money!

Over the following decade a number of different versions of the Stylophone were produced. I have a treble – which is all white – a standard black, and a bass – also black. This latter wasn’t a production model, but the circuit diagram that came with the standard showed different component values for all these three types, so I modified a standard to produce the bass register, an octave below. I’ve subsequently modified this to produce a further octave below that – I call it ‘The Double Bass’ – but this is not a modification suggested by Dübreq themselves.

This is a circuit diagram of an early Stylophone. Note the details of alternative components: resistors in the top left and capacitors in the bottom left.

Stylophone schematic 2

There is also a later 1970’s version (the ‘New Sound’) with a fake wood fascia in place of the familiar metal grille. This latter has a feature noticeably absent from the earlier models – a volume control, a useful feature in the days before the ubiquitous earphones. Here is the component layout and schematic/circuit diagram from the booklet which came with it.

Layout and Circuit Diagram

It was not long after this, in 1975 or thereabouts, when production of the original Stylophone ceased; and this might have been the end of the Stylophone story, had Brian Jarvis’s son Ben not had the idea in the early 2000s of bringing it back. By 2007 the new Stylophone S1 was on sale, sufficiently similar to the original to be instantly recognisable, but with some updated features, including built-in input and output sockets and a three-way tone control.

Stylophone S1 2sm

It’s possible to do modifications on all these variations on the Stylophone design, even the S1. Despite the fact that the chip that does all the work in the S1 is very tiny and inaccessible, parts of the pitch and vibrato circuits are available, and the output stage is on a separate PCB. I was able to do some mods on a couple of these.

The ‘New Sound’, based on the very common 555 chip is easier to deal with, and I was able to do a lot with mine (see http://wp.me/p25FoK-10). There are many circuits for 555-based oscillators in books and on the internet, and the 555 in the ‘New Sound’ is easily accessible for modding.

I haven’t done much with the original Stylophones – but these should be even easier, as the resistors which fix the pitches of the notes are exposed, and it should be possible to do things to these without too much trouble.

The biggest problem with the original and ‘New Sound’ Stylophones is likely to be the cost. Since these are sought after by collectors, they can fetch rather higher prices than you might want to pay for something which you intend to experiment on!

Many stars – other than Rolf Harris himself – have been publicly associated with the Stylophone. You can read about these on the Stylophone page in the Wikipedia at http://en.wikipedia.org/wiki/Stylophone, and see pictures of them on Stylophonica, ‘the official home of the Stylophone’ at www.stylophonica.com. You can also learn more of the history of the Stylophone at www.stylophone.ws (or www.stylophone.fsnet.co.uk), the Stylophone Collectors Information Site; buy a vintage Stylophone at www.stylophone.com, the Stylophone Sales Center; or even make your own Stylophone at www.instructables.com/id/A-Stylophone!

You will also find out about the mighty Stylophone 350S, much larger than the ordinary Stylophone, with two styluses (styli?), more notes, more tones and a cunning light-sensitive filter/vibrato control. This also went out of production in the 1970s and has not so far been revived.

Stylophone 350s

These machines – wonderful thought they are, as you can see – can be seriously expensive, and you would probably want to think twice about having a go at the electronics in it without knowing what you were doing. Having said that, like the conventional Stylophones of the period, the electronics will be relatively straightforward compared to modern devices. A bit like cars, really – in the old days it was much easier for the amateur home mechanic to sort out engine problems: nowadays, there’s very little you can do. The 350S has many different ‘voices’ and that intriguing photocell circuit . . . there’s got to be some scope there.

A new type of Stylophone that has appeared in recent years is the Stylophone Beatbox: a drum machine playable – of course! – by means of a stylus, including percussion, vocal percussion and bass sounds, and able to record and replay sequences. I have some functioning ones, which may also be good for circuit-bending, and some non-functioning ones from which the attractive circular playing surface should be useful for other projects.

stylophone_beatbox

I used the case and the keyboard PCB of one of these for a Stylophone project, but not the sound-producing electronics as there were faults with the ones I acquired which I couldn’t fix.

Dübreq’s website at www.dubreq.com suggests there are more Stylophone products in the pipeline, but none, at the time of writing have appeared. Some other websites have been advertising the imminent arrival of the ‘Stylophone Remixxer’, but I’m not aware of any genuine sighting of such an object.

29
Dec
11

How I started

I’m writing this Blog to document some work I’ve been doing in the field of electronic music-making.

I wasn’t an expert in any of these things before I started – and I’m probably not an expert in any of them now, but I’ve learned a lot as I’ve gone on, and I hope if I can pass it on it’ll be a source of interest and in some small way an inspiration to others who are getting involved in this field

When I began thinking about this project I decided to do it in the following way:

a).  To avoid working with computers (until the very end).

I’d used computers extensively in my music before, from Logic for straightforward composed pieces to a variety of other programs for electronic composition or sound treatment.  I expected to return to using the computer in the end, but with the benefit – hopefully – of new knowledge and new sound devices.

b).  To incorporate where relevant some projects I’d started, and mostly not finished, many years ago.

I’d made some guitar effects with a degree of success that could be described as ‘mixed’ – some of them I use to this day, which work very well and can’t or don’t need to be replaced by anything new; some are still around, not quite working the way they were intended to; some never worked at all!

So I decided not to go back to guitar effects, but to concentrate on sound producing devices.

c).  To explore certain specific ‘movements’ in electronic sound-producing, such as ‘circuit bending’ and ‘Lunetta’ devices, and construct some of the ‘classic’ designs along the way.

d).  To explore alternative methods of music input – isomorphic keyboards, game controllers, and other home made devices.

One of the intentions behind this was to create music in more of an informal and  ‘live’ way than I had done using the computer; another was to explore the variety of music- and noise-producing devices now available – usually cheaply in sales, second-hand shops and on eBay.

I also wanted to pursue my obsession with the Stylophone, an early electronic synthesiser of the late 60’s and early 70’s, but recently reintroduced.

I’ve divided the different parts of the project into the following categories:

1.  Modification

In this first phase I would take existing devices and add new features, or expand existing ones.

My principle in doing this was understanding the circuits (to a certain degree) and making appropriate changes to produce specific effects.

2.  Construction

Phase 2 was to build a number of sound-producing devices from scratch, using circuit diagrams and descriptions from books and magazines (I had a number of these collected over the years, and hand-drawn circuits copied from publications in libraries) and from the internet.

Again, a certain amount of understanding of the principles of the circuits would be necessary.

3.  Circuit Bending

In this phase the idea was to take existing electronic instruments – children’s toys mostly – and make them produce sounds they were never intended to produce, mostly without worrying too much about the circuits that produced these sounds and how they were working, which I felt was more within the spirit of the enterprise.

4.  Freeform designs

The intention then was to extend the knowledge gained in previous phases to create new designs, partly modified, partly constructed, incorporating past ideas I had had, but never put into practice and new ideas discovered through experimentation.

5.  Software/MIDI

This phase was to be mainly computer-based, involving programming, which I had not done before.

As it turned out, I was overtaken by events, and parallel with the Modification and Construction, have got involved in some slightly different areas.  However, I’ll write about each of my projects in order, and put them in the appropriate category.




andymurkin

October 2020
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