Adventure in Soundland

Quick little post here. Friend Felix sent me a link to a guy called Moldover who built an optical theremin into the jewel case of his latest CD so I went looking for optical theremins this morning. Well, I didn’t want to be so obvious so I went looking for light theremins.
First one I got I fell in love with and I’m thinking about doing something called the paper bag circuits. Long story but simply put I had a bunch of the kind of paper bags you get pies in, new and un-used, and when findin’ small circuits that didn’t require an A4 I picked up these paper bags. The first one was a speaker as a microphone circuit and this one is an optical theremin. Basically they are small and simple circuits where the schematic, parts list, and the working out of the etching for the PCB can all be done on one side of a paper bag. Whats come to mind is that I could build these little knee jerk reactions to over-complexity and mount them in eclipse mints cans and berocca tubes, have a number series thing going on, and sell them as artworks on Trade Me.

Complete, of course, with the original hand drawn paper bag.
The simplest little light theremin.

Okay, I haven’t done the TV yet. I’m waiting on getting some more bulldog leads so I can isolate the switching to just have the TV on but also remove the radio and tape cassette. Originally I wanted them all on at once but wiring it up so they are all on is beyond me so I’m just going to use the Cathode Ray tube and put it in another framework… somewht like the screens in the movie Brazil.

So I’ve finally gotten around to a few things not the least of which was hooking up the boss pedals and spending a bit of time with them. I’ve got a DD-7 digi delay and the RC-2 looper and the possibilities are nearly endless but it’ll be a while before I get my head around them. You know, read the manual as much as you can, even though none of it makes much sense, then go play with the thing for a while then back to the manual where it starts to make more sense… and on it goes.

As for setting up the recording… it doesn’t work on one channel so I’ll have to go through the mixer and figure out where but I’ve an idea and it should be simple enough to fix. Other than that I’ve got to do a switch block on the outs from the PC so I can switch in a simple amp when using the PC for browsing and stuff because otherwise it’s a hassle to switch mixers and amps and the whole caboodle on and off each time… and who needs a valve amp for U-tube clips?

So what I have for you today is the toy thing. In-organic is on again and I picked up a few more battery powered audio toys. Last year I tried sequencing them up but was having problems making them switch as the little toys work on pulsed DC and if you use a transistor to switch them the base voltage interferes with the pulsing DC accross the collector and emitter. I eventually realised, or was told, that the mosfets in a 4066 would do the trick where the control voltage, on the gate, is not interfering with the connection between drain and source. Last year I’d built the sequencer but it didn’t work with the toys so I used it on a drum machine… that kinda works but even that needs work. In the interim I learnt more about 555’s, more than one ever wants to, but now I pretty much have them sussed so I’m having another go at the toy thing.
Shit, I can’t copy and paste the pictures for some reason, they copy but won’t paste into this page… bugger. I’ll restart later and come back to this.
I can do normal copy and paste from here into the address bar so it must be the photbucket site. I couldn’t get the old uploader going until I un-installed flash so maybe something else in there site is fucking me up.

There you go… it works if I open the picture file on its own page then copy the link. Bloody internet. It’s becoming like you bloody need to be a techie.
Anyways above is the schematic. Top left is the power supplies for the toys which run on 3V and 4.5V DC and you can’t get regulators for that voltage easily so I’ve used a dual opamp to divide off the voltages and buffer them out at a low impedance. It’s what we do with a spare opamp section to create the bias for them working as signal amps but it works just as well for a regulated voltage. They should also have a cap, 22-200uf, sitting on the voltage divider from the divided voltage to ground.
Below that is the 555 which is kinda normal except for the 1N914 diode across pins 6 and 7. This shortens the on time and makes it constant so the off times are what changes. The toys just need a quick jolt to get them firing so maybe the 10k from he power rail could be lessened to about 1k or so which’ll quicken it right up. So the diode allows the cap to ground, off pins 6 and 2, to charge up as fast as it can with an almost direct voltage but then it discharges normally through the pot and this sets the off time. Actually there is an amount of time that caps take to charge that is dependant on the size of it so maybe I’m better going to a 4.7uf and a 10 uf and raising the pot to 500k.
So the thng fires off through pin 3 and that goes to the clock of the 4022 which basically cycles that pulse through 8 outputs. The outputs goes to the control inputs of the 4066’s and each time a pulse reaches a control the contacts go from a super high resistance, 100’s of megs, down to almost nothing, a few hundred ohms, so effectively become a switch closed.
To the far right and bottom is a diagram of the mixer to take all the signals from the toys and mix them all to one out. The thing is that these little toys actually use a bridged output which means the signal is divided between two amps, one does the positive swings and the other does the negative swings, from the bias point, and these are combined in the speaker from the 2 outs. What this means is there isn’t a positive out and a ground so I thought about it and realised I could put a voltage divider between the two amp outs and then take the signal from the middle, chuck it through a cap to take out that pesky bias voltage then into regular summing resistors. I tried it and it works. If I discover that one of the toys isn’t bridged I’ll simply go through 1 10k for the hot.

Heres as far as I’ve got. Two etched PCB’s that suffered somewhat in the etching process but theres enough copper to do the job. Saturday today and Monday night is when I want it to be playable.

The only other thing I’ll be doing is having the switch outs on the 4066’s wired up to RCA plugs then have the toys on 2 x 4 banks of RCA sockets. This way I’ll have a cheap patchboard to change the sequencer order or cut what I don’t want. It’s going to be absolutely nuts through fx… this cheap and nasty little sample player.

Bit bored today so as I was going through the experimentalists anonymous forums and I came across the “turn your old TV into an Oscilliscope thread” in the articles and tutorials section.

Basically it’s all there and you simply add a switch and an input to the TV and way you go. I’ve cut the wires and isolated the vertical ones and the horizontal ones but I’ve yet to determine the grounds. I’ll do that tomorrow. What I’ll do as well is isolate where the amp is and fix it so the signal in also goes to the amp so it really is sound and vision. The old TV I’m using was given to me by Blind Shaun and has a radio and a cassette player/recorder so I might have to do something iinteresting with them as well. The tuning for the radio is the old method of changing the capacitance in a tuned L/C amp so maybe I can get a filter of some sort together that will change the capacitance dependant on the signal in. Have to think about that one!

This is how to do it

As for the tape maybe I’ll be able to switch the play/record head and erase head wiring so I just have play and record and then just put a loop in the cassette.

I don’t think that normal guitar levels going to do it so getting it up to line level with a booster, what are they called when…thats it, followed by a buffer and maybe even a tranformer coupling for the input as there might be quite a bit of noise on the TV’s earth.

Have Fun… and be careful out there! (remember Hill St Blues?)

I went and got all the recording stuff outta the dusty corners where it’s been sitting un-used for the past few years, waiting for me to build a room for it, so I can get some of these instruments recorded. I haven’t tried it yet but no longer is it a matter of just plugging in the little bookshelf speakers. Now I have to turn on the mixer and then the amp and fiddle with settings on the soundcard.
Last time I used it I couldn’t play and record at the same time, which I know seems stupid, but thats what happened so hopefully this time I’ll be able to have it do what I want. I know it seems weird but the thing is that my mixer is designed to be used with the previous generation of this soundcard which means that the in’s and out’s for playing don’t mix with the in’s and outs for monitoring. I think people had problems with normal mixers which don’t have almost two mixers in one, one for sending to the PC and the other for return from the PC so they had feedback while mixing the send and return on the mixer bus. I solved it by designing my own mixer but it seems the soundcards changed to suit normal mixers… I’ll try and figure it out.

PC in a box to be sealed off from the world, with a fan and an air duct to another room, with a rack of stuff I don’t think I need anymore.

As for the insiders guide to happiness featured in the last post. I got another shock off the earths and finally realised it was the power supply I built and didn’t check. There was solder from the neutral to 0V on one of the transformers so when it was all plugged in it was safe but as soon as I pulled a lead out I’d get zapped from the voltage sitting on the neutral wire and then being on the earth. Stupid me huh! So I’ve replaced one PS cap that was round the wrong way, on the insiders guide to happiness, taken out a 6V max IC that was being fed 9V and replaced it with something that’ll work at 9V and turned another IC around that was in backwards and also changed out 4 transistors with some that are supposed to be in the particular circuit as opposed to ones I put in which won’t supposedly work… oh and corrected a circuit blunder on the same circuit. Bang, no wonder I got shocked making so many silly lazy mistakes.

On the final stretch. Just finishing up the electronics then rip it all down to sand off all the rust and coat it all in something that’ll last. There’ll be three knobs to control volumes. One for the stainless steel “gongs” which are mic’d by electret mics up and under the gongs. Another for the aluminium “plates” which are piezo’d and again a clean sound. Then the volume for the Ringing Oscillator sounds which are triggered by the another set piezos on the “plates”.

What I might do though is cut into the hot signals and put in a switch so I can switch things on or off, or have both on (with the “plates”) as well. Thats five DPDT’s for the gongs and eight centre off DPDT’s for the plates. There are trimmer pots accross each ringing oscillator amp collector to base to control the amount of feedback and they could be used to set volumes accordingly but the whole point, which wasn’t one at the beginning but has become so, is to echo the old early eighties drumbeatboxes which weren’t very adjustable anyways and given I have three volumes that means three outs, unless I sum them up to one which I won’t, and that means three paths to the mixer so lots of room for FX.

Next up is getting this thing to work. I won a monthly contest at The Forum but it’s never worked so I’m going back in. It’s signal in to a random number generator, RNG, and a analog bit crusher, ABC, and an oscillator all in parallel then summed up and sent out into the world. Shouldn’t be too hard to fix up and get going, fairly simple circuits.

Drums are hard for me to play. That simple. And then compound that with the fact that building something, without electronics yet, that is then very quiet and you have my first embarrasing performance. Yesterday arvo I made this. Yesterday night I played this.

It’s setup for use with piezos, not attached yet though, that drive a bunch of the previously mentioned ringing oscillators from an early eighties drumbox. After playing it last night and reaching a threshhold of embarrasement because it wasn’t loud enough and highlighted my inability to play with two hands I’ve realised that, on one hand it needs more dangly shimmery options but also it’d be a good idea to mic or piezo the “tins and pots” for their actual sound and the beauty of that is that I won’t need to summ or mix all the different piezos or mics, electrets, because the sounds all come in separately so I can just parallel them all up to the same preamp, while on the other hand technically I need alot of practice being a drummer.

So I had what amounted to a discouraging performance where I felt I somewhat let the side down but in getting the above photo I had to get the offending article out of the back of the car and upon taking it inside, setting it up, and having a little play I was again in the land of wide and open horizons and what little depression I felt entirely subsided. With this setup, incl all the electronics, I’d like to look at the territory between a ringing oscillator and a regular oscillator thats on all the time. Oscillators that ring for a little longer than a drum beat but not to the point where they become continuous.

So with this foray into beats I suppose an underlying dream is coming to the fore and the realisation thereof is becoming more apparent. This dream entails getting together all the instruments and electronics neccessary to create a performance of sorts with a band of similar miscreants to myself that could go around visiting schools and offer performances and a following workshop to the kids. Of course, the whole thing would have to be theatrical as well, costumed, staged etc, but it’s still a little way off but with this particular foray I can actually smell the future of it coming into being. Echoes of future beats coming back to me!

Yesterday was interesting. I took two friends, Lin and Doug, to a Vit S concert at this little bar thats part of the New Gallery complex in town. I wanted to introduce the music I’m into to Lin, Doug has already had the Vit S intro, because it was important to me that she experienced what drives me these days.

Me and Lin have this weird relationship, well it’s not weird for us, but outside it may be construed as such, because we were close as soon as we met and the closeness was surprising and a little scary because it all came straight out of the blue. There were also some wierd connections to her life that I came to represent and finally we approached a clairvoyant and got the inside track as to what we were and are to each other. Suffice to say we’re close and it was important to me that she get an impression of the gang I hang with these days.

So we all had different cars, we’re humans of the first world afterall, and parking was a little difficult but they arrived before me and were outside when I got there. They didn’t want to go back in but I led them in, the concert was underway, but after a while they decided to leave and I stayed. I wondered if I should go chase them and find out why they didn’t like it but I did like it so I stayed. Thats kinda why I like the Vitamin S thing. Questions are raised about likes and dislikes as well as the “scene” having no other contemporary mode of behaviour, it’s always kinda floating, so behaviours are simply what goes down and again more questions are raised. I have gotten to know myself and my relationship to society alot better in the brief, almost a year now, that I’ve centred myself around its peculiarities.

So the concert finishes and I meet them outside and their reasons for disliking the atmosphere are thrown at me. I’m not beautific so I throw back why I like the place and argue the reasons for what they percieve one way I understand another.

Boring, pretentsious, lacking in dynamics, melody and a beat. Oh no, here we go. We go to dinner and the argument continues. I try to just let them convince me of the validity of their arguments, and they are valid, but I can’t help myself. I argue for the thing that holds alot of weight these days for me and while this ensues I realise the details of why I like this music and how it’s taken time to embrace. It’s alike most aquired tastes that seem completely yucky at first but we instincively know theres something worth getting used to and when we finally do we see the subtleties and know our challenge to ourselves has been worth the effort.

I though, am brazen in my argumentativeness. Why do you think this music is pretenscious? Why do you need rhythm and melody. At some level isn’t all sound and noise music? This makes them more entrencehed and I am left feeling a little bereft. I think they might be right but then I remeber my first ever dose of Vitamin S, I’d forgotten about this, which was a few years ago when they were still at the Odeon. I’d thought exactly the same thing and walked out thinking “what a pretentsious bunch of wankers, can’t they think of something more interesting to do than all that noise? Wheres the melody and the beat that would make it more accessible?”

And then I realise that I also thought exactly the same thing about some of the dance being done by Val and her modern dance friends at the time when I was actually ready to embrace the way of the Vitamin called S. She kinda encouraged me to go to the Vit and with her there I found the time to accept it. It was also at a time where I was interested in branching out as I’d gotten back into electronics and instrument making and Vitamin S just opened up before me as an enviroment made for me to jump into.

So with this argument yesterday alot of stuff I hadn’t even thought of was brought to the fore as I struggled to understand why friends alike in so many other ways found this particular arena of my life a complete waste of time and energy.

Beauty is in the eye of the beholder. From this isn’t it reasonable to assume that for some ears what is construed as noise for some may be heard as music to others? It seems obvious when it’s written down then why is it so hard to lift oneself above ones preconceptions of where boundaries lie and open those to new ideas. Maybe it’s because the idea of music is one of beats and melodies… patterns. The idea of being able to percieve patterns within sound that are harmonious with our notions of emotional response. If those patterns become obscure and obtuse, not recognisable or able to be repeated, does that stop them from being patternable. Does it stop, or do we stop, an ability to give ourselves to complexities that may reveal depths to our characters that we don’t want to or aren’t ready to acknowledge. All these questions were raised for me last night as I realised that my friends were seeing and hearing something they weren’t ready to accept and what was apparent to me was the ease with which they gave reasons for that. I realised I had aquired a taste for something that others could not and did not find appealing. I don’t blame them for that for I was in exactly the same position myself years ago.

At the same time I am left wondering about other aquired tastes and the phenomena behind them that it’s not so much what we do, be it cover ourselves in tattoo’s or have multiple piercings, or decide to ride skateboards or go surfing etc but that in choosing a particular thing, on one hand because we identify with it in some un-acknowledged and un-understood ways, but also in that acquiescence we decide to follow a fate that allows us to find out more about ourselves and our relationship to others. The more obscure the choice is the more we seem to distance ourselves from others but at the same time see the underlying similarities in all our actions. Our gang may be obscure and have few members but it’s still a gang and isn’t it possible that it’s only reason for being is to learn the value of kinship. The stuff itself, being truck enthusiasts or crochet circles, is mere detritus, interesting detritus I’m sure in all the vagaries of this coming together but underneath I think it’s all about testing ourselves and accepting others and being able to let others be who they are while we become who we are.

This then raises again the question of the actions undertaken within the group. I find that within Vitamin S I have to suspend judgement almost all the time. I can’t define that something is good or bad because then I have to question myself why I decide that it’s good or bad. What is it about a certain grouping of sounds that raises fear in me or makes me feel uncomfortable and again, or almost reciprocally, because I am dividing it into the one that is me, what is it about other groupings of sound that feel good and allow me drift off into worlds where all possible things seem open to me.

This gang is, for me, not one where I can drop into an easy un-questioned version of myself, I feel that in this gang I can question the role of myself and try out new clothes. But not only that. I have to question why I find myself even in those particular clothes. It’s a new gang. It’s like the trial period before a gang realises it has a patch to emblazon upon it’s backs and write the charter of definition. It cannot be categorised at conch records unless it’s under weird shit that hasn’t decided what category it’s in yet… which may actually become the new category… now that’s a good name for a band that added beat and melody to this noise stuff and made pop songs for mass consumption…”The New Category”

I just went to the Vitamin S website to grab a picture to finish this off and picked this one straight off the front page and now I’ve read through the above and corrected mistakes I looked at the picture and realised one of my old paintings is in the background. It’s from years and years ago, the photo and the painting, and, Gosh and Good Golly, I just love serendipidty. Would hev been back in about ’94 when I had an exhibition at the Odeon and didn’t even know Vitamin S existed.

Last night we had an impromptu workshop ’cause this guy, Chris from Wellington, is leaving for Toronto in Canada, and I didn’t, yesterday morning, have a new instrument to play. Why would I need a new instrument you ask when I can just get out an old one? Keeping it fresh is my answer, keeping myself guessing is another way of putting it, and this was brought home by my recent viewing of a couple of DVD’s I bought years ago but have never gotten around to watching. ” The Year of the Horse” about Neil Young and Crazy Horse by the Jim guy who did “Coffee and Cigarettes” (and what am I doing right now?) was watched last the night before and Neil spoke at length of the need to throw stuff away as soon as it became easy. As soon as a song reached it’s beautiful best… drop it from the set and add another one that needs work. I remebered that I do that myself. As soon as I get good enough at something to start paying some bills, or have the intricacies of something worked out where I can do it without wondering what else is possible, I drop it and start in on something new. I love challenges and being on unseen or touched horizons. I explore simply for the buzz of finding the new and not for the rewards it may bring. The life of Zen, Baby!
So anyways a month or two ago I was wandering through Windworld’s and Odd musics link pages and I found the waterphone. Couldn’t really see what it was but it was interesting none the less. Then the other day I gave myself a few hours, well half an hour before closing, at the library in town and , low and beholden, was a really nice bunch of pictures of the waterphone in a really nice book about percussion instruments. Oh yes, I understood it and I could make it!
The next day I took a trip to see my Dad to borrow some cash but also to check out the two great and two middling Sally shops (opportunity, church etc) in Glen Innes for steel baking pans so I could build a waterphone. Nothing very good but I did get two that might work at a pinch but not really enough to get me motivated. I could go into the construction details of steel baking pans and dishes but suffice to say some of them do the job for baking but for what I want to do with them they may prove unworkable… after I’ve started to braze them into what I want.
That night out comes another DVD. Bjork doing unplugged and what turns up? A waterphone in all it’s glory and now I have all I need, bar the right baking dishes, to do the job. Then yesterday morning I decide to drop in at a second hand shop in Papatoetoe, where I can droll over the beautiful but overpriced aluminium kitchen stuff they have, and what do I find but the absolutely right stuff in steel bakeware to build a waterphone.

Yesterday morning I awoken thinking I needed to work like a bastard all day to do this other thing which might have occured but it would have been a real stretch and not very enjoyable when I run out of milk and coffee so fuck it, I’ll go buy some and maybe on the off chance the second hand shop might have something that’ll motivate me… and it did. Got home and worked for about an hour to make this weird thing.

Just two baking tins, or plates ( without rolled seams, thats important), a bit of tubing and some 4mm bright steel rod.

Because it was called a waterphone I was under the impression it had water in it, I think that was because I had some fun last week playing a pot while I was doing the dishes, scratching the bottom with a fork, but I’m not absolutely sure what the book at the library had written about it but suffice to say the original makers name was Water…. Waterphone. Anyways I wasn’t going to put water in mine so I used Turps. Very interesting piece so if you’re any good which bronze and very thin steel… have a go!

Mums gone, in Canada, so I’ve moved my dusty old recording stuff into the Lounge and hopefully will be into adding mp3’s before too long.
Drum Machines.
The old one did kinda work but the sequencer needs work and that taught me something about how to manipulate 555’s to do what I want, and possibly how to throw 4017’s into oscillation… if thats even possible.

The thing with using a 555 as an oscillator to drive a counter to drive drums is that the on times need to stay the same while the off times get shorter as the rate increases. I read up on the 555’s and I reckon I can get it going as previously hoped.
But then I’m now into ringing oscillators and I design up a new one, well steal schematics and adjust them slightly, so heres a new one with most of the beats from a “Soundmaster Rhythm machine” and the rimshot from a Boss DR55 and just to be tricky I’m not sequencing them up to fire as according to how they where in the original equipment but taking my usual big leap of faith and deciding they are going to be fired by sending a pulse into them from piezos mounted on acoustic thingies.

So I’ll mount all these aluminium “ringers” so I can play them acoustically then, at the flick of six switches, bring in the piezos attached to fire the electronics…

But thats not all! Golly, as if I haven’t enough on my plate. From an old seventies electronics mag that my good friend Valerie found in a pile on the side of the round on our way out to Steve and Cindy’s and their six kids out in Orere point… The simple synth… with added ribbon controller and relay switched attack and decay. Thanks to the good chaps at experimentalists anonymous for their invaluable help. I deal in lots of invaluable actually!

In hindsight there should only be serendipity defining the reason.

So Mum’s just left the country for her yearly sojourn back to Canada and this leaves me with 8 weeks to scatter my stuff all over the place and actually get some stuff done. I know I’ve written about all these other new projects but this morning I decided to get an old one out that wasn’t finished and it wasn’t finished just before she got back last year.

Out it came this morning and it took me a little while to find my notes on it and it’s all fairly straight forward to get together and into a box. Of course, as soon as I looked at it I realised there were easier and simpler ways to do what I’d intended but thats what happens. The drum sounds themselves are from a schematic from a book both written and published in India which used to be available from Jaycar and has a bunch of archaic schematics that use hard to find and obsolete parts from the sixties and seventies. This one is the least archain except for BC148 transistors which are very hard to find but it doesn’t matter because modern equivalents will do the job regardless. The other tricky part is the 100mH inductor but I happened to have a bunch lying about that I swapped for something or other years ago because inductors in tone circuits are quite useful… including filters like the wahwah. Heres the schematic in all it’s olden day glory. If you can’t see it properly just click on it to go to the Photobucket site where it’s held or copy the image location and paste it into the browser address.

The way it works is by using something called a ringing oscillator which is an oscillator circuit that rings for a bit then dies. The infamous old Roland beatbox from the early eighties was made using the same technology and I’ve got the schematic for that somewheres and is a little fuller than this particular rendition but still was fairly blippy and beepy. This technology or angle I suppose was followed up to the end of it’s useful life which was heralded by sample technology which rendered this type of circuit somewhat redundant… UNTIL NOW!

Seriously though, I’m going to get this going to reaquaint myself with this ringing osc gyro stuff and look at making the oscillators ring a little longer.
So a drum sound generator device is the first part of the drum machine and the second part is a sequencer of some sort to fire the individual ringing oscillators and sequence them up to some sort of ordered output.

Above is that which is the drumatic! The board at the bottom is the finished indo beep and blip maker, six different sounds for triggering, and above that is the incredibly complex sequencer. The sequencer itself is pretty straight forward but my implimentation is as archaic as the Indian drum sound source. Essentially it’s a 555 to set the tempo, which can be adjusted from 10-140 bpm and then the trigger signal goes to a rotary switch which chooses between 4 different 4017 decade counters set up to count to 8 then reset and begin again. Each 4017 then has it’s own 1-8 count which then goes out to a transistor which eventually makes a connection to fire each drum sound. On it’s way to each drum sound the single out from each transistor goes to a switch block that can turn on each of the six sounds. Very confusing I know because I had to make it but suffice to say I can manually choose between 4 basic patterns then assign those patterns where I want. There is a logic going on and it’ll be alot easier when I can transfer that logic from a hands on switching and choosing system to something that works with actual electronic logic, which I’m not at all familiar with… as yet, and may even prefer the type of interface I’ve built here.

Once this is up and running I’m going to breadboard various other ringing oscillators to see if I can get them ringing for longer.

Meanwhile I’m having a bitch of a time getting this amp to work like it’s supposed and I have no idea why.

It’s a single IC amp, a TDA1519, which I bought originally as a kit from jaycar, which is designed for 12VDC car systems and does about 22W into a 4 ohm speaker at 1.5A but the bloody thing just doesn’t want to play. I had it going at 15V but it was only pushing about a half watt so I took it back down to 12V and now it does nothing. I also realised the chips I had, TDA1519’s, were actually quite different from the TDA 1519C which the kit came with. The TDA 1519 was a 6W + 6W, or 12W in bridged mode, while the “C” prefix is a later developement at 11W + 11W and 22W bridged but the pinouts the same and the only difference is the current draw to get to the max out. At this point I’m going to put the original chip back in a see what happens because I’ve got a power supply that works sitting on a 2A transformer so the thing should be getting all it needs and the max voltage for both chips is 17.5VAC so I might put it back up to 15 as well.

I’ve got these huge long pipes that they bury in the roadsides to carry away our debris and I’ve been half thinking of doing something musical with them for a while so last night as I’m winding down from the good vibe energy transmitted to me during performance I was looking on the ‘net for the math involved in where to put holes in pipes to make them play notes.

Everything I found, calculators and stuff, was for itty bitty flutes and stuff but I reckoned I could use them to factor things up by ten or twenty or whatever, it’s always only about scale after all. But then I found something that listed the speed of sound and frequencies starting from C(0) and the lengths of the wavelengths. You’ll find the table here
Basically it’s just about the speed of sound divided by the frequency then halved to give the mid point of the wavelength and thats where you note will lie. Then the hole size, as far as I can understand, is dependant on the interior diameter of the tube and making is bigger raises the pitch as well as having a hole a specific size and lifting it, alike some saxophone holes which are raised above the body while some are into the body.

So the idea is to place a speaker on the end of this tube and play white noise into it and then tune it up using the fact that white noise contains all the frequencies and the holes will boost specific frequencies over the others similar to a tuned drum which is usually white noise.

I found another website page about the maths of this and as usual instead of just explaining how to do it the boffins were just interested in how many maths calculations they knew. The underlying principals are really straight forward so why does one have to cut through all the chest puffing to find the simplicity underlying all verbosity.
Guess who really knows what the speed of sound is at sea level and at the medium temperature for a specific season?

So what I’ve kinda figured out is a pipe about 2meters long tuned to A minor and C major diatonic and having the holes out of PVC or aluminium pipe coming out on the radius line and tuning them up then having caps on them that are actuated by foot pedals. I’d most probably play voice into them, through a speaker, then have a mic at the outer end and amp that to play a speaker as a plate reveb below or above it all so this may be my biggest instrument so far. Voice because there were two guys last night doing vocal stuff and it’s about time I worked that way given it’s the most accessible instrument we all have and the most capable of a myriad of different sounds, even mine with about 1/2 an octave.

This stuff was my first option but then I realised I’ve had this lying about for ages.

The aluminium will be much easier to attach things to, and more precise, and I’ve been meaning to try out some aluminium brazing rods I bought at the KUmeu Hot Rod show a few years ago.