Posted: Sat Aug 25, 2012 1:37 am Post subject:
TR-808 Voice STRIP Boards... Subject description: Hi-Hat, Cymbal, Cow Bell... and beyond
We already hijacked the I'm making TR-808 Voice Boards thread, but this has gone past the pcb's, I figured I should start a separate topic.
Using the original schematics found in the TR-808 Service Notes, I've successfully bread boarded the hi-hats, cymbal and cow bell circuits. The next stage is laying them out for stripboard.
As this is a fairly large project I have divided it up into four separate parts, each built on its own board. This means if you just want to make the hats, you will need to only build the sound source and hi-hat boards. (The cymbal, open and closed hi-hats, and the cow bell all share the same sound source.)
At present I have a completed working stripboard of the sound source. This comprises of six oscillators based upon the 40106 IC, and the two band pass filters utilising the TL072. It's a fairly dense board- I like to pack the components into a small footprint. I've used MKT capacitors because they fit in neatly. You could use green caps if you wish.
The cow bell component of this circuit uses only two of the oscillators and each are tuned with the trim pots. Cow bell tuning A needs to be tuned to a frequency of 1.85 ms, cow bell tuning B at a frequency of 1.25 ms. It is worth noting that to achieve this range I had to change R15 from 150K to 100K, and R8 from 100K to 68K. You may need to change this too. You will need an oscilloscope to correctly tune the oscillators regardless of whether you intend constructing the cow bell or not. These two oscillators are used for the hi-hats and cymbal despite the fact they do not enter the band pass filters en route to the cow bell board. I have also found that to my ears, the tuning sounds better at different frequencies to the ones specified by the men in white coats at Roland Corp. You may want to experiment with this. More about this later....
I'm drawing up the rest of the boards now and will post them here as I test and confirm the layouts first. If I think of any details I have omitted, I'll post updates here.
Happy stripboarding!
TR-808 Hi-Hats, Cymbal, Cow Bell Clones Sound Source TOP VIEW.jpg
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TR-808 Hi-Hats, Cymbal, Cow Bell Clones Sound Source COMPONENTS.jpg
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Here's the next instalment, the cymbal. I tried a few times to get the footprint down in size, but after a build failure I decided to be less cluttered. My previous effort took the electricity around the scenic route! This version is now built and working and comes out about the size of a playing card. There are a lot of traces to be cut so be careful. If you build this exactly as is, it should work as mine does. Incidentally, I'm running this off +/- 12V at present.
I'll post some sound samples and photos soon.... soon as I stop playing with it!
TR-808 Cymbal Stripboard Top View v2.jpg
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Corrected the pot wiring
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TR-808 Cymbal Stripboard Bottom View V2.jpg
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Corrected label to 'bottom view'
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I've learnt a lot over the past couple of weeks (courtesy of Roland Corp) by studying these schematics and notes. I am triggering from a very crude 4017 sequencer experiment I did ages ago. It may be worth while adding something like Eric Archer's diode cap resistor configuration on the input ( I haven't), or Ken Stones gate to trigger circuit to get a nice clean trigger input. Also, I didn't mention about the Accent in. This can be tied to +V if you wish or to a pot wiper with outer legs to + and Ground. I really need to get a better sequencer built.... soon! I'll have the hi-hats and cow bell off the breadboards on onto stripboard over the next week I imagine.
Here is part 3: the hi-hat circuit. Took a couple of attempts to get this working, but it has been built and certainly works . The layout could have been condensed a little further, but I seem to run into trouble when I try to do that... and all to save a couple of rows of stripboard holes! You will need a standard 34 hole wide piece of stripboard for this one.
Please don't feel intimidated if you have never stripboarded before. I cut the board to size using a craft knife/Stanley knife/box cutter and a steel ruler. I make several cuts each side of the board and simply snap when I think the cuts are deep enough. I then mark the underside using a black marker/felt tipped/ Sharpie pen. It is imperative that the tracks are cut in EXACTLY the right place. If you get this right, you are well on the way to success.
Cutting the tracks is easy. I use a pin vice and a 3MM drill bit. I spin the pin vice about six or seven times. Just enough to cut through the copper. Don't drill through the whole board! It will only weaken it. Once all cuts are done, I check it thoroughly with a magnifying glass just to make sure.
I tend to solder the components with the lowest profile first. Keep those resistor legs you snip off- they can be used for the smaller jumper wires.
Well, that's all for now. I'll get some photo's and sound clips posted shortly. Cow Bell coming up next!
Happy stripboarding!
TR-808 Hi Hats Stripboard Bottom View.jpg
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TR-808 Hi Hats Stripboard Components.jpg
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TR-808 Hi Hats Stripboard Top View V2.jpg
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EDIT: Corrected R19 which had been labelled C19 by mistake
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Last edited by -minus- on Sun Mar 31, 2013 10:12 am; edited 1 time in total
Joined: Nov 10, 2011 Posts: 878 Location: Lancashire, England
Audio files: 14
Posted: Tue Sep 04, 2012 2:11 am Post subject:
richardc64 wrote:
You're not really going to clone that P.O.S. "cowbell", are you?
I'd expect no less, everyone has thier own tastes. _________________ As a mad scientist I am ruled by the dictum of science: "I could be wrong about this but lets find out"
The P.O.S. "cowbell"? Oh, that's what Wikipedia refers to as the "spacey cowbell"
I think if you look at the schematics I have linked to earlier, you will see that for a few more components, the cow bell is a bonus voice. As I've laid each voice out on a separate board, you needn't build the cow bell if you don't like it... It's quite OK to make music with tea spoons and rubber bands instead
I just hate seeing effort put into replicating an inferior design for the sake of authenticity. "B-b-but it's Vintage!"
-minus- wrote:
The P.O.S. "cowbell"? Oh, that's what Wikipedia refers to as the "spacey cowbell"
It isn't spacey. It's lame. Sounds like a mechanical door bell on its last legs; a forlorn and miserably lonely plink without the plonk; a Kalimba having only one tine or a toy piano with one working key.
Quote:
As I've laid each voice out on a separate board, you needn't build the cow bell if you don't like it...
Or build it and then, you know, see what can be done to make it sound like what it's alleged to be -- if there's enough room.
Quote:
It's quite OK to make music with tea spoons and rubber bands instead
Touché _________________ Revenge is a dish best served with a fork... to the eye
no hate for the 808 "cowbell" sound here it's probably the most special sound in roland's analog sound palette and imo a mainstay of the 808 - none of the sounds comes close to the percussion they are supposed to imitate, but that's where the beauty of this machine lies...
here some 1982 italo disco 808 bliss (with cowbell )
Thanks for the cow bell links! I liked the 82 italo disco! Imagine doing music which sounded like that, nowadays. It's almost incredibly cool! The more cow bell video was hilarious! hahahaha!
I guess the cow bell does sound a little cheap. It was only using two of the same six oscillators used in the sound source for the cymbal and hats. Everyone tends to focus on that kick drum and the snare as being synonymous with the 808. But maybe it's the extra sounds like the cow bell which give it its personality. ...I think those hand claps might be worth doing too. suddenly I get visions of a HUUUUGE worldwide disco revival
The cow bell has been drawn up as I type. I'll build it today and test that it works.
I don't hate it: I pity it, much like how I pity people with tin ears
Quote:
none of the sounds comes close to the percussion they are supposed to imitate...
I disagree. I think the others come exceptionally close to what they're supposed to be. OK, maracas is borderline, but still not total fail. _________________ Revenge is a dish best served with a fork... to the eye
Here is the final voice... the one we've all be waiting for: The Cow Bell!
A lot simpler that the other two voices. Having built this, it actually doesn't sound that bad. I listened to real cow bells on youtube and I don't think this is that much further in sound compared to the real thing than most of the other voices are. I get the impression that cow bells in general have a bad reputation nowadays. We need to listen to these in context of the era in which they were made. It was a different aesthetic back then. Just look at the font Roland was using on the 808. The orange font I used on these diagrams. That would be seen as a joke these days. Yet Herb Lubalin was one of the greats of typography. That font was cutting edge at the time. I remember using it!
Anyway... this is the end of the line for these. I might continue with the other 808 voices at a later date. Hope some of you build these!
Sound clips will be recorded shortly.... oh... and socket those transistors!
TR-808 Cow Bell Stripboard Bottom View.jpg
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TR-808 Cow Bell Stripboard Components.jpg
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TR-808 Cow Bell Stripboard Top View V3.jpg
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V2: CORRECTED LABELS TO COW BELL INPUT, NOT CYMBAL INPUT AS PREVIOUSLY INCORRECTLY LABELLED V3: EXTENDED JUMPER FROM RAIL 16, HOLE 27... TO RAIL 17, HOLE 27
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Last edited by -minus- on Thu Sep 20, 2012 9:08 am; edited 3 times in total
I don't hate it: I pity it, much like how I pity people with tin ears
Quote:
none of the sounds comes close to the percussion they are supposed to imitate...
I disagree. I think the others come exceptionally close to what they're supposed to be. OK, maracas is borderline, but still not total fail.
Here's a quote from Kodwo Eshun's More Brilliant Than The Sun, which I like a lot:
Quote:
There are no drum-machines, only rhythm synthesizers programming new intensities from white noise, frequencies, waveforms, altering sampled drum sounds into unrecognizable pitches. The drum-machine has never sounded like drums because it isn't percussion: it's electronic current, synthetic percussion, syncussion. The sampler is at first termed an "emulator," as if it does nothing but imitate existing sounds. Calling the rhythm synthesizer a drum-machine is yet one more example of [r]earview hearing. Every time decelerated media writes about snares, hihats, kickdrums, it faithfully hears backwards. Electro [music] ignores this vain hope of emulating drums, and instead programs rhythms from electricity, rhythmatic intensities which are unrecognizable as drums. There are no snares--just waveforms being altered. There are no bass drums---just attack velocities.
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TR-808 Voice STRIP Boards...
. The layout could have been condensed a little further, but I seem to run into trouble when I try to do that... and all to save a couple of rows of stripboard holes! You will need a standard 34 hole wide piece of stripboard for this one.
it's probably the most special sound in roland's analog sound palette and imo a mainstay of the 808 - none of the sounds comes close to the percussion they are supposed to imitate, but that's where the beauty of this machine lies...
