yes most certainly but it can also lead to misunderstandings when building, if multiple resistors are about, you might look at 1 value and attribute to a separate box. for instance in this build that would have happened as to how tight it is
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Super that will help a lot 
Been having fun using the BSP to control the MIDImodule for two drums on SQ1/SQ2 and another via a gate on the SQ/drum … then pipe through the FILTGRRRRR for a bit more GRRRRRRR
Right, but if you put the value inside the box, that’s probably what you’re looking at when building, so not so much chance of mixing it up. Values in, refs out. I’ve been doing it that way lately.
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Audio quality poor. Musical Quality Poor
But this is progress from general noise to something…
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Still waiting for some screws to turn up to fix the modules and stop them dropping out…
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good pairing! Squelchy Grr distortion really sounds neat with those drums.
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Go velcro strips until you settle on a layout.
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I have extra cables now so layout does not matter too much, just got to be a bit logical to stop spaghetti.
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sounding good! get to the bottom of the feedback yet?
not yet, not had time… can’t be anything major.
is it just me or are c12 & c16 transposed between schematic and pcb? not that it makes any difference.
Have isolated the resonator from the input and output and still getting feedback.
Tried a different 4011 with same result.
So now just goign through swapping out each component.
Well I finally ran into a problem that isn’t readily fixable and thought I’d add to this… I built this module during one of my builder’s livestreams and didn’t deviate from the design as I’ve done before.
There is a 60hz hum that only appears in the noise circuit, it seems to trigger, but it’s really faint and* doesn’t sound like the module should.
I’ve gone through about 3 hours or so of non-stop debugging to no avail.
I’ve tried replacing Q,1,2,3, that didn’t help, tried all new opamps and 4011AE (using the AE version) and so far nothing at all… the noise/snare still seems to trigger to some degree, but I can’t really tell if it’s fully working or not…**
The 60hz hum is the only thing present, and only from the snare/mix out, and after removing R49/52 to take the noise circuit out, can confirm that the hum is coming from noise circuit only. Though haven’t located the source yet.
I will post more when I’ve had more time to dig with my scope it.
But just as it is, everything works beautifully, minus the noise circuit, can’t figure out what’s going on there yet.
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Here’s the demo of what I’m talking about
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tried tracing it with a scope?
seperating the noise from the snare final output ( if possible ) to narrow it down?
Rob
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I haven’t had a chance yet, thought I’d run the scope across it later today after I’ve had some sleep XD
But I have tried taking the noise circuit out of the mix and it removed the hum, specifically R49/R57.
Honestly I’m at a loss, even tried turning my a/c off as a last ditch effort and honestly I can’t find the problem without the scope. So that’s going to be soon as I can rest up enough to think.
Will update on my findings soon,
-Dave
snare is a combination of low (or high ?) bongo + noise, here it’s seem it’s the noise + kick bass drone ? if you change the pitch drum during the same test, hum pitch change ?
test to change the pitch of the bongos during the same test too
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That’s what I thought too, but nothing changes the tone of the hum, it’s constant.
Even during the odd power waver that happens sometimes when the A/C kicks on, the VCOs normally dip a smidge and then go back, this hum didn’t change at all.
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I don’t really know much about this circuit, but whenever I see inductors and capacitors connected together I think of oscillators - can you try removing L1 from the circuit?
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Okay, so as it turns out there’s a few things I learned today, one. I don’t need to scope it. It works perfect. In fact I also learned that a certain 2N3904 doesn’t make noise, but the other one does.
The 2N3904 B331 doesn’t work
The 2N3904 H331 does work perfect.
TLDR: Twin-T Drummer works perfectly, it actually works so good that it’s very sensitive to other modules in the mix as to if it makes the noise it’s suppose to make when triggered or not. Go figure. XD
Secondly, the hum was in fact the 60hz power hum, it’s coming from either the mixture of so many ribbon cables, or one of the other modules, I have narrowed it down to a few modules that were adding in the hum, to check them for any problems…
Also, just in case it’s overloading the power supply, I started plugging in from 1 and worked up until the hum came back, it doesn’t seem to matter which module, the hum comes back after so many have been plugged in, but there is most definitely one that is making things go crazy, I am going to trace that out next.
EDIT: Most definitely the power… it wasn’t getting enough current so I gave it a 1500ma supply instead of 1A and it had a lot less trouble, went back to full blast.
So all this, my apologies.
Down to my own idiocy thinking the one supply could handle all that… I mean it’s not made it to 2 full rows yet so I didn’t think it would need the extra juice. But it’s time to build the second power supply already.
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Cool ! 
There was a discussion recently and I referred to these some consumption figures for some of Sam’s modules, interesting to look at if you haven’t already.
and yes it can go quickly to exceed 1 A, it is better to count larger to be sure. Personally I use a 2.5A for 2 Frequency Central power supply in series (near of twenty modules).
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