Help with stripboard layout...

[Late_to_the_party]

Thanks PHOBoS.

My the output is a little noisy. So I'd like to fix it.

However, I wired according to Eric Archer's layout. See image below...

Any idea why this kills the output when I connect these three components to the ground?

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[PHOBoS]

hard to say but something must be wrong if it works otherwise.
Could it be that you used a 220nF capacitor for C1 instead of 220pF ?

[Late_to_the_party]

Thanks PHOBoS...

I am a complete wally. I had failed to connect C1 to C11. Fixing that problem meant when I connected the 'missing' ground to C1, R20 and R25, it worked perfectly.

Now I have a fully working clone. No noise, loud as hell, beautiful long decay. Thanks for everyone comments, this forum enabled me to get this far.

I think I will switch to stripboard over perf board for the other modules, to avoid any more missing links.

I feel I have only just scratched the surface here though. Really want to mod this kick with an OVERDRIVE pot. Anyone have any ideas?

Also, I have just tied Accent to +15v, Is there any point adding a pot to it to vary the 'accent'?

I'm also going to have to make a sequencer, having to press a button for a BOOOOOOOM is getting in the way of making music.

[artilect99]

Hey all -- just thought I'd post my own working copy of the layout in case it's helpful to anybody building this. The original layout by Minus underwent a number of changes over the course of this thread (notably a missing cut between R26 and C4 as well as other minor tweaks) which are incorporated here.

The potentiometer diagram was added because I originally wired the pots backward (Wiring the pots as they are numbered in the Eric Archer schematic will result in them being reversed).[/img]

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[RyBowk]

[artilect99]

Hi ryan -- yes, it uses the original BOM. No components added, just a missing cut on the board and some tweaks (like the output needing to be moved on the top left etc). The tuning mod would require another pot if you replace that resistor.

Incidentally, if anyone is building this as a Eurorack module, I found it works great to just use a jack for the accent, and tie the +V into the switch of the jack, so it gets normalled +12v if nothing is plugged in. Then if you feed this jack CVs it acts as volume control / accent. Jack for trigger in can take a normal 5v gate or trigger pulse in this setup, and longer gates give a more overdriven sound.

[RyBowk]

I now have this built and it sounds great, especially with the tune mod.

[RyBowk]

I did have it working perfectly. After using it for some time I turned it back on and now the kick is at a constant higher pitch? Does anyone have any clue as to why? I have even tried taking the tune mod away and putting the original resistor back. I’m stumped!!

[RyBowk]

All sorted, turns out a transistor leg wasn’t soldered properly.

[artilect99]

Glad to hear you got it sorted out. I'm doing the snare next, I just have to figure out a decent way to mount a stripboard to a 6u eurorack panel (brackets maybe?). Right now my 808 bd is just hanging loose inside my case.

[RyBowk]

After building the kick I just have a cymbal left to do. What I have done for mounting is use a piece of right angle plastic, bolted the strip board to it and used the potentiometers to mount the plastic to the panel. The panel size I have used is the size of the Moog Mother as I have built a trigger sequencer also. I think I will build it into its own case. Thanks Ryan

[PHOBoS]

[artilect99]

Good call Phobos, that hadn't occurred to me... what value resistor should work there do you think?


no problem whatsoever running it off 12v, although it does affect the character of the sound to some degree. Running it at 15v seems to give the best sound and headroom, but 12v is fine.

I'm running mine into a Strymon deco for some tape saturation and compression and it sounds f*kin glorious.

regarding mounting, I was thinking of using some of Ken Stone's pot mounting rail PCBs (although they are 1" spacing if I remember correctly... might be tight) and attaching the board perpendicularly via a right-angled pin header.

[PHOBoS]

I usually use 1K although it depends a bit on the circuit.
Based on the schematic posted on the previous page I think that should work fine for this.

maybe I will give this one a try someday.

[lysergist]

Another BOM update : R26 should be a 100K, not a 4k7