Here’s my attempt at the schematic if you want to compare:
Looks the same, just way more readable.
In order to get a 1µF I’ll try this: Can you make a non-polar electrolytic capacitor out of two regular electrolytic capacitors? - Electrical Engineering Stack Exchange
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You probably have tons of 100nF (like everybody here 
)
Why not put a few in parallel ?
10 will get you the required 1uF,
but 4 (for easy breadboarding with the 5 holes per strip) should be fine to test the circuit.
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Of course I do, because someone told me to get them 
So I put 10 100nF in parallel on the + and minus strips of a different breadboard and than hooked that up with jumper wires.
With a 1M resistor on the attack, I could see an effect (<1sec)
I put 24 caps in parallel, put 1M+640k on attack, and I only roughly get 2 seconds attack (according to the LED, I’m using it without input and output for testing, only the push button).
Am I doing something wrong or is this basic EG supposed to only have this short times?
See, they are useful 
I never built the simple EG, but that looks really short to me.
2 seconds attack is really pretty slow.
The time constant you should expect is R times C. R is the resistance of the pot and C is the capacitance. You can use R in ohms and C in farads, or R in megohms and C in microfarads. With a 1M pot and 1 µF cap, as shown in the schematic, you should get an attack time of about 1 second. With 24 100 nF caps in parallel you have 2.4 µF so that would give a maximum attack time of about 2.4 seconds, which is just what you’re reporting.
Typical acoustic instruments have attack times of maybe tens of milliseconds. If you really want attack times greater than 2 seconds you need fairly big capacitors, e.g. 10 µF with a 1 M pot for maximum attack times ~ 10 seconds.
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Thanks for the theory.
I’ll try the trick with two electrolytic back to back
I am very enthusiastic about the discussion of cases and finishes. I’ve considered General Finishes milk paint then polyurethane. It seems to work with guitar bodies so I expect it to work with modulars.
-Fumu / Esopus
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Id love to see how it turns out.
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So I received my AS3340 PCB and soldered everything on it.
Measure voltage before plugging ICs in.
Put ICs in, hook up tto speaker and a short blip and than nothing.
Turned out my speakers have a defective cable.
Connected other speaker, worked.
Then I took my Keysstep and started tuning.
After 5 minutes I gave up.
Then I looked at the schematic if I did an error and indeed I did.
I connected the 5k6 to the 24k instead of connecting it to pin 3 of the AS3340
So the bad news is that I have 5 “defective” PCBs.
Good news is that it’s easy to fix, I’ll desolder 5k6 and solder it directly on the 10k pot which has exposed legs.
And I’m actually pretty happy that my first ever PCB only has a small error.
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Great job for a first go. Will you be correcting the gerbers?
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Thanks.
Yes, already done
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