What are all the ADSR's out there to build?

[nicolas3141]

My LM324 based ADSR (see above) should work on 6V, but you may need to tweak a few resistor values. You possibly should look at swapping the LM324 for a low voltage version - especially if you want to run it on 5V. LMV324 would be ideal for 5V operation, but it is only available surface mount - not sure how you feel about that. There are other options, but you will need to shop around to get something through-hole.

To run it on 6V you need to create a -3V / 0V / +3V situation with a voltage divider or whatever.

Cheers,
Nicolas

[cypher]

Hi nicolas!

Thanks very much for the very fast reply.
Well, so basicly it can work also on 5-6 V supply. The voltage divider is necessary also in the case of 5V? Is the dual voltage (for example -3,0,3V) really needed (because the chip shop also work on single voltage)?

When running from the default 9V, how big is the output of this circuit ? Is it giving 0-5V on the OUTPUT or how much (I will not want to burn out the VC AMP).

[nicolas3141]

Yep - everywhere in the circuit where it says 0V needs to be connected to a reference voltage halfway between the +ve and -ve supplies.

On 6V (ie +/-3V) supplies (if using LM324) you should tune the resistor values so that the output goes from 0V up to about 1V and then settles back to 0V. On 5V (+/-2.5V) you should tune it for slightly less than 1V.

If you need more than 1V out of it you will need to look at special low voltage capable op-amps like the LMV324 mentioned above.

Cheers,
Nicolas

[JovianPyx]

Here's my ADSR design based on a CD4069UB IC and a TL0x2 opamp (note that I used TL082, but TL072 should work too). S1 is a "punch" switch.

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[prgdeltablues]

I've been breadboarding the neat AD/AR circuit by Ian Fritz mentioned in the first page of this thread, trying out various things in the back to back diode arrangement in the feedback loop of a2 (the area of the 'truncate' switch), and thought I'd share my findings. Different diodes do have an effect on the envelope, though not very strong.

In fact, the circuit works with no diodes at all- just a wire from opamp output to - input. That gives the longest attack and decay times for any settings of the attack and decay pots. Using 1N4148's shortens the times somewhat, and using LED's makes them even shorter. Here's some screenshots from audacity showing the envelopes for various settings.

First is with min Attack and max decay. You can see using the LED's makes the decay tail off sooner. Next is with maximum attack and min decay. And finally, both Attack and Decay set to only just above minimum. You can see the LED is punchier, and hear it on the attached mp3 (this just is LP filtered white noise). (I used a 100k Attack pot and 1MEG Decay).

I'm building a hex version of this, with two of each flavour.

Peter

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[oculus]

i just made Nicolas ADSR on a vero after breadboarding it,
im loving your simple circuits i think i´ll end up building them all.

it seems to be working but i just noticed that when i had a fast attack, short decay, the sustain in zero(no sustain) and the release in zero(no release) i get this sustaining voltage but when i increase the release just a bit it goes away.

here´s a sound example -
(you might have to do a right click and save link as) http://dl.dropbox.com/u/4440248/drasl/ADSR%20release%20problem.mp3

i used 470k on the 3rd opamp on the lm354 as Fonik did and added the led driver.
im using 1m pot for attack 10k sustain 470k for decay and release
also i have a ne5532 opamp on the output for some boosting if needed and inverted Envelope output.

does anyone know what might be the problem with the release ?
i thought it might be some faulty pot so i tried also using a 1m pot on the release but it was still the same,
thanks
kind regards Fridfinnur

[frijitz]

[oculus]

i forgot to mention, the adsr is modulation the filter on korg ms10 in the sample i posted here above.

is anybody experiencing the same problem with the release ?

thanks Fridfinnur

[El Mop]

Did already someone tweak the resistors for a +12V/-12V version of Nicolas ADSR?