ModularGrid Rack

I'm several hours into using my first rack (M32, Dixie, Maths, Quad VCA) and having a blast, but there is one recurring problem I haven't figured out how to solve:

I'm running a sequence on M32 and driving the Dixie from the M32 (M32 KB > Dixie 1V/OCT). Then I send output of Dixie square wave to Quad VCA IN 1, but the sound is droning because I have not created an envelope. I then use channel 1 or 4 of Maths to create an envelope which I send to CV input 1 of Quad VCA, and now I hear "notes" being played as desired.

The problem is that when the notes "stop", I still hear a very quiet droning of the Dixie square wave. I'd like to instead hear complete silence between notes. Sorry for the noob question, but if any experts could pass on their best practice for removing this low baseline of VCO droning I'd appreciate it. I have a Quadratt on the way in the mail in case that is helpful.


Hi Newvin,

It might be useful if you could provide your link with your rack that you are using regarding the above mentioned case, so it's easier to troubleshoot the problem.

Talking about troubleshooting, did you troubleshoot this, starting from the beginning and then step by step going there where you are now with your sound? What I mean is, start first just with that plain VCO, see if it behaves as you expect it should be, then do the next step, break the sound-circuit from the VCO to your output module, is it directly quiet? Then the next step, add the next module of your above descriped setup and check again: does it behave the way you expected it? Then abruptly break the circuit and see if it's directly quiet. Keep repeating this with adding step by step the modules you are using till you found the problem, and then solve that where you found it :-)

That might be a long road to go but it helps you in understanding exactly what's going on where on the road of sound creation, if you get my point?

Good luck with the trouble shooting and if nothing goes or helps, provide the link of your rack (and additionally perhaps a patch overview) and tell the exact setup, perhaps then it's possible to trouble shoot it for you.

Kind regards, Garfield Modular.


Thanks, GarfieldModular. I've edited the post to include my rack (although the Quadratt and Disting are not yet installed). I'll try the step by step approach you outlined tonight and post back if I still can't figure it out. Thanks again!


Solution to this should be simple enough: if you're running your audio path in the patch example you give through a VCA in linear mode, this behavior is what you should expect. To eliminate the VCO leakage, try changing the VCA's response to exponential. You will need to adjust the envelope's "ballistics", but that should fix the VCO leak issue. If it persists after that, turn the VCA's CV level down and change the envelope so that it's outputting a hotter envelope signal into the CV input.


Changing the VCA's response to exponential and further fiddling with the envelope did the trick. Thanks, Lugia!


I'm going to reply late to here but something to observe.

The Maths module is capable of doing offsets. So while your VCA knob may be all the way down, you may be leaking an offset into it that prevents it from fully closing.

On your Maths output, be sure to use the direct-out from channel #1 or channel #4 and not the mixer out. Use the output below the black box with the LED in it and not the outputs labeled "1" or "4" or "sum" etc. Then you'll be sure that your VCA fully closes.

This might not be the case... but it might be.


I'm going to reply late to here but something to observe.

The Maths module is capable of doing offsets. So while your VCA knob may be all the way down, you may be leaking an offset into it that prevents it from fully closing.

On your Maths output, be sure to use the direct-out from channel #1 or channel #4 and not the mixer out. Use the output below the black box with the LED in it and not the outputs labeled "1" or "4" or "sum" etc. Then you'll be sure that your VCA fully closes.

This might not be the case... but it might be.