Matriarch Noise mix input inverted

Mother-32, DFAM, Subharmonicon, Grandmother, Matriarch
Post Reply
chocolatyshatner
Posts: 6
Joined: Tue Jul 14, 2020 8:04 pm

Matriarch Noise mix input inverted

Post by chocolatyshatner » Tue Jul 14, 2020 8:30 pm

Just noticed that the noise input is inverted from the rest of the mixer inputs when trying the "Dirty Duo" patch from the patchbook. Haven't noticed any mention of this in the manual or reviews. Doesn't matter TOO much, I was getting more resonance rather than filter drive, suggesting negative feedback. Just had to invert it. :idea:

User avatar
bichuelo
Posts: 862
Joined: Fri Jan 22, 2010 5:25 pm
Location: Bogotá, Colombia
Contact:

Re: Matriarch Noise mix input inverted

Post by bichuelo » Thu Oct 08, 2020 9:51 pm

What do you mean? I just tried feeding a signal to both Noise In and Osc 1 In and the results were the same
http://audiotecna.info
T-III, Voyager, VX-351, Slim Phatty, Model D, Sub Phatty, Subsequent 37, Minitaur, all moogerfoogers and minifoogers, EW+, Theremini, Model 15, Filtatron, Animoog, Model D App, iOS 11 Mother-32, DFAM, Werkstatt, Win7, High Sierra

chocolatyshatner
Posts: 6
Joined: Tue Jul 14, 2020 8:04 pm

Re: Matriarch Noise mix input inverted

Post by chocolatyshatner » Sat Oct 10, 2020 9:05 pm

Plug a saw wave into the noise mix in, and it will turn into a ramp wave at the output of the mixer. The signal is flipped 180 degrees. So if you plug osc 1 into the noise mix and turn up osc 1 mix to the same level, they'll cancel each other out.

Having an inverted mixer input can be handy for creating voltage controlled filter resonance. Take your filter output, put it through a vca, put that through an inverter, and then mix back into the filter. As the amplitude level increases of the inverted filter fed-back into itself, the resonance will increase. The noise input is already inverted, so you can skip that step. The gain of the noise in mine seems to be slightly different than the osc inputs, though.

chocolatyshatner
Posts: 6
Joined: Tue Jul 14, 2020 8:04 pm

Re: Matriarch Noise mix input inverted

Post by chocolatyshatner » Sat Oct 10, 2020 9:53 pm

If you feed the the filter back on itself without inverting, it will distort and become unstable. This is a classic Minimoog trick. Patch the MM headphone output into the external input. There are a lot of ways the accomplish filter feedback with the Matriarch, both inverted and non-inverted. I figured out a killer 8-pole lowpass(ish) patch with minimal bass freq loss at high resonance. Explore!

User avatar
bichuelo
Posts: 862
Joined: Fri Jan 22, 2010 5:25 pm
Location: Bogotá, Colombia
Contact:

Re: Matriarch Noise mix input inverted

Post by bichuelo » Sat Oct 17, 2020 10:48 pm

You are right! It is great and I have been able to recreate the classic Minimoog PWM which is done by combining an inverted sawtooth with a sawtooth

Now I am, indeed, experimenting with it and making some wild new patches. Thank you so much!
http://audiotecna.info
T-III, Voyager, VX-351, Slim Phatty, Model D, Sub Phatty, Subsequent 37, Minitaur, all moogerfoogers and minifoogers, EW+, Theremini, Model 15, Filtatron, Animoog, Model D App, iOS 11 Mother-32, DFAM, Werkstatt, Win7, High Sierra

sdwillingham
Posts: 56
Joined: Wed Feb 16, 2022 1:42 pm

Re: Matriarch Noise mix input inverted

Post by sdwillingham » Fri Apr 08, 2022 10:09 pm

Bump - an old post, but it’s a very cool tip

DaveInSanFran
Posts: 2
Joined: Wed Dec 28, 2016 4:10 pm

Re: Matriarch Noise mix input inverted

Post by DaveInSanFran » Sat Jun 11, 2022 4:09 pm

I just ran into this inverted noise input by accident, and dropped in to see if anyone else had seen this. I'm glad I'm not alone, and it seems to be either by design or a happy accident! I could see this being a useful way to tweak signal shape. It's not quite a wave folder, but I might try to add some more complex PWM this way or mix a saw and ramp.

Post Reply