Muff's Modules & More

akrylik

(In the following lower case letters are inputs and UPPER CASE letters are knobs.)

I often find that I need to attenuate and offset my (bipolar and other) modulation sources (e.g. lfo) like this:

Ax+B

and then I often want to mix two such attenu-offsetted cv's together like this:

E(Ax+B)+F(Cy+D)

but then the two offsets and the two mixing levels become redundant so I really just want a module that does this:

Ax+By+C

and hopefully in dual and then voila! I can chain a bunch of these together get maximal shifting/attenuating/mixing control with a minimum number of knobs.

So here is my question. Does this module exist? The A-183-2 is really close but lacks the mixing part.

VortexRanger · Posted: Thu Mar 29, 2012 8:59 am Post subject:

I'm not sure I fully understand your equation, but Synovatron's CV Tools might be close? I haven't used it but I think you could attenuvert your two signals on the first two channels, then offset with the 3rd and take the sum output.

bphenix · Posted: Thu Mar 29, 2012 9:03 am Post subject:

this may of interest: http://synovatron.blogspot.com/p/synovatron-modules.html

akrylik · Posted: Thu Mar 29, 2012 9:27 am Post subject:

Thanks guys! I did not realize it at first but the cv tools will definitely fit the bill because all the inputs are normalled to a voltage reference for generating offsets, sweet! The channels are cascaded and the cascade is interrupted when you insert a jack, double sweet!

This got me thinking that maybe other cv mixers also have their inputs normalled to a voltage reference and hence able to create offsets. Turns out the A-138c has just channel 1 normalled to vref, so you can add one offset. Again sweet!

The birds are singing again. nanners

VortexRanger · Posted: Thu Mar 29, 2012 9:36 am Post subject:

Human Koala · Posted: Thu Mar 29, 2012 9:41 am Post subject:

EDIT : I'm a little bit late d'oh!

Doepfer A138C,
first input can give an offset if empty
you have 3 input :
First one empty give C , the two other AX+BY+C

HK

akrylik · Posted: Thu Mar 29, 2012 10:18 am Post subject:

flashheart · Posted: Thu Mar 29, 2012 10:28 am Post subject:

Maths can't do complex maths like AX + BY + C, only AX + BY or AX + B hihi

VortexRanger · Posted: Thu Mar 29, 2012 10:49 am Post subject:

tommi · Posted: Thu Mar 29, 2012 11:24 am Post subject:

Also the Fonitronik Mh-01 (attenuverting mixer) can do the trick!

John Noble · Posted: Thu Mar 29, 2012 11:37 am Post subject:

Doepfer's A-138m can do Ax+By+Cz+D

The first row can be normalled to +5V, and the columns can be polarizing if necessary. I want one.

synthomaniac · Posted: Thu Mar 29, 2012 1:49 pm Post subject:

I like the way this question has been posed in maths notation applause

Thanks to Bphenix and VortexRanger for the recommendation - CV Tools can do Ax+By+Cz+D or Ax+By+C and Dy plus loads of other combinations and then smooth (slew) the output too. Here's a full list I did for the manual, sadly not in maths notation (any input can provide an offset providing it is not patched):-

Hope that helps
Tony Steventon