Minimal mixers


Mixer introductions from Doepfer:

Found via


I wonder if making a small case with a Euro mixer might work for line levels as well… it probably will I guess.


Yeah, it just might need extra gain since the euro mixer’s pots/controls will likely be optimized for the hot euro levels.


I’ve been using the same Behringer mixer (a 1604MX) on and off since 2002:

Not very ‘mini’ by today’s standards (18" on the longest axis, though that was considered ‘mini’ back then, and it’s only slightly larger than modern Mackies). Also came with ‘ears’ to mount in a rack, if needed (never took these out of the box).

Was actually about to sell this on eBay last month, but after shopping around for modern equivalents couldn’t find much better at a price I wanted to pay, decided to keep what I had.

(These threads could be dangerous to the wallet…)


super interesting stuff, thanks! it’s incredible what you can do with just some soundloops and a bunch of faders under your fingers! I remember when I was younger I was listening to Squarepusher’s records and wondering “how the heck is he doing the arrangments? that’s really crazy”, and then, years later I saw a studio video and here he is, mangling with a 4 track, playing with faders!


I wonder why they split the mixer + outputs into separate modules? At first I thought it was so you could chain more mixers together and use the same output but it doesn’t seem like you can.


@marcus_fischer I think I read on their website it’s so you can place them on two separate rows if you want to.


I believe you can chain more mixers together, on the page for the A-138p, which is the non voltage-controlled version, it states, “A-138o is the output module that can be combined with one or more A-138p.” The page for the A-135-4A also mentions how you can have both a voltage controlled and non-voltage controlled mixer module connected to the same A-138o.


that’s cool.


Must say I just love this thread, inspiring. I was thinking about building a small mixer and I’ve been looking at the CGS-pcbs. This one for example:

Cheep, small and easy to house in a small case. There are also PCB:s for DC-mixers, matrix-mixers and more.



Lovely. Rens Heijnis makes the most wonderful things.

Do you have a picture of the back?


The choice of having a mono Send and return seems limiting in my opinion.


I understand the need for a set of standards but it doesn’t seem that outlandish for manufacturers to offer stereo jacks on certain sound processing modules to save HP and some cost. Worst case: you use a splitter cable or simply use regular 2-conductor cables for mono operation.


I understand the budgeting factor, however I think a splitter cable would not work in this case if you are feeding 2 channels of the mixer with a stereo source (where L and R are not identical).


Could you not use splitters on both inputs and outputs in that case? No real debate here from me, just thinking out loud.


I feel you and I appreciate you chiming in.
If I have a stereo signal that I want to feed (SEND) to a stereo processor, I will need two channels (Left and Right) to go into it to preserve the stereo image.
Using a splitter on a mono signal, I m going to have 2 copies of the same signal .

That is if I have understood what you are saying correctly, of course.


I had a silly idea for a minimal panning mixer: an arbitrary number of input jacks representing different fixed pan positions from left to right, mixed down to two output jacks. Kind of like the left/right/center jacks in the output section of Isms, only more so.

Here’s what it could look like as a 1U Eurorack module, with 9 input and 2 output jacks:

Plug a signal into the leftmost jack to pan it 100% left, the next one over for 75% left, and so on, all the way to 100% right at the rightmost input jack.

Does this exist?

(Also, this is my first post here, but I’ve been reading this forum for a while. I like the vibe of the place. Hi.)

Prototyping Nearness, a minimal panning mixer module

Further thoughts:

  1. I like how this forces you to give each sound its own place on the pan spectrum, but you could of course also combine this with other mixers, minimal or otherwise, for more options. I don’t see a good way to dynamically pan sounds in this design, but maybe that’s okay.
  2. It should be trivial to build any pan law you like into this. Almost the entire circuit could be opamps and resistors.
  3. The input and output jacks should probably all be placed along the same axis, but other than that, the layout is pretty flexible. For instance, left and right might as well be up and down. Here’s a 7:2 variant as a 3HP 3U module:


Check this out - just a few dozen posts up. I would love to see something like this soon!