Stereo filter board for Shruthi/Phoenix - first soundexamples out

Hi, i plan to build a true stereo filterboard for Shruthi/Phoenix.

Ok we have some filterboards … but not in stereo …
The Plan . Two filter one for R one for L . Adjustable with CV 1 and CV 2.
The schematics is ready , today i have made a first test how i can add CV1/2 and the frequency control.
It is possible to set the L channel to LFO1 and the R channel also to LFO 1 but with 180 -degree so that it gives a nice stereo modulation .
With the mod Matrix it is also possible to control Filter R with ADSR 1 and Filter L with ADSR 2.
More comes soon . Next i will build the first prototype and post some pictures and the schematics .



Sounds cool Andre!

Can you add a Pan/Balance destination to the mod-matrix? LFO-controlled panning was one of the nice features of my old Waldorf Miniworks standalone filter.


What happened to the eurorack version of your Shruthi Steiner-Parker filter? I still want one, and so would lots of other people I suspect.

Hi Benne,
seems that it is too special. in spite it sounds very interesting i have less response.
@Toneburst, yes this is the trick , you can modulate the Filter R in the mod matrix with the LFO1
and Filter L also with LFO1 but -180 degree. So it should give nice panning . Also you can select all sources and send it to CV 1 and CV2 . CV1 is filter cut R , CV2 is filter cut L . On the Picture you see at first the double LOG converter for Filter L and filter R.
Next more and the first schematics. BTW i will also improve the VCA . I have here a new circut and it seems that it works better than the original SMR4 one.
Let you surprise , i also let me surprise how it sounds .



Sounds like a great plan!

Nice! I’me sure there will also be interest in de euro filter once it’s ready.
So there will also be 2 VCA’s? and also separately controllable?

Hi, 2 vca, yes,separately controllable, no. This because i have only two cv controls.
But i think 2 filter controllable is more than ok.
We will see , ahh… hear.

Andre, I don’t think you can judge to potential market for a eurorack filter from the lack of interest in a Shruthi filter board - the eurorack market is much bigger. However, so is the competition.

Will it also have a stereo input? This will be very interesting!

My experience with Eurorack: if you make it into a DIY kit, they will sell.

I’m also sure eurorack filters will sell.

agreed. But, if there is any doubt in sales, offering kits is a great way to start. At least, it was for me. The 1st module is a scary move.

Hi Guys , i know it with the eurorack, but we have a lot projects in the pipeline before…
The stereo filter is for me to warm up. I build it just for fun because i will hear how it sounds.
I have made the schematics now since a jear . BTW , it is the improoved degenerator filter board . Yes and than the degenerator. It is a little bit silent with the degenerator , but , we work hard on it . The software is round about 80…85 % ready. And Rolf had become gray hairs…This is the next Big project . Rolf and i phone nearly every day to discuss the schematics and the software functions . and AFTER this, in plan is a euro rack sampler. We have now all the C++ procedures ( the same like in the degenerator ) and we can use the same CPU ( maybe a better one ).
This comes hopefully in the beginning of next year. And than we start with some other eurorack modules.
Than there are some small things like a stereo filter BOX and i think since 2 years about a DIY vocoder. Oh God give me more time…
short form .
1:) stereo Filter for Shruthi------ for christmas-----
2:) degenerator
3:) eurorack Sampler
4:) maybe a stereo filter box , based in the P4 filter, 2 LFO’s, Ring, soft dist … Rack and standalone.
5:) and if i feel mad enough a 12 band vocoder …
After the Degenerator we will design all modules in this way that you can use it as a eurorack module or standalone .



I better start saving up some money. Or should I just put you on a retainer Andre and start sending you a monthly amount?

My hair is not gray. It’s a little dusty in my apartment because I have no time for clean up :wink:

Best Rolf

hihihi , it is a kind of white dust .

Oh wow lots of interesting things happening.

Vocoder? MFOS made one, too. Did you take a look, Andre? I don’t think the sound is worth the effort… My personal opinion…

To reiterate shiftr’s question: will the stereo phoenix have stereo inputs?
I’m still definitely in for number 4!