Disco Mixer (DIY analog) i need help

DIY STUFF
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Hello, I am in the design phase of a disco mixer and I would like the help of the community to help me in my design.

The idea is to create a mixer with 2 audio inputs to connect 2 different sources (2 computers) with RCA cables
Then faders to control the volume of source 1 and source 2 that redirect to a master output

and I would like to add effects such as the VCF MS-20 filter and an echo and DeLay to it
All analog

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the idea is to combine the 3 electrical diagrams in the same box

If you have any suggestions or links to help me I am a taker

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Here you can find the MS-20 schematic: Synth schematics--::-- MS 20 Filter
And stripboard layout: STUFF - LOOK MUM NO COMPUTER

And here is a schematic for an PT2399-based delay effect: https://static1.squarespace.com/static/5912db7ee6f2e1435dbab4fd/t/5ebd2841aba44056aac5587d/1589454918420/2399+SIMPLE.png
And stripboard layout: STUFF - LOOK MUM NO COMPUTER

You also need a mixer. This should be very simple using an inverting opamp, like described here: operational amplifier - Audio summing mixer- inverting or non inverting output? - Electrical Engineering Stack Exchange

The main question remaining will be your power-supply. Most people here do (eurorack) modular, meaning that we work with +12V / -12V power supplies like this one at frequency central. The choice of powersupply will affect the circuits and mostly the opamps you can use (TL07x is very popular here but requires +/-12V). I think you could power this whole setup as well using a simple 12V DC wallwart and use different lower-voltage opamps like an LM358 or something but I’m not 100% sure about how the MS20 filter will behave. You might want to look into filter designs that are built for low-voltage.

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The Xim circuit I used in my Kross module can work as a fader.

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This should give you some clues.

Also remember to use “A” LOG audio taper pots as it should give a more linear control than a “B” Liner taper pot.

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