Available as an assembled Module and as a DIY project.
This Module is currently available.
Simple 3 input mono Mixer
Simple Mixer with 3 mono inputs, DC coupled.
Attenuation pot on each input and one master volume pot.
Vin Max = -10/+10 V
Vout Max = -10/+10 V
http://www.davidhaillant.com/simple-mixer-with-3-mono-inputs/
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