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Hello, my vision is to create a 32x32 digitally controllable audio matrix. I already created a very basic functional concept based on the AD75019. But the IC in fact doesn't matter for now as it's still exchangable in my plans. Because I already own 4 AD75019 i've choosen them to create my first basic schematic. As I am only a software engineer with some basic knowledge in electronics I wanted you to have a look over this and tell me if its complete bullshit or perhaps ( I hope so ) a good base to start. As I read at http://www.midibox.org/dokuwiki/doku.php?id=midibox_audiomatrix I think the biggest problems which can occur is the mighty crosstalk problem (where the MT8816 should fit better than the AD75019) and possible gain problems when routing 1:n or n:1 . I read that even n:1 would make bigger problems than 1:n . If I understood it right, when making 1:n, it would solve the problems if I just add some buffer opamps after the matrix outputs. When I wanted n:1 I need something like a mixer style schematic running through the matrix IC. This would mean I have to add some resistors before the input of the matrix ic. In common to the 1:n option I also have to add an buffer opamp at the outputs of the matrix IC. To be able to chain multiple matrix ICs I also added some buffers before the inputs to be able to distribute the incoming signals to multiple ICs. Additional to that I added resistors and a final output buffer stage to merge the outputs of multiple matrix ICs. I don't know what would happen when making n:m connections. Should this be prohibited or is it possible without side effects ? Is this a reasonable idea or isn't it good to chain opamps ? Simplyfied it's nothng more than 2 opamp mixer units chained through the matrix ics. Will the audio quality suffer from this ? To keep it scalable I'd split boards into 3 types (without the controlling board and other stuff around).... 'input (distribution) stage', 'chainable matrix boards', 'output stage'. I hope you were able to understand my idea in this :) Best regards, Andreas 32x32 audio matrix 01.pdf