Hello diyAudio Community,
i have a problem with a circuit maybe you can help me with.
I need for an exhibition an audio switch which switches 9 inputs to 1 output at a random rate. Only 1 input at the time is active.
The input is stereo via 3.5mm jack so is the output.
The problem i have is that i have a really bad crosstalk on the channels

I use an ADG409 for the switching an atmega328 as a controller
Vdd is 5v Vss is tied to GND
What can I do to remove the crosstalk / noise ?
i have a problem with a circuit maybe you can help me with.
I need for an exhibition an audio switch which switches 9 inputs to 1 output at a random rate. Only 1 input at the time is active.
The input is stereo via 3.5mm jack so is the output.
The problem i have is that i have a really bad crosstalk on the channels

I use an ADG409 for the switching an atmega328 as a controller
Vdd is 5v Vss is tied to GND
What can I do to remove the crosstalk / noise ?
Your inputs swing above and below common.
The switch chip is powered with +5V and common, and does not do a right thing when inputs go outside this range.
I am thinking that all negative swings on all inputs are breaking-over inside the switch chip.
You could R-C couple all inputs and outputs to a mid-way voltage reference.
You could re-arrange the whole power scheme centered +/- around common; this does complicate the logic interfacing.
Frankly, since the board is built and you have 12V, _I_ would get 9 electromechanical relays to do the audio, coils driven by DC power through the ADG switches (backward). It is klunky but gets the project finished quick.
The switch chip is powered with +5V and common, and does not do a right thing when inputs go outside this range.
I am thinking that all negative swings on all inputs are breaking-over inside the switch chip.
You could R-C couple all inputs and outputs to a mid-way voltage reference.
You could re-arrange the whole power scheme centered +/- around common; this does complicate the logic interfacing.
Frankly, since the board is built and you have 12V, _I_ would get 9 electromechanical relays to do the audio, coils driven by DC power through the ADG switches (backward). It is klunky but gets the project finished quick.
Thank you PRR I will re-arrange the power scheme and will try a +15 and -15 V supply. And I will add 10k resistors between audio and audio gnd. i will post the new Schematic soon.
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