Wake up / Put to sleep amplifier according to audio input


Got this old audio amplifier from my step parents to help boost the sound of the TV. The problem of it is that it doesn’t have a remote, and it defaults to sleep mode when plugged. I would like it to turn on and off with the TV, which would help me not getting up of the sofa 8)
It is plugged in through a (TV)jack<->RCA(Amp) and the power switch is a simple momentary switch :

My idea is to put a small arduino (I have a nano laying around) to detect sound and simulate contact on this switch (turn on when sound is detected, turn off when 5 min without sound for example) :

My questions are :

  • is that overkill using arduino ? If so, what kind of electronics would you recommend ?
  • is that feasible or am I going to encounter blocking issues (sound analysis requires too much from arduino, voltage incompatibilities, …)
  • has it been done before ? (didn’t find anything on Google but maybe I don’t have the right keywords)


Managed to drive the switch using a relay (could not find a nice way to use a transistor for this).
Now I'm having trouble detecting sound from the sound line, I only detect something when I push the volume to very high extremities, and then I only get a few mV... I don't have any kind of amplifier at hand, am I in a dead end?

Thanks for your inputs.