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its save if i wire the inputs like that ? Answered

Hello . Im making this circuit.and i want the speaker can play 2 inputs at same time.So i put 2 resistor like this pic.This circuit works, but it's safe if i wire them like this ??
sorry for my bad English!


Not a good idea, it might work OK, it might not. You'd be much better putting an op-amp at the front to make a mixer.

i made it and it work fine, but i want to know if this circuit can harm my mp3 player or my guitar ?

It looks good to me.  I like the adder made from two 1K resistors.  Those should keep the currents into, or out of, the mp3-player, from getting too large.