if i am putting sound from my scart output on my computer to the amplifier of my sound system will that affect my amplifier in any way. is it already being amplified by the computer and if so is that bad for the amplifier of my sound system?

you don`t say how much it`s pre-amped by? if it`s enough to drive a small speaker or headphones, then it`ll be too much for direct input at line level, you`ll need to use a few dropping resistors inline to compensate for this. other than that, it should work just fine

No, it won't hurt your amplifier.

If the audio output from your computer is too high (which I doubt it is), it will simply saturate the output of your amp.

overdriving the input to the slave amp will cause distortion, using a 100ohm and a 1k ohm resistor you can easily drop the signal by a factor of 10 and make it compatible.

you`ll need both resistors per channel (4 in total).

 

it`ll probably cost you more in solder and electrical tape than to buy the resistors too