[eiouwa]

Hello.
I have a soundcard, but I don't know which model. There are four 3,5mm outputs.
My speaker amplifier is connected to the 3,5mm output which I previously used for some 20 Dollar active speakers and also headphones. Is this the right output to connect the amp to? I'm asking, cause as it can be used for headphones, too, isn't the signal already amplified there and thus it would be better to use a suitable, non-amplified output, if there is one?

 

[eiouwa]

Problem solved - I know that it's the right one.

 

[billybob_jcv]

A headphone output and a preamp output are very similar and sometimes that's the only choice you have. Yes, you might be "double-amping" the signal which can increase noise, but it's not the worst thing in the world and if your soundcard is relatively low noise it will work fine.

If you want to avoid double-amping and you don't have a true line-out on your soundcard, then you can use a USB DAC like this:
http://www.amazon.com/Behringer-UCA202-Audio-Interface/dp/B000KW2YEI/ref=sr_1_1?s=musical-instruments&ie=UTF8&qid=1389632965&sr=1-1&keywords=behringer+uca202

Or any other USB DAC. However, in this situation, the DAC will *be* your soundcard, and you will have to tell Windows which soundcard you want it to use.