An inverse-attenuator

[inteificio]

Hi,

I have a problem with one part of my hifi.
I use my PC to decode DVD & play multichannel games.

The 5 channel output for this I plug straight into my nice big Rotel RB-991 & 3 amplifier (rated minimum 200w rms pch).

The problem is, although my sound card produces reasonable quality (It cost me more than the amplifier so it better do);
It produces sound at a VERY low level!

What i need is an item that could amplify the low level signal before it hits the amps, kind of like a preamp but with no selectors or volume control.

Does anyone know how to do this?

Thanks
Peter

p.s. I am a veritable ingnoramous in this world of self built electronics, so if any responces could be in crayon, with pictures, that would be appreciated!