yeah thats bas amp I have. It has this compressor thing on it and i dont know exactly wat it even does... when i truen the knob up it just getts louder... does anybody know what there meant for and what exactly they do?

def'n compression: the highest and lowest points of the sound wave are "limited", boosting the volume of softer picked notes, while capping the louder ones, giving a more even level of volume.

Yeah... compressors control the dynamic range of signals.
That is to say that some notes you may pick hard and others soft. If you utilize a compressor, your louder notes will have gain reduction, making your dynamic range more even. ... in a nutshell.

You should read up on it.
Peace.