Compressors are great for making a track sound "different". If you really push a compressor you can get all kinds of "artifacts" such as "pumping", which means certain levels of certain sounds will go up and down, in and out of the mix in a way that gives a pumping effect, which sounds great when used properly. I love running a whole mix through a compressor and "squashing" the signal (over-compressing it), so it's all pumping and the levels are bouncing along with a lot of movement and variation. Hard to explain exactly what sounds pleasing to the ear by doing this, but to me it sounds great. On the other hand, it completely kills all the subtle dynamics of the song basically, so if you were going for quiet background noises with subtle dynamics, pushing a compressor to the limit is going to nullify that. However, I've found that I can properly mix a track that is pumping just fine and can still control some of the different sound dynamics by raising and lowering levels. There's definitely an art to running compressors in this way. But yeah, that's how I use them. Forget doing it by the book
