How to Hear Compression
It can be quite hard to hear compression with an untrained ear. Remember, you want to reduce dynamics. So if you want to hear the compression, listen to an uncompressed signal with a lot of dynamics first. Zoom in on two notes or words, with lots of volume difference. One note is low in volume and the other is high. Then, with compression on, listen closely to the two notes. They should have less volume difference now. This is what compression sounds like.