The compression range and palette of sounds that can be found with the 501 is virtually infinite. With its Feed-Forward and Feed-Back Control, you have two completely different sounding compressors. If you need aggressive transient shaping for drums and percussion instruments, just dial in your desired amount of compression with Feed-Forward mode. Or use Feedback mode for a seriously round and warm response on things like drum overheads, bass and vocals. You can dial in the perfect amount of glue for anything you want. It is a sweetly enhancing sound, that is well suited for all-duty workhorse compression.