| There are two kinds....Upward and downward:
Upward (not as common) increases the level of signals that exceed the threshold. Applications might be a mastering engineer making an overcompressed mix more lively.
Downward (much more common) decreases the level of signals that fall below the threshold...like a gate, except that the expander lets you leave the gate open by a fixed amount. So say you have a snare which you want to gate, and in order to prevent hat spill from causing problems you need to gate quite quickly off the back of the snare....and say that sounds un-natural...you could use the expander to close the signal off by only 6 db or something so that it solves you problem without killing the snare. There are loads of possible uses of course but generally I find that when a gate is too aggressive I try to use the expander/gate idea.
J |