"The process by where a signal level is increased. Depending upon the systems design, the expander operates by increasing the gain of a signal as its level falls or by increasing the gain as the level rises.
When using an expander that operates on the former and more commonly encountered system, as the signal level falls below the expansion threshold, the gain is proportionately decreased (according to the expansion ratio) in such a way that low level signals are reduced."
From "Modern Recording Techniques" Huber und Runstein, fourth edition.
This is similar to the way DBX noise reduction works, and an expander can be used in this way, though not as efficiently. It will remove whatever you have set at the threshold level.
Set too high and you will take out reverb and delay tails, sustained notes, etc.
Upward compression is called expansion. "The process by where
Upward compression is called expansion.
"The process by where a signal level is increased. Depending upon the systems design, the expander operates by increasing the gain of a signal as its level falls or by increasing the gain as the level rises.
When using an expander that operates on the former and more commonly encountered system, as the signal level falls below the expansion threshold, the gain is proportionately decreased (according to the expansion ratio) in such a way that low level signals are reduced."
From "Modern Recording Techniques" Huber und Runstein, fourth edition.
This is similar to the way DBX noise reduction works, and an expander can be used in this way, though not as efficiently. It will remove whatever you have set at the threshold level.
Set too high and you will take out reverb and delay tails, sustained notes, etc.
Hope that helps.