Postfader aux send   

With a postfade aux send, the signal is sent to the aux send master in proportion to the level of the input fader.  This is the most common way to send a signal to an external processor such as a reverb.  As the signal is sent to the master output, it also appears in the reverb field. As the signal fades, it will also fade in the reverb. Although not as flexible as prefade sends, postfade sends allow the user to maintain a consistent relationship between dry (original) and wet (processed) signals and it is ideal for mixing: no aux send knobs to fade up and down as well.