I'd like to know what you mean. I've never heard that terminology. Learning is fun.
Well, the DL1608 could originally only tap off the signals for the aux sends from pre and post the L&R channel fader. The last update added a pre-DSP (EQ and dynamics) tap. IMO the right way to do it is to have the signal path laid out as:
Input, Preamp, HPF, Gate, Limiter, EQ, Comp, Channel Fader
with available taps at post limiter, post EQ, post comp (AKA pre-fader) and post fader. Some might want the processing order different and some mixers allow you to specify the order somewhat. Cheaper mixers (like the DL1608) often only allow you to specify the tap point per aux - the better ones allow you to specify the tap points per-channel too. You might want all your vocals pre or post EQ but the keys, bass, and kick post-comp in you monitors for instance.
