Sure. In fact, this is exactly what I do. Simply set the RCS 2.0 to unity gain....and let your preamp control volume. There something to be said for doing it this way. Digital volume controls lead to some loss of resolution at low volume because they control volume by dropping bits. Does your Audio Aero control volume digitally or in the analog domain? I'm moving off topic here. Bottom line is that you certainly can use the TacT for room correction only.
harry
harry