Good suggestion from Zd542.
Zd, he might be in a situation where he cannot correct his room - maybe "she who must be obeyed" wont let him?
I don't see why an ARC system cannot be applied to a pre/pro without room correction.
Do you have an ARC pre? Or, are you using the pre/pro as the pre for the ARC system?
If you are using an ARC pre - use the bypass or direct function on your pre/pro to simply feed the ARC pre signal to the ARC amp without the pre/pro altering the signal.
If you are using the pre/pro I bet that you can change the signal any way you want - boost the bass, extenuate the midrange, tone down the highs, etc, etc - before feeding it into the ARC amp.
FWIW.