I'm always grateful for feedback, ellisdj, and keen to learn new things. You seem to know what you are talking about on certain topics so that's good and I appreciate it. For example, I can't wait to add room treatments very soon!
I think you are correct about the improved bass performance I am experiencing now with AW-12 and NuForce AVP-18 at the helm. It's likely got to do with a combination of several things though; dedicated and better power supplies, better DAC, meticulous volume control, better output stages and signal processing alongside the EQ, all combined. This seemingly simple processor has but one goal; pure performance over features, and it's easy to see (hear) where the effort have been made and it's paying off in my case. Antoher reason is probably that Audysseys Dynamic EQ, as excellent as it can be and as much as I was addicted to it, adds more 'oomph' to the low frequencies through it's EQ and active loudness, which this NuForce does not do and does not need to do. So at times, as great as the bass was with Denon and Audyssey it could momentarily come off a bit bloated. NuForce makes the subwoofers play in a more controlled, nuanced and agile manner, while still deep and powerful. Will be awesome to test AntiMode though and add the room treatments to further enhance things because there is room for improvement (when is there not room for improvement? hehe).
I too am learning (or being reminded of) the benefits of using a/v separates compared to integrated units, as I use to own a separates system years ago (Lexicon DC-1 processor + Musical Fidelity HT-600 amp). Also the flexibility is unmatched in a system like this. The Apex speakers certainly seem to make the most of the clean signal and raw power of the NuForce units, as their performance have risen several notches.