When a driver is driven to extreme levels it can "compress" meaning it limits its own output by no longer responding to dynamics, having zero to do with recorded compression which is simply limiting extremes to squish loudness dynamics generally for higher overall volume...also, I don't care what REL publishes on their website regarding which mains work best with RELs (my main speakers use a "D'Appolito" array with a tweeter surrounded with equal output magnesium/aluminum woofers that are 3.75" with very large magnets in a tuned and ported column…surprisingly good bass within limits…flat to 50 hz, and rated to maybe 38hz which is somewhat misleading) as they have no idea what speakers you're going to use. I've always thought REL's use of "sub-bass" as opposed to subwoofer is silly as all you need to know is what they're doing…taking the speaker signal and filtering out the high frequencies…if you have small monitors that deliver bass to 60hz or 80hz or something, you adjust the REL to that frequency and that's it. The "not traditional" part of their hype is just not an actual thing.