Detailed? Or just missing bass?

[Pim]

I also tested a fantastic REL, but I think, despite the many adjustments I made over a couple of weeks, I never got the integration that would make me keep it... and I returned it to the dealer. 
When I finally started to like the sound, the subwoofer was doing practically nothing. 
Maybe the problem is mine...

I've recently integrated my best mate's subs. These are the steps I took.

Program a 20ms delay to the speakers in the Expert

Set the subs up where they fit (next to the speakers in this case.

Set a volume that feel like it's equal with the speakers

Turn the phase until you can hear them integrate with the main speakers. Phase, to my knowledge, is just a delay. So because the mains speakers are already delayed, the subs are now 'in front'. Once you have delayed them enough to 'line up', they sound great. 

Fine tune volume from there on. 

Don't ever, and I mean EVER, use bass heavy music to tune subs. Use a simple female vocal track. Even female voices have some depth to them. Once you hear that bit of depth to the voice, that's it. Don't push it any louder.