What's your definition of lowest bass and/or deep powerful bass? Are you talking about sub 30Hz at >95dB, high volume levels? The Avalons you have go down into the 30-40Hz region although they won't go super loud in that area.
I second what Egrady said above. If you are severely constricted about how you can position the speakers and listening area, you may never be able to obtain really deep, smooth bass. I will note that your Pass amp isn't noted for bass slam. Also, what you're missing could be effected by your turntable/arm/cartridge setup.
Could you describe what's missing on a specific recording? Compare what it sounds like to what you think it should sound like.
I second what Egrady said above. If you are severely constricted about how you can position the speakers and listening area, you may never be able to obtain really deep, smooth bass. I will note that your Pass amp isn't noted for bass slam. Also, what you're missing could be effected by your turntable/arm/cartridge setup.
Could you describe what's missing on a specific recording? Compare what it sounds like to what you think it should sound like.