Just a sidebar here: I have two systems, one for stereo pleasure, it's a 2.1 system, which has adjustable low and high pass filters, as well as a sub volume level control. This system gets me subwoofer integration that sounds just right. My other system is for 5.1 music and movie pleasure, no Pre-Pro, just an OPPO-205 Player connected to an analog preamplifier, with bass managed from the OPPO. It is set to low pass at 60 Hz and the speakers set to small follow suit, high passing at 60 Hz. Additionally, the OPPO controls speaker trim and distance settings. The OPPO's sub management is less than ideal since the high pass setting is common to all speakers; yet, this system nevertheless delivers bass that sounds just right. The key to just right in both systems is adjustment of sub volume level via a Sound Pressure Level meter rather than by ear. This is the best means I have found to make subwoofer integration actually come to fruition. Adjusting sub volume by ear on music/movie audio or test tone seems to ALWAYS get exaggerated bass, just awful. Oh, one more thing, the only double bass that's meaningful to me is the double bass violin appearing behind and to the left of Diana Krall's piano in stereo CDs or 5.1 SACDs.