I also posted over in the Speakers section for the entire system. But for you bass heads, I'll go a little deeper (pun intended) in this section.
This was an SVS Ultra with the proprietary TC Sounds TV-12 driver. The Ultra utilizes a 20-39 sized enclosure and is identical in construction to the CS+, except for the driver.
He was running off one channel of a Samson S1000 amp rated at 500 watts continuous power into 4 ohms (power calculated with RMS volatage).
He also had a Marchand Electronics SVS01 Bass Box in the loop with an adjustable SS filter, variable phase, and up to 18 dB of gain on the pre-out signal.
The Bass Box in the loop gives a very slight hum at rest - you must put your ear in the sub vents to hear it. The owner doesn't like the hum, but I could certainly live with it considering what the Marchand unit offers. It's much less than the typical transformer hum on a sub plate amp. Although I will say the BASH amp in the PCi and the PC+ line is dead quiet.
Anyway, how does it sound? Well I expected to be impressed and I was.
Subjectively, I would say the sonic accuracy of the TV-12 is just a hair better than the TC Sounds dB-12 driver in the Plus line. But they are very close.
As expected, the TV-12 driver can play louder than the dB-12 driver, and we certainly proved it. We recorded 116-117 dB peaks about 10 feet from the sub. This is a good 2-3 dB better than the dB-12 driver is good for in the same room.
1/12 octave FR sweeps yielded a flat FR from 45-17 Hz with all three ports open. He has some funny room acoustics between 45 and 100, but that's not the sub's fault.
Subjectively, I found the TV-12 driver to be slightly more "authoritative" at very high volumes than the dB-12, probably due to the fact that it's xMax is over 25mm one way and it can really effortlessly make the stretch for that last dB or so of impact.
It took everything we threw at it and chewed it up and spit it back out.
Demo material was The Haunting dts, SWII-AOTC and Atlantis. All source material was gut wrenching at reference volume.
Chapter 10 on The Haunting immediately rattled a crystal candy tray right off his HDTV. Luckily he has carpeting and it survived.
Am I ready to trade in my PC+? Not a chance. I would say the PC+ is 8/10 of an Ultra SPL-wise, and 9/10 of an Ultra subjectively sound-wise. But the PC+ is 40% less money and still rules the roost value wise.
If you've just gotta have that last one or two tenths at all costs, the Ultra certainly provides it. Overall, very, very impressive.