Wasnt aware of any such matches Mash. I am going by what is published. AV123 is within driving distance of me and they make and sell good products. You like SVS fine. I like AV123 fine. All are fine subs.
Here is the cut n paste from av123 website you mentioned.
Typical in-room response extends to 15-17Hz. Below 20Hz, the average human cannot hear so that is where the shaking really kicks in. Want to tear down your house without the help of a front end loader? Pick up two MFW-15's! The MFW-15 is not all about Home Theater explosions and aggressive impact. It certainly can handle those things with aplomb but it also handles your favorite music as well. From a timpani-driven crescendo in your favorite score to The Police's great bass line in the live version of 'Don't Stand So Close to Me' to Massive Attack's entire Mezzanine album, the MFW-15 delivers. Crushing bass? Check. Effortless presentation? Check. Sweet and subtle? Check. Gorgeous cabinet? Check. Oh, we have not told you about the cabinet yet have we?
(Image removed from quote.)
I will agree the graph is pretty useless but where is the rolloff you mentioned?
Here is a cut and paste of their posted speaker specifications.
Specifications
• System: Single driver, folded, slot port with front termination
• Driver: 15" custom woofer
• Amplifier: Customer 350 watt high efficiency design.
• Control: Easy-access top panel with gain, variable phase and crossover
• Input: High and low level in and out plus LFE in (crossover defeat).
• Frequency Response: 18-200Hz; 15-17Hz in room low end. Greater than 115dB output above 35Hz and 103dB max output at 20Hz at one meter.
• Dimensions: (H x D x W): 23.94" x 22.44" x 18.125"
• Weight: ship weight = 125 lbs each
• Price: $599 each in Satin Black. $699 each in real wood finishes. Dual sub special pricing available.
• 3 Year Warranty
I understand Rondar. In the past, there have been some good pissing matches over this kind of stuff.
Regarding the AV123 frequency curve pic and other info. What I'm saying is that they are "too close to the chest" and do "get the buyer excited" by "promoting 2 subs".
Take Svs. Click on either of the links I provided, scroll down to the frequency curve. That is what you want in a Subwoofer and is VERY hard to find (consistency throughout the used frequency range). It's why I'll recommend them above all others. While they are like AV123 (only available on line), they provide a plethora of info. Not only that, when you email them a question, the owners reply. They will NEVER fail to provide answers and I mean never. Give them the dimensions of your room, they give you best fit (usually a box and cylinder). They'll also tell you "why" they chose that sub.
Most fall into the trap of "hey, this goes down to 15hz according to the manufacturer so it is the best". That is suicide with money. Not only are frequencies of 22hz so rare, it will have such a low SPL, that it will be a "non-factor".