Originally Posted by BiGBADDABOOM
Guys, all of these sealed subs have EQ to set the -3dB wherever they want to. The response doesn't matter unless you have no way to change it and it doesn't work with your room. The moment the sub gets in your room it's -3dB point will change, and then throw something like an Audyssey auto-cal at it and it'll change again.
What is important is how much output you have at say 20Hz comparing one to the next. If you have those numbers, then you can discuss something that actually matters.
Getting "flat to X" is meaningless if there's not enough output at that point. Any of these guys (SVS or Emotiva) could have EQ'd their subs to have a -3dB point of 10Hz, but that would be ridiculous because you'd have no headroom to actually get usable output from the sub.
Yes, all this is true, however, the controlled test point published of a sub provides the purchaser the ability to judge its capabilities on a level playing field with other subs. Yes with room gain and audyssey it may get lower than the 25 hz @ -3db, but will it get lower than one with the same power and a controlled test of 18 hz @ -3 db? Probably not.
Its also an indication when comparing subs of what its ultimate capability will be. At some point physics will get in the way, and the manufacturers tests are a fair way of showing when that might be for their controlled test environment.