Is There A Big Difference Between Subwoofers From Different Manufacturers

high-level connection is genius

No, it isn't as it does nothing to clean up the mains' low end. The interference between the mains and subs makes the bottom nebulous.

I'm sure all those extra connections and wire are destroying the sound 😉

Negative comments on REL SQ or build quality do seem to be rare.

Not many have heard properly integrated low end in a home HiFi.

Far too many sub integrations lean toward MORE, not BETTER. As a composer pal once remarked in my room "EVERY other subwoofer I've heard just boomed!"

Correction, I meant ieales, this forum operates a bit differently than I am used to.

I have built quite a few crossovers and never seen the formula written as you have and looked it up, could not find it anywhere.

* the same as x ?

R the same as impedance?

Thanks,

Rick

I'm not able to respond directly to the OP's first question, but according to my experience the choice of a sub (or more than one) depends also very much on your room and its acoustics - and, of course, on the quality of the components in your stereo system (low, middle, consumer, high end). 

I assume nobody out there knows or remembers the make of the sub I use: Acustik-Lab Stella Novus (original spelled name), a Swiss made component which was very in demand in Asia in its time (and very costly, unfortunately). It allows settings in many ways, which was prior to today's DSP. (The company no longer exists.) So my favorite crossover setting  is 42 Hz...quite discreet. With DSP and today's choice of subs you may find happiness, too. 

Acoustic-Lab Stella Novus sub, 15 – 500 Hz, adjustable, w/ remote control 

@akg_ca --

Didn't see your post until after I had mine posted. You make excellent points. 

@mijostyn --

Re: driver size, I absolute agree with "The notion that larger drivers are "slower" is mythology to the max." It may (or may not) be interesting to note that the digital IMAX cinemas for a few years now have been using subs each comprising a quad array of 12" woofers (looks like (modified) Eminence LAB12's). I believe they usually have about 6 or 8 of those suckers installed in each theatre, and they're very powerful and clean sounding. Cinemas usually go with a number of ported dual 18" subs while some newer installations use 21"-loaded cabs, ported as well, but in any case it's interesting to see IMAX going the deviating route with multiple 12" woofers. Whether this is a consequence of a possible issue with lack of cone control in bigger drivers, I don't know, but in large cinema installations there'll be prodigious subs cone travel for sure.

The question is how lack of cone control in larger drivers (i.e.: 15" on up) relates to a domestic setting. A larger cone may be more difficult to control, but it also has to move less for a given output, and for cone control to be an issue you need cone travel to speak of. The cones of the 15" B&C woofers in my dual corner-loaded tapped horn subs only vibrate up to a few mm's at most at SPL's that seriously pressurizes the room; lack of control is a nonissue here, believe me. Remember the horn on the front side of the driver acts as a force multiplier, so with the combined and summed output of the backwave you have an effective air radiation about 3x that of a 15" direct radiating driver. And there are two of them, corner-loaded, hence it figures why the cones only move so very little, also explained with them having excursion minima at the tune. Bass like that doesn't force itself on you at ground level, but simply energizes the whole space around you very smoothly and effortlessly. Bass just happens as opposed to feeling delivered with effort. 

Yes, big cabs dominate the room, as my TH's would testify at 20cf. each. Corner-loaded though don't I feel it to be an issue, but seeing them out in the open they're just huge.