The UL12 Thiele/Small parameters shown in the Data Chart were used to produce computer box simulations using the Leap 5 Enclosure Shop software. Box simulations were created for both sealed and vented enclosures that made sense for the parameters. For sealed box performance, I used a 1.65ft3 volume with 100% fill material (fiberglass). The 100% fill material was incorporated to provide as low a box Q (Qtc) as possible, since the UL12 has a fairly high Qts, or "Q," when measured in free-air. The vented box was what is known in engineering parlance as a Chebychev/Butterworth alignment, which turned out to be 1.8ft3 tuned to 32Hz. The LEAP 5 graph curves in Figure 4 show the SPL at 2.83V (black curves) in half-space (imagine the woofer mounted in a speaker baffle as big as a football field and that would be very close to "half-space), 2.83V in a small 154ft3 car compartment, about the size of mid-sized SUV like a Nissan Pathfinder or Toyota 4Runner (blue curves), and the SPL at a power level required to get maximum linear excursion (red curves, also half-space). The sealed box curves are solid lines and the ported enclosure curves are the dashed curves. The 2.83V results produced an F3 of about 46Hz for both box types. Increasing the simulated input voltage for the 1.65ft3 sealed box computer simulation to 150 volts increased excursion to where Bl decreased to 70% of its maximum value and pushed the SPL to a very loud 120.5dB. The 1.8ft3 vented box computer simulation required 200 simulated volts to drive the Critical Mass sub to the excursion level where Bl dropped to 70% of it nominal value and resulted in an extremely loud 124.5dB.
The UL12 is an incredible tour-de-force in high-SPL loudspeaker engineering and at 16.6lbs it will definitely impact your horsepower-to-weight ratio. For those with the ability to indulge the finer things in life, the UL12 is a sub worth considering, certainly at least from the engineer's point of view. But as knocked out as I get from such a well-executed design, it always comes down to the same bottom line. The question will always remain whether or not all that science produces a great-sounding woofer, but that's why these reviews are broken into an objective and a subjective section. So how was it Casey? --V.D.
Subjective
Critical Mass has kept me waiting... and waiting... and waiting. Finally, I got my hands on their much anticipated flagship subwoofer, the UL12. After some 18 months of seeing prototypes and even having one prematurely shipped to my office, the real deal had arrived.
Manual
This subwoofer retails for $1,999 and arrived without a manual. Really! OK, maybe I am taking this the wrong way, but for that amount of money, shouldn't a 10-page booklet in full color held by a bikini-clad girl that pops out of the box explaining the woofer in detail be included? Yes, I may have stretched that one a little too far, but while humoring myself I began thinking--if I bought... excuse me... if I could afford a sub costing two-large, would I be installing it myself? Probably not. Having the means to expend this much money on a single transducer, I think I'd indulge myself and burn up a few more greenbacks to have a trained expert install my Critical Mass sub. Don't get me wrong--I am not trying to justify the lack of information. I feel some paperwork containing warranty, contact information and a congratulatory "thank you" would be deemed proper materials to include, regardless of price.