Installation
Without a manual, I called up the head honchos at Critical Mass, Claudio Laraia and Wayde Alfarone to get box requirements. After answering a few questions, such as "How much power are you using?" and "What type of vehicle is being fit into?" they recommended a 1.35ft3 enclosure with a light amount of loose polyester fill. With no time to waste, I ran to the garage and sliced and diced a 3/4" sheet of MDF to produce a fitting enclosure, complete with additional bracing.
Then, I hit small speed bump--determining the mounting hole size for this sub required some mathematics as there are no cut dimensions to be found (a nice thing to include in a manual). This sub also does not fit standard 12" mounting dimensions either, requiring a hole diameter of approximately 11.68". Its dimensions are closer to a 13" woofer than a 12".
With the box done and UL12 mounted, I headed out to my 1999 Toyota 4Runner. I placed the sub in the rear compartment with the woofer facing the right rear corner of the vehicle. To power this sub, I needed something big, so I wired up a Zapco C2K9.0XD I had lying around (SPL measurements were taken by Eric Holdaway in a Ford F-350 Super Cab using the same amplifier). We tested this exact amplifier at just over 2,100 watts (February 2002), so it should be plenty powerful enough for this rated 2,000-watt RMS sub (max power is 5,000 watts!). However, I don't think I ever approached that output level during my listening tests--as Vance always reminds us, practice safe sound.
Adjusting the crossover for this sub was easier than most. It seemed to blend right into the midbass with little adjustment. The gain was set accordingly and the time I had long been waiting for was a CD insert away.
Listening
Instrumental
Chesky Records "Bass Resonance"
This solo standup bass was recorded in the middle of a large studio, mic'ed 3' from the instrument. According to the voice introducing this track, its design purpose was specifically for testing the accuracy of subwoofers. The basis of the song is a strong transient pluck followed by the resonance of the body of the instrument. Some woofers, when pushed to their limits, will create non-musical sounds displaying their weaknesses.
I listened to the UL12 at three volume levels to gauge any changes in the playback. At low volume the performance was no less than outstanding and every bit of resonance recreated with distinction. Pushing the volume up to a more moderate level, the unwavering detail displayed at the lower level was still accounted for, serving up great tonality and a well-rounded timbre. The transients of each pluck of the string are filtered to the midwoofer with the resonant bass routing to the subwoofer. This transition was virtually transparent with the UL12. For toppers, at no time was there localization of the UL12 subwoofer.
Another turn of the volume increased the output roughly 6-8dB for a final analysis. Along with the volume increase came a couple of notes that appeared to be slightly brash. This deficiency was minimal and, to be honest, was accompanied by some rattles in the vehicle bodywork, likely aiding to the displeasure. With disregard to the rattles, the UL12 showed virtually no weakness in this pure, distinguished and difficult track that easily illustrates flaws in a response.Score: 9/10