Alumapro BP-12
Alumapro's latest ground-ponder takes subbass
to a new level of intensity
by Brian Smith
The BP-12 is a 12-inch aluminum cone single tuned bandpass sub system utilizing dual 4-inch ports. The box measures 15.75 x 16 x 19.75 inches overall, and has internal volumes of about .8 and 1 cubic foot for the sealed and ported sides, respectively.


This thing seems to be tuned specifically for sensory stimulation - it hits like the devil's own wrecking crew. Output in the upper octave of its range is vicious, and my nose still itches from that last Pandisc cut. Anything that's supposed to go "BOOM" does it in a big way. We did find that audiophile-quality material suffered a bit (i.e., string basses were a little mushy), but this puppy was obviously designed to rock. Neutral is not a word you'll find associated with this sub, and I don't think that was the intention. If you're looking to be heard from blocks away, check this one out. We haven't perfected the neighbor-irritation scale yet, but rest assured, this one is going to have a very high number.

Impedance measurements show a maximum 53.2 ohms
@ 94.6 Hz, and a minimum 4.4 ohms
@ 54 Hz. Average impedance measured
8 ohms. Out-of-car measurements show a slight dip in response below 100 Hz, followed by a 3 dB peak at 47 Hz before the steep roll-off we've come to expect from tuned enclosures.
In-car measurements show a 1-watt sensitivity of 95 dB at 20 Hz and a smooth, if not flat, overall response. The top trace (300 watts) shows about 3 dB of power compression and an SPL of 126.5 dB at 100 Hz.
Price & Contact: $409.95; 630-543-9112;