Posted by Wayne Parham [ 67.66.231.14 ] on October 15, 2005 at 04:59:53:
The 12π basshorn subwoofer was proven to be the most powerful subwoofer in the world at the recent Prosound Shootout. Distortion is also incredibly low, due to the push-pull arrangement. A single 12π basshorn generated 117dB at 10 meters, which is 137dB at 1 meter. Compare this with a pair of Servodrive BT-7 hornsubs at 136dB.
Only one 12π hornsub was measured, but according to models, a pair should run 143dB maximum output at one meter and a group of 4 should provide 149dB, with flat response +/-2dB from 30Hz to 125Hz. Single horn response is very good, but it is improved even more in groups, with deepest 30Hz bass output lifted to the 100Hz level.
See the chart below. Measurements were taken at 10 meters, so add 20dB to find the SPL at 1 meter. The blue line is is output with 65 volts input, roughly 1600 watts. In my recent tests of the heat exchanger, I found that the speaker can handle this level of contstant input power. Also notice the low distortion levels, which are shown by the violet line in the graph. Distortion is low across the entire range, but a particularly intersting feature is the low distortion below the horn flare frequency.
The distortion of most horns rises dramatically below cutoff, but that is not the case with the 12π basshorn subwoofer. Other basshorns make a chuffing sound when driven below cutoff. It sometimes sounds like a helicopter blade. What you hear are actually harmonics of the fundamental without the fundamental being present at all. The 12π does not suffer increased distortion at low frequencies, and is completely dead quiet deep into cutoff below 20Hz. As frequency rises to the 30Hz level and above, output rises steadily. At that point, the bass was loud enough to vibrate the entire countryside, modulating voices to the point that conversation was impossible.
[ PiSpeakers Forum ] [ Help ]