Ivan Beaver wrote on Fri, 26 October 2007 06:21 |
The 2nd version of that model Tom was talking about works much better. It is 30Wx48Tx26 deep (smaller than a lab sub and easy to move and great truck pack). Output @30Hz with 2.83V input is over 102dB. Combine that with 2000watt RMS power and you have an idea that it will get VERY loud and low!
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Too bad you didn't bring it to the Prosound Shootout. Would have loved to see you there.
Did you notice how little distortion the 12Pi had? Even when pushed to extreme power levels, the distortion is down at the levels of the noise floor. Most basshorn subs have distortion that's louder than the fundamental at very low bass frequencies near horn cutoff. The 12Pi doesn't, distortion remains low at high power even at the deepest bass frequencies. I think that clearly shows the benefit of using push-pull drive.
One thing you notice right away is how most horns make a throbbing, whooshing, sometimes a thumping sound way down low. I'm not talking about the jackhammer sound of the voice coil hitting the plate, I'm talking about LF distortion. It is pure distortion, down way under the horn cutoff frequency where the fundamental is very quiet but harmonics are amplified by the horn.
The 12Pi basshorn is dead quiet when driven by signals under cutoff. When the frequency is raised into the passband, the horn comes alive.
No distortion.Most people don't run basshorns under the flare frequency. Some do. But everyone runs them down as low as possible, and the distortion reduction from push-pull drive is clearly evident in the passband, especially at the lower end. I don't think I'd ever build a basshorn with two drivers that didn't use push-pull drive. That's one of the biggest advantages of having two drivers, in my opinion.