About 12pi

push pull is put in place because drivers do not have a symetrical BL curve, which is to say its motor strength excurting inwards is the not the same as excurting outwards. by inverting one of the drivers, and then flipping the phase you end up with push pull, both drivers are still displacing air in phase, except one is doing it by going backward when the other is forward, this is effect cancells out any nonlinearities the drivers motor may have.

If i recall, theres some highly entertaining bitching & slagging matches between wayne and danley on one of the other audio forums a while back ..think it was pro sound web. They certainly dont seem to like eachother.

the design is based on some matters that on paper sound like an advancement; but largely equate to being abit of a scotch mist affair resulting in even more unwieldy cabinets."

Total misinformation.

Wayne embarked on developing push-pull drivers for his horn designs largely after discussions with me on Audio Asylum in the 2003 time frame. Several of the newer models from Danley also employ push-pull drivers.

Dumax testing of some drivers in push-pull vs normal mounting of the same drivers has shown that linear x-max (as a function of BL) increased about 40%, enough for 3dB more output. Several people have commented that push-pull can play louder before objectionable break-up sounds become annoying.

The construction of the 12Pi may (in some areas) be more complex than the LAB 12, this is a function of incorporating the heatsinks on the woofers in a push-pull driver mounting scheme.

Wayne also invested considerable time and expense on trying to incorporate shorting rings in the LAB 12 woofers, only to find that push-pull driver mounting worked better at the lowest frequencies.

Wayne (and Danley too) has been a great boon to the DIY community.