[tINY]

Originally Posted by SAC

And these frequency and spatial errors are worse than if you had just one transducer or several tightly packed drivers!

OK - I think I understand you now. Above is the only part I disagree with.

In the original drawing from Germany, the 4 woofers on the front wall are shown to be about 1/4 of the way in from the ceiling/floor and side walls. If you only consider frequencies below where the distance between the drivers is 1/2 wavelength, then most of the room sees no destructive interference from the multiple drivers (at least until the wavefront bounces off the back wall). Frequencies higher than that (where 1/2 wavelengths are less than the driver spacing) will not be coherent and you get positional frequency response variation.

If you want to put it in terms of lobes, the whole room is in a single lobe below this critical frequency.

We never did get around to trying a delay and a rear set of speakers to counteract a wavefront (slapback was bad in an auditorium at college). My suspicion is that you could only do that at low frequencies such that a coherent wavefront hit the wall. In small rooms, I think the double bass array could work reasonably well, as long as the LPF was properly chosen. But maybe you could do it at higher frequencies if you had good pattern control from horn loaded speakers.



-tINY