OK, I've finally been asked to spill some of the beans regarding this new, as-yet-unnamed, model. By now we have received a number of questions, all of which are in a similar vein:
I've seen these before, aren't they just a bipolar speaker?
Why have drivers on the back of a speaker where I can't hear them?
Why do you need 4 amplifier channels and a DSP anyway?
What are you guys up in Dwight smoking, and where can I get some?
First a little background:
Many people do not realize that the sound we hear from a speaker in a room is comprised of direct and reflected signals that come from all surfaces of the speaker, except for the bottom if they are floor-standers sitting directly on the floor.
It's an amazing sight to measure a conventional speaker in an anechoic chamber with the BACK of the cabinet pointed at the microphone and witness that there is quite a bit going on back there. The bulk of the sound does come from the front and sides of a typical speaker, but as we move higher and higher in frequency, more of that information disappears as we move around the cabinet. Low frequencies don't behave the same way as they are omnidirectional by nature. This gives us something of a discontinuity in that at higher and higher frequencies we are radiating less and less acoustic energy, or power, into the room. So why do we care? Well, simply because this issue of "most of the energy up front" tends to compress the natural sense of acoustic and depth perspective of instruments, singers, and the space they were recorded.
The idea of biploar, which as many of you know I am VERY familiar with, was to duplicate the signal coming from the front of the speaker at the back of the speaker. This signal would be in phase with the front (push-push), unlike a dipole which would be out of phase at the back (push-pull). Theoretically, you would now have an ideal radiation pattern all around the cabinet, with no reduction in mid and high frequencies. Unfortunately, there are significant issues that come with the benefits. One is that by introducing this extra energy into the room, you end up skewing the total balance. It's becomes tipped up at the top end. You also end up with some serious cancellations between the front and rear drivers which tend to wash out images and give you 10 foot wide vocalists! And because you are driving this bipolar speaker with a single amplifier, you have limited control on how different the front and back signals can be. In many cases the level of the rear section is simply reduced to try and combat these issues. We have a speaker that has a natural sense of space and depth, but with tonal and imaging issues. Great...
The solution? Come up with a way to give the speaker a perfect power response, get rid of the cancellation, and make sure the tonal balance is perfect. Easy, right? Yes, it does sound easy, but practically it's difficult to implement. You need to drive the front and back sections differently and independently. That's why we need an extra stereo amplifier for this speaker. We also need to have far more control over the acoustic response of both sections of the speaker, something impossible with conventional crossover networks on their own. 4-channel DSP to the rescue!
If you do this right, and, believe me, that takes a mountain of R&D, you can have your cake and eat it to. Exactly what we are doing and, more importantly why, will remain a secret. What we have been able to achieve is what we believe to be the first "omnidirectional" speaker, which we've codenamed LFR (Linear Field Radiator), that does not trade off neutral tonal balance and imaging precision for an artificially big sense of space. If you have listened to bipolar speakers before and haven't liked them, you need to listen to these!