From ML website:
"True dipole speakers, such as electrostatic panels, have long been noted for their near-ideal radiation patterns. They send very little sound to the sides, thereby minimizing side-wall reflections with short arrival times that tend to interfere with perception of the direct sound. Their strong rear radiation, however, produces a generous amount of ambience-enriching later-arriving reflections off the wall behind them."
Care to comment?
JonFo, my guess is that most of the acoustic energy these traps absorb is below 100Hz, where the panel dispersion pattern is irrelevant.
Don't your measurements support this guess?
While it is true that dipoles radiate very little mid and high-frequency laterally, due to their equal volume rear radiation pattern, that rear wave will travel, hit the wall, ricochet at an angle (assuming you have them toed in a bit), bounce off the side wall, then mix it up in the room.
It’s the control of the rear wave that is the primary reason why I covered the forward 2/3 rds of the room length along the side wall to the front wall. Those reflections are pretty well damped now
So while many people want the added ‘ambiance’ the rear wave reflections can provide, they are slightly less accurate (comb filtering is obvious) and they do not image as well for multichannel.
And since I do 98% of my listening in multichannel (thanks to a great center), I rather prefer the more focused results that dampening the rear wave and associated side wall reflections provide.
As JohnA correctly notes, much of the reason for traps along side walls is not just first reflection or high-frequency management but generalized bass trapping. And since frequencies below 300Hz are increasingly omnidirectional, the traps need to go where the room modes are. And unfortunately, when it comes to low-frequencies, they appear all over the place.
The system is still plenty bright, but it has an extra layer of articulation that was not there before. Some of that is the new preamp and Audyssey EQ, some of it is the new treatments.
The room is not quite done acoustically, as I have yet to hang about 8 or so traps from the ceiling.
That will further manage certain modes and get me as close as I think is realistic to making this room the best it can be.
