speakers for a large room

@topjetboy wrote: " @Duke I never had the maggies 2 feet away. I tried it today but really did not like it. As it is now, they are back to 5 feet away from the back and 2 ft away from the side."

Well I admire your quest for knowledge in trying 2 feet! Yup, it sucks. Those additional 3 feet (to bring them out to 5 feet) make a huge improvement, because of the additional time delay they impose on the arrival of the backwave.

" When I cross them to 45 degrees, the ’sweet spot’ is broader but the image is blurred."

Maggies are NOT good candidates for the extreme toe-in that I suggested. Their radiation pattern is generally too wide, and the tonal balance changes at different horizontal angles due to the side-by-side driver configuration.

" Are you using dipoles (electrostatic, maggie, etc)? "

No, I’m using what might be called an "asymmetric bi-directional" configuration. The first-arrival sound comes from a fairly directional front-firing array, then the reverberant field is augmented by an up-and-back firing array, whose output bounces off at least one wall and then off the ceiling before arriving at the listening area. This long two-bounce path mimics the path length of a dipole speaker pulled at least 5 feet out into the room, but without requiring that much distance. The SPL and spectral balance of the up-and-back firing array is user-adjustable, for adaptation to different room acoustic situations.

The Part-Time Audiophile took some good photos at a show last summer. Note the aggressive toe-in, and the up-and-back firing coaxial speaker installed in the speaker stand:

https://parttimeaudiophile.com/2019/06/17/new-gear-from-audiokinesis-and-resonessence-labs-t-h-e-sho...

Duke

nice setup. I was looking for the mentioned 'space generator'. Is that something from another dimension?

There’s a pair of Nola KO 2s for sale at Upscale Audio for $7670 ($14,000 retail) that may deliver everything you’re looking for.  Like the Maggies it’s a dipole design but with a line array of multiple dynamic midrange and tweeter drivers that helps with scale and dynamics.  As a result they play large yet retain a relatively small footprint.  Just another option, and best of luck in your search. 

"nice setup."

Thank you!

"I was looking for the mentioned ’space generator’. Is that something from another dimension?"

Yes and no. We interface the pandimensional locality field with a velocity zone, then rotate the phase such that the spacetime continuum is expanded instead of time-dilated. So space isn’t actually "generated", but our marketing department thought the name sounded cool.

Seriously, the "Space Generator" is that upwards-and-backwards firing coaxial. The madness behind the method goes something like this:

In our home audio listening rooms, there is a competition between the spatial cues on the recording (which are desirable, whether they be real or engineered) and the spatial cues of the playback room (which are undesirable). The ear/brain system can pick out the recording venue reverberation cues in the recording FROM the reflections in the playback room, even down into the noise floor, because it recognizes the harmonic patterns. And we WANT the reverberation in the recording to be presented from all around, so we don’t want the room to be overdamped. Unfortunately all too often, the playback room’s "small room signature" is stronger and therefore dominates our perception. We may we resort to aggressive absorption which can be a net improvement, but we lose much of those beneficial late-arrival reflections along the way so we never really achieve "envelopment".

Now it is the earliest in-room reflections which most strongly convey "small room signature", so THOSE are the ones we want really to minimize. We do this by using a directional front-firing array and aiming (toeing-in) to avoid early same-side-wall reflections. Then in order to effectively present the spatial cues on the recording, we add a bit of extra reverberant energy via the coaxial unit, aimed such that it takes at least 10 milliseconds longer than the direct sound to reach the listening area. This time gap in between the direct sound and the strong onset of reflections is the key.

With this set-up and a good recording, the venue cues dominate over the "small room signature" cues of the playback room. So it sounds like you are in a much bigger room... hence the name "Space Generator". Now in all fairness your ear/brain system is coming up with its "best guess" based on a poverty of cues, but this is still generally a significant improvement over conventional speakers. The tonality doesn’t change when you toggle the space generator off and on, but the spatial "feel" does. (The only time we have heard some detriment is when the Space Generators are turned up too loud, and then clarity starts to be degraded. So the "sweet spot" is just before that happens.)

That being said, you can accomplish essentially the same thing by pulling your Maggies five feet out into the room, like you’ve been doing. We’re able to fine-tune it a bit more to the specific room acoustic situation by having controls on the Space Generator section... for instance, we’ve found that the "optimum" relative loudness level of the Space Generator section is not as loud as the backwave of a dipole normally is.   The math that I use indicates your Maggies may sound even better about 7 or 8 feet out into the room, but that may not be practical. 

(The same psychoacoustic principles apply in concert halls. In locations where the ear can differentiate between the direct sound and the reverberant sound the listener experiences both clarity and envelopment at the same time, and these are the really good seats. Credit to David Griesinger for this insight.)

Hmmm. Maybe my first explanation made more sense!

Duke