directional speakers

from their site (emphasis by me):

**BACCH-ORC is the most advanced room correction technology today. Unlike any other commercially available room correction system, BACCH-ORC relies on quick in-ear (binaural) acoustic measurements, millimeter-resolution head tracking, and cutting-edge algorithms derived from years of psychoacoustic research, to produce and apply individualized optimal room correction (ORC) FILTERS: that elevate any stereo loudspeaker playback system to its ultimate level of transparency".

"BACCH-dSP is a 3D audio powerhouse application for mixing and rendering 3D binaural audio over loudspeakers and headphones.

At the heart of BACCH-dSP is BACCH® 3D Sound, a proprietary technology developed at Princeton University that allows the listener to experience stunning virtual reality 3D imaging using only two loudspeakers."

the in-ear microphones are : "used to generate personalized digital filters for BACCH® 3D Sound". (from those speakers, in that space, at the in-ear microphone's specific location.

.......................................................

Without reading about Theoretica, I presume, by OP's statement, that NARROW DISPERTION speakers are recommended i.e. narrow is best for the in-ear microphones reception NEEDED to produce the filters to create Individualized optimized room correction.

Playback via those filters want to be reproduced by the same narrow dispertion speakers.

This is definitely designed for 1 person, centered, keeping their head/ears where they were when the in-ear microphones received the in-room signal to create the filter for that specific room.

Audio Presentation: 2D Stereo; 5.1 Directional; 3D Enveloping

Live sound is generally ‘front stage based’ (except ‘surround theater’ like Cats), presenting 2D directionality (varying greatly with seat location). Conveying the sense of a particular space, but almost never experienced as surround sound.

I listen to ‘Front Stage Based’ 2D (live and recorded/reproduced). Quality equipment and speakers for fidelity. Two Speakers to provide Stereo Imaging. (great Mono fidelity already existed). The Stereo Imaging is greatly affected by the Space the Speakers are in.

Bacch4MAC (3D from 2D). Nyet, a blunt no from me. I lived thru the era of unsuccessful ’enveloping sound’ attempts, Quad etc.

I have never liked or wanted ’stereo everywhere from 2 speakers’, like Bose and others attempt, and not a big fan of attempts of 3D from 2D, like Bacch4MAC is.

It should be noted: 3D Immersion from 2D is different than Dolby 5.1 ‘directional sound’ (developed for Video).

Video’s Sound: I used to grab the speaker wires out of old CRTs, hook up better speakers, realizing the audio signal was far better than what we heard from the dinky speakers within. I was thinking about improved fidelity, not directionality

Dolby 5.1 is ‘improved front imaging’ via center speaker along with better front speakers spaced widely apart: combined with directional effects of specific sounds, placed here or there by programming, to be produced by separate additional directional speakers, for often unseen sources i.e. helicopter from rear left …. The ‘.1’ adding a sub-woofer for a Dinosaur Stomp. Dolby is enhanced directionality, not 3D immersion. (excepting battle scenes, earthquakes, ... still created by specific programming for INDIVIDUAL directional speakers, not 2. Individual Room Correction is adjusted by specific locations of 5 speakers and 1 sub, volume matched by ear or automatically volume matched by ’In-AVR’ signals and microphone provided. Those adjustments are based on and re-produced from/to the center listening position: 1 person, dead center.

‘Sound Bars’ attempt, like Dolby 5.1 to produce improved directionality (not 3D immersion) via ‘processing tricks combined with special drivers within.’

Note: omitting a center channel speaker while listening to 5.1 totally eliminates the sounds specifically programmed for the center speaker, i.e. most dialog compromised). No Center Channel Speaker: 5.1 content: Changing the AVR to 2 Channel Stereo very often improves the primary sound as center programmed sounds are added equally to both FL and FR

Now, I watch a lot of Video on my small Dolby 5.1 Home Theater.

VIDEO: I concentrate on Improved Front Imaging: 2 or 3 persons sitting on a couch: (3 persons: the Majority or 2 persons the Entire audience off-center.

Or, 1 person, i.e. proximity to an end table). the entire audience off-center, Important for both front 2D Imaging (stereo: no center or rear speaker/content) and the improved front 2D of Dolby 5.1. 2.1 simply adds a subwoofer to 2D Stereo. .

My Vintage DBX 100 speakers, are designed specifically to create a wide front stereo image. (I call the DBX 100 solution ‘cross toe-in’). Aim the Left Speaker toward the right side/Aim the right speaker to the left side. Stereo Imaging is widened based on: relatively equal volume l/c/r via opposite side increased directionality combined with volume from near side proximity. DBX 100’s have 3 tweeters (front/side/rear) to solve highs that have too narrow dispersion to work via ‘cross toe-in’.

Pseudo 5.1 (created from recordings that were not specifically made for 5.1) very often sounds better when the AVR is changed to 2 Channel Stereo. Often selecting ‘direct’ changes Pseudo 5.1 to 2 channel. I find much content is Pseudo Surround.

ATC is not directional.  They do have very small waveguides but it's a very small mid and they are very wide dispersion.  They are very much set and forget, not varying a lot by location.

@jon_5912 Thanks for the heads-up on ATC directionality.  I will, of course, take advantage of any opportunity to hear them as they have a great reputation but they are probably not ideal for my application.

Regards.

ATC is not directional. They do have very small waveguides but it’s a very small mid and they are very wide dispersion. They are very much set and forget, not varying a lot by location.

My comment was based on the specs for those mids with those waveguides. I stand by that statement.

That's not to say they don't have excellent off-axis imaging.