All I can say is, my brain must be very good at filtering out the secondary delayed signal… There was no perceivable difference between with or without in your demo… I could discern all frequencies, and the stereo postitioning of each…
The video is more to explain the technical background : the audio demo is quite limitative, the effect is much more obvious in real conditions.
Do you have a separate plug-in that addresses crosstalk only, similar to the uBACCH filter?
I’m a bit frustrated by the BACCH folks, as they haven’t answered my emails and I’m questioning the pricing. Thanks
Interesting, … so if we cancel crosstalk on a Binarural recording we can expect a more dramatic “spatial” effect?
I’m not trying to usurp @Home_Audio_Fidelity 's authority here… However as was described in the beginning of the video, (for the sake of simplicity) a stereo pair of directional microphones aligned to approximate a human HRTF or a dummy-head system that is a generic HRTF model of the average human head, is the most natural way to record an acoustic performance of some sort…
This is binaural recording. Binaural recordings require headphone playback and these recordings are best presented when the hearing response of the subject and the frequency/dynamics of the headphones are measured and calibrated into the listening equation… Binaural could be played across a symmetrically aligned speaker pair, however the recorded HRTF information must be retained somehow, without interference from reflections emanating from the acoustic space in which the speaker playback occurs. This is not an easy thing to do…
Now, this is all in the context of a binaural recording… If the HRTF information is removed from the recorded signal, the L + R playback synergy of this binaural recording is skewed at best, and the image will atrophy, even if room-correction is applied, either physically through mechanical dampening/absorption or through DSP mitigations on the playback signal itself. Therefore, any DSP process will require the analysis of this recorded HRTF information and return it properly to the the acoustic space… How can this be done? At best, this reconstruction of the HRTF information in DSP, in-concert with a very precise room-correction analysis that eliminates or reduces the influence of the room reflections, so as to render these inconsequential to the playback, in which, the DSP has accounted for and calibrated the measured HRTF of the listener/subject in the acoustic space, is subsequently being delivered to the subject, in the acoustic space relative to their proximity in-between the symmetrical pair of speakers.
All well and good if everything is recorded in this manner… This is not the reality…
The majority of recordings are mixed and mastered over a pair of speakers… All tonal and dynamic decisions are made from this audition and the contextual Left + Right Channel energy that supports the phantom center-channel image is intrinsically tied to that contextual relationship… If that phantom center-channel energy is removed all contextual time/phase/frequency/dynamic/spatial relationships are destroyed and the playback is damaged. This is the primary problem with plain-vanilla headphone listening, and this damage is further exacerbated by speaker cross-talk and room reflections.
Recorded spatiality is a function of time/phase/frequency/amplitude relationships to some acoustic space in which the microphones are in proximity of the sound-source(s)… this is typically monophonic in nature… If we only had one functional ear our sense of spatiality would be destroyed until at some-point our hearing neurology and other sensory/cognitive functions compensate and we adapt to this condition. In the natural experience, these sonic relationships provide us with an interpretation of proximity, orientation, location and loudness… Simple binaural reconstruction over speakers does not provide such accurate information…. However, with a well designed DSP algorithm/function, this information can be synthesized from the information captured by a single microphone in relationship to other recorded sound-sources, in a stereo or multi-channel production.
I’ll hold it here…
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This is all very interesting @Agoldnear and your technical descriptions are impressive. Thanks to @HOME_AUDIO_Fidelity 's previous post, I was inspired to try some binaural recordings over speakers using the uBACCH filter over UPnP (RealTime) enabled.
A couple of these recordings I’m already familiar with over headphones. I can state that in my room, which is only digitally corrected in the bass, these recordings sounded as naturally spatial as I recall them sounding on headphones.
Were they truly surround sound? No. At least not in the sense that a 5.1 or plus system can sound. Nevertheless at times sounds did reach very close to me and wrap around behind me. Just not as obviously as they would using rear speakers. To my ears though, a lot of 5.1 or Atmos mixes can sound artificial, with too obvious discrete placement of sounds in the rear speakers; etc.
So this reproduction of binaural recordings via the uBACCH filter was natural and convincingly Binaural to my ears. Whether they could have been even better if all the issues @Agoldnear has mentioned could be addressed; I have no way of knowing. Subjectively though, I’m very pleased by the result.
Finally, this also means I can state that the uBACCH filter does work over UPnP with RealTime enabled in my system. When I play direct without UPnP the uBACCH window appears. It doesn’t when I play over UPnP, causing me, at first, to question if it was working. By listening though, I am confident it is working just as @Ddude003 reported.
So the only remaining problem for Audirvana is that when you disable RealTime you get the problems, I reported earlier.
It’s wonderful that Audirvana has this RealTime feature.
The “other player” I mentioned lacks that and as a consequence exhibits the same problems over UPnP as Audirvana does with RealTime, disabled. So I need to report this on their forum.
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Yes, I can generate crosstalk reduction filters with very minimal room correction (like phase only)
Thanks for your experiential insights…
Obviously, a binaural recording is not surround-sound as is typically produced for a calibrated multi-speaker array playback… However, the reproduction of those binaural recordings having conveyed a relatively equal experience to headphones, is impressive.
Just for reference and to keep it simple… Many years ago, I was a THX certified installer/calibrator of 5.1 multi-speaker arrays and video calibration at one point in my quite varied career in audio playback and recording engineering and production, and as a musician and as a student of psychoacoustics, acoustics and acoustical design, speaker system design, digital-audio and DSP and as a electronics and mechanical design engineer. …In general my experience is rather broad, with over 40 years in the field of sound engineering.
One reference for this type of psychoacoustic reproduction was brought to light by the Yamaha YSP-5100 Sound Projector which utilized multiple speaker/amp arrays under DSP control to construct a 3D sound-field. We see this today to a lesser degree in inexpensive sound-bars and in state-of-the-art and expensive sound-bars, that utilize the reflective surfaces of the listening environment, under DSP analysis of the listening position. Today Yamaha provide a psychoacoustic sound-field presentation utilizing a front-line speaker array of five (5) speakers + subwoofer under DSP control in most of their surround receivers (Virtual Cinema Front).
The beauty of modern psychoacoustic DSP as in the case of the uBAACH Labs products, is the elimination of the typical ITU surround speaker array… The drawback with a symmetrical, aligned pair of speakers, is the restricted perceptual “sweet-spot”. However, for those with multi-speaker ITU aligned arrays, the uBACCH filter design technology can accommodate a sweet-spot that accommodates multiple listener orientations within the surround array (not part of the plug-in).
It is a fantastic leap for audiophiles, that removes the listener from the tyranny of a compromised plain-vanilla stereo sound-field presentation and replaces the typical two-dimensional recording with a compelling sense of dimensionality in reproduction over a pair of speakers in a room.
Spatial Audio is the future…
The future is music recorded with one microphone, played back through two speakers at insanely loud volume… well, mine is… you can have yours…
It’s called a Victrola or Parlaphone or a music-box or a player piano or AM radio… 
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Knock yourself out with this DSP:
I was running a show last night, 500 capacity crowd in. Had piano and 9 singers… 2 microphones… sounded immense. Keeping things simple, and using modern technology, are not incompatible… Also, no way I’d get the volume require from these sources - Victrola or Parlaphone or a music-box or a player piano or AM radio… - you were just being sarcastic weren’t you, I know…
Nothing is simple in the scenario you describe…
Now that’s just being deliberately obtuse… I didn’t mention mono…
I think so… 
I found it so… As I further my experience in live sound mixing, I’m finding my lack of formal training to be an advantage… I don’t have to think outside the box, because I have no box.
In all seriousness, I know tastes change, and technology advances, and a reason for the technology will be invented, but for all the surround 7.1 4K + visuals and whatever, what appears to be happening is new ways to listen to, or watch, old shit. Creativity is not in the art any more, but in the presentaion and delivering methods.
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In the context of recorded music reproduction (My focus), watching a movie that is basically two-dimensional, unless produced to be viewed through virtualization (3D glasses/goggles, surround projected venues in concert with a 3D sound-field) … is a disjointed experience…
The creativity of a musical performance is not diminished by a dimensional representation that conveys a sense of being in proximity to the performers, etc, in an acoustic space… This is the sensory experience you are describing from being involved in the venue with the performers and audience.
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My doctor once told me that if it hurts when you do that… Don’t do that…
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This is about as good as it gets in a civilian environment… Apple Vision Pro - Apple
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