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Dr. Edgar Choueiri explains BACCH

Yeah but it’s a transient state for the signal. And it can only be judged by the final result. Without knowing and correlating the signal with input the filter was built around and the real time input of the head tracking the signal by itself is encrypted for practical purposes on analysis. The head tracking alone is going to change the results substantially in the signal if you did repeated measurements.

I do think we can rather easily separate the head-tracking component from the core crosstalk cancelling BAACH processing.
Just run transfer functions of the processing with one fixed location setting....
Whether i-BAACH, u-BAACH, headtracking...whatever...freeze any geometric focusing resets...and look at what BAACH is doing.
I would be very surprised if the core crosstalk processing varies from one focus setup/position to the next....other than accounting for geometry.


Would be quite illuminating...and moving towards hard science as opposed to anecdotal listening impressions....imo.
 
I have a question for Bacch or other xtc with HeadTracking users.
Tell me if it feels (calibrates) like the picture below.

View attachment 379960

Let's call this the listening position sweet spot.
Please excuse the rough drawing.
Imagine you're listening with your eyes closed, and head tracking compensation is involved.



View attachment 379961

And if we move like this, it should sound like that

View attachment 379962

However, head tracking and ILD correction compensate for this by making it sound like we're listening in the original sweet spot.

View attachment 379963

And it compensates for this when you turn your head.
Is this correct?
That no matter how much you close your eyes and spin around, what I'm hearing is maintained, is this right?
The boundaries of the head tracking are going to depend on the radiation patterns of the speakers being used.

The imaging itself does not shift with head movement

For front to back and side to side movement the sweet spot gets a little bit bigger but mostly and more importantly it stays completely consistent.

With conventional stereo the true “sweet spot” for all speakers is one singular head position dead center, with your head straight, zero rotation on any of the three axis. Any movement degrades the sound. How much it degrades will be speaker/room dependent but there will always be some degradation with any head position that isn’t the one ideal.

That goes away with the BACCH. The only limit on head movement within the sweet spot is horizontal rotation. You definitely can’t turn 90 degrees or full 180 degrees without losing the imaging. It holds up pretty much until your head turns past the angle of the speakers.

This freedom of movement within the sweet spot is not a trivial improvement. I did not fully realize the effort and subsequent listener fatigue that came with the need to keep your head from rotating at all with conventional stereo until I had the BACCH.

I have highly highly directional speakers. And yet with the BACCH I feel for the first time the head vice has been truly removed from high end stereo. Basic comfort while listening as well as true sonic consistency are substantially improved
 
Dude I have answered your questions over and over. You come here and make blatantly false claims that there is no science behind the BACCH, that it’s just math and theory and there has been no testing.

You are telling lies about the product in order to disparage it. How that flies on this forum I don’t know.

But I am done wasting time on you.
Man, I sincerely believe that you are intelligent and have an uncommon ability to understand and analyze.
I have never meant that a scientific approach in development has not been used. Far be it from me. As I already said, in fact I actually think BACCH is a truly remarkable piece of engineering, with a clear purpose based on established scientific principles about perception and argued by a notable mathematical model. I have no interest in discrediting it, not even moral. Just the opposite.
If that message has passed, I have expressed myself badly or have not been contextualized correctly.
I suppose I am not flawless in expressing myself, as I think anyone, and the translator does not even help. No problem in rephrase my thought as long as it is not deliberately misunderstood.
My point is essentially that on the basis of information available on website (those I've seen, but if something escapes the forum should be used to help in this regard) there doesn't seem to be a way for us potential users to extrapolate the appropriate objective data about the result in order to judge the actual value, both as regards the subjective and objective sphere of the matter, that we recognize to exist. I am clearly not saying that development tests and evidences don't exist, much less that xtc doesn't work. Just that on viewable information, for us ASR members, it shouldn't be appropriate to drawn firmly conclusions about the product and be blind/reckless supporters (nor detractors, for sure, due to the seriousness of the source).
Sure home demo could be a good thing, but it seems not available for free for the head tracking, and however it implies subjectivity problems, so some public scientific proof of result (ABX test, actual measurements...) could be desired for users to make proper evaluation. Especially since the product is not free. But obviously not strictly needed if price isn't a problem (blessed are those).
It is these kinds of reasonings that I think it's useful to do in this place. Not just talk about science, nor about subjective experience.
We all know that ASR was born precisely for this.
Maybe there is a bit of prejudice that has been created due to all the nonsense that afflicts the audiophile world (the unscientific one is meant) and also there is some emotional involvement in debates (which is not "scientific" but alas not fully extrovertable from man).
But I believe that there are more points of meeting than of quarrel in our discussion, so it's stupid to polarize and to accuse, so heavily. It is not in anyone's interest. And I don't exempt me from making a mistake in this sense.
As I have already said (or tried to), I do not believe it possible, but basically I can only hope that XTC will take hold and revolutionize the audio world. There is only to gain for audio enthusiasts. BACCH is definitely in the lead in this, with its unique technology. I respect the work behind it and wish them success.
But I think (just my understanding of things) some practical / conceptual obstacles are not fully minimized, so the actual cost shouldn't be left outside the discussion, from a MY consumer point of view.
Clearly it would only be positive to see facts and numbers that prove something. And we are here looking for this in fact, because we are passionate and the technology here is truly fascinating.
As soon as I can, however, I will try an XTC in my system, as much as it's worth a subjective proof.
Of course, the thread can be understood as closely linked to technical speeches, but we can't omit wider arguments, as happens in every single thread in the world practically. In the case, however, there are moderators who can / must intervene.
For example, when it comes to electric cars, it makes no sense to just talk about efficiency without talking about proof and sustainability. In the third millennium, global vision and science oriented thinking is needed, to me.
I hope we can agree on this.

EDIT: My epilogue
 
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Man, I sincerely believe that you are intelligent and have an uncommon ability to understand and analyze.
I have never meant that a scientific approach in development has not been used. Far be it from me. In fact I actually think BACCH is a truly remarkable piece of engineering, based on established scientific principles. I have no advantage in discrediting it, not even moral.
If that message has passed, I have expressed myself badly or have not been contextualized correctly.
I admit that I am not flawless in expressing myself and the translator does not even help.
My point is essentially that on the basis of publicly available information (at least those I've seen) there doesn't seem to be a way for us potential users to extrapolate the appropriate scientific certainties about the result that serve to justify such a high market price, both as regards the subjective and objective sphere of the matter. And so it shouldn't be appropriate to be blind supporters (nor detractors, for sure, due to the credibility of the source).
It is these kinds of reasonings that I think it's useful to do in this place.
Not just talk about science, nor about subjective experience.
I believe that ASR was born precisely because of the reckless market that is in the audio hobby.
Certainly there is a bit of prejudice that has been created due to all the nonsense that afflicts the audiophile world (the unscientific one is meant) and also there is some emotional involvement in debates (which is not "scientific" but alas not fully extrovertable from man).
But I believe that there are more points of meeting than of quarrel in our discussion, so it's stupid to polarize and to accuse, so heavily.
As I have already said (or tried to), I really do not believe it possible, but basically I can only hope that XTC will take hold and revolutionize the audio world. There is only to gain for audio enthusiasts. BACCH is definitely in the lead in this.
But there is still a long way to go and the practical and conceptual obstacles are not easy to overcome. And price is one of this.
I hope we can agree on this.
You do seem hung up on the price. So let's go over what you get for the price.

Babyface Pro 5 interface, $1,000.
Highly sensitive/calibrated ear microphones, which I was told by a distributor are more expensive than the interface.
Microphone to interface cabling, say $100
Very attractive case, say $400
A very sophisticated and customizable program. Whatever price you want to put on it.
One on one initial setup with the developer, about an hour. Say $300
One year, one to one, unlimited follow ups if needed. I've probably have had, at least, five hours of help from Edgar. This program and MacBook were totally new to me. Say $1500. And you are speaking to a highly regarded Princeton professor.

Compare that to going to an audio store and buying a pair of $6000 speakers and/or amplifier.
That price range may not be your's, but there is a large audiophile market that is.
 
The imaging itself does not shift with head movement

For front to back and side to side movement the sweet spot gets a little bit bigger but mostly and more importantly it stays completely consistent.
Thanks. Your response has resolved the fundamental concerns for me (or other BRIR users).

That goes away with the BACCH. The only limit on head movement within the sweet spot is horizontal rotation. You definitely can’t turn 90 degrees or full 180 degrees without losing the imaging. It holds up pretty much until your head turns past the angle of the speakers.
That's right. That's the limit of reality.
However, in the case of IEM/headphone virtualization+XTC without head tracking, everything is fixed (followed) and remains 360 degrees rather than 180 degrees.
Head tracking of other virtualization devices, including Bacch HP, seems to be aimed at improving spatial awareness. -> However, it is not related to XTC in this part because the value of XTC does not change at a fixed impulse and no calibration is required. (Of course, if this is to enjoy content such as VR/AR or games except XTC, the need and dependence of head tracking will increase For IEM/Headphone)

I think head tracking has excellent purpose and effect. So I think there are a lot of people who are curious about it.
And if anyone is curious about the speaker's BACCH XTC+Full Head Tracking system, BRIR+XTC will be an easier way to feel it. (Standing upside down, running around, everything is maintained)
 
Man, I sincerely believe that you are intelligent and have an uncommon ability to understand and analyze.
I have never meant that a scientific approach in development has not been used. Far be it from me. In fact I actually think BACCH is a truly remarkable piece of engineering, based on established scientific principles. I have no advantage in discrediting it, not even moral.
If that message has passed, I have expressed myself badly or have not been contextualized correctly.
I admit that I am not flawless in expressing myself and the translator does not even help.
I believe your points are balanced and well expressed in English.

At no point have you given the impression that BACCH is based on bad science.

You are simply dealing with someone who is indeed wildly unbalanced in his emotional over-defensiveness of his expensive ‘miracle filter’, and overstates its achievements, and argumentatively refuses to acknowledge its limitations. Over and over and over and over again….

Remember: even when Floyd Toole accurately described the limitations of this filter app, the same individual has since then engaged in dismissive handwaving and accused Dr Toole of bias. It has nothing to do with your English or translations.

I encourage you to continue as you have done, with confidence that you are not getting the overall message wrong. A certain individual is simply trying to twist your statements and make you doubt yourself.

Cheers
 
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You really think the team at Princeton are doing science with zero testing?
You are suggesting that they might be, or have been, conducting research projects targeted at testing the efficacy of filters that could be used to improve a commercial product that the head of the research unit is selling on the side? aka moonlighting?

I think the board at Princeton needs to be made aware of this. I will consider the best way to do this. Even if the Board cannot prove moonlighting, I think the blatant conflict of interest creates a potential for embarrassment that may force the board to remove Dr Choueiri from his position of influence over the direction of research.

Thank you for bringing this to my attention.
 
You are suggesting that they might be, or have been, conducting research projects targeted at testing the efficacy of filters that could be used to improve a commercial product that the head of the research unit is selling on the side? aka moonlighting?
No. Do your homework
I think the board at Princeton needs to be made aware of this.
Give em a call
I will consider the best way to do this. Even if the Board cannot prove moonlighting, I think the blatant conflict of interest creates a potential for embarrassment that may force the board to remove Dr Choueiri from his position of influence over the direction of research.

Thank you for bringing this to my attention.
No problem. Please call them and report back to us how it goes.

I take my first comment back. Don’t do any homework. Just call them.
 
I have highly highly directional speakers. And yet with the BACCH I feel for the first time the head vice has been truly removed from high end stereo.
May I ask how directional, ie what is their -6dB horizontal beamwidth angle (total angle side to side)
Or what speakers they are, if that's easier...thx.
 
@Justdafactsmaam , Is it possible for you to setup your speakers at about 20 degrees and recalibrate the BACCH cancellation and test the hard panned tracks again. AFAIK, BACCH is the best XTC out there and I am just curious of the hard panned sound projection since XTC not supposed to do what you are claiming unless the tracks are some sort of special effect like QSound and that can be explained.
 
You do seem hung up on the price. So let's go over what you get for the price.

Babyface Pro 5 interface, $1,000.
Highly sensitive/calibrated ear microphones, which I was told by a distributor are more expensive than the interface.
Microphone to interface cabling, say $100
Very attractive case, say $400
A very sophisticated and customizable program. Whatever price you want to put on it.
One on one initial setup with the developer, about an hour. Say $300
One year, one to one, unlimited follow ups if needed. I've probably have had, at least, five hours of help from Edgar. This program and MacBook were totally new to me. Say $1500. And you are speaking to a highly regarded Princeton professor.

Compare that to going to an audio store and buying a pair of $6000 speakers and/or amplifier.
That price range may not be your's, but there is a large audiophile market that is.
And for $6k it actually is a huge improvement. I swear that most audiophile gear cost mm difference Ithe owner can afford a better thesaurus.
@Justdafactsmaam , Is it possible for you to setup your speakers at about 20 degrees and recalibrate the BACCH cancellation and test the hard panned tracks again. AFAIK, BACCH is the best XTC out there and I am just curious of the hard panned sound projection since XTC not supposed to do what you are claiming unless the tracks are some sort of special effect like QSound and that can be

@Justdafactsmaam , Is it possible for you to setup your speakers at about 20 degrees and recalibrate the BACCH cancellation and test the hard panned tracks again. AFAIK, BACCH is the best XTC out there and I am just curious of the hard panned sound projection since XTC not supposed to do what you are claiming unless the tracks are some sort of special effect like QSound and that can be explained.
Not to butt in but what is your question about hard panned sounds? Depending on the recording (typically studio recordings) hard panned sounds can be placed seeming close to my ear or at 4-5 o’clock or 7-8 o’clock. I’m getting 20+ db XTC with Sanders ESL’s is a mildly treated large basement family room.
 
Not to butt in but what is your question about hard panned sounds? Depending on the recording (typically studio recordings) hard panned sounds can be placed seeming close to my ear or at 4-5 o’clock or 7-8 o’clock. I’m getting 20+ db XTC with Sanders ESL’s is a mildly treated large basement family room.

Earlier, he claimed the hard panned sound appears to come from 90 degrees and Choueiri mentioned about recordings accounted for crosstalk may not work well. I am just curious if is the same when speakers are position in the Ambiodipole position. I think Choueiri uses the term dipole to describe closely placed speakers but it need to be recalibrated as the all the settings will be changed.
 
Earlier, he claimed the hard panned sound appears to come from 90 degrees and Choueiri mentioned about recordings accounted for crosstalk may not work well. I am just curious if is the same when speakers are position in the Ambiodipole position. I think Choueiri uses the term dipole to describe closely placed speakers but it need to be recalibrated as the all the settings will be changed.
AS far as I understand BACCH makes placement less of an issue( which I haven’t tested) I have used it with narrow speaker angles (but different speakers). The sound field definitely wasn’t as wide but I’m not sure how much can be attributed to the speaker angle.
 
AS far as I understand BACCH makes placement less of an issue( which I haven’t tested) I have used it with narrow speaker angles (but different speakers). The sound field definitely wasn’t as wide but I’m not sure how much can be attributed to the speaker angle.

If BACCH makes placement less of an issue no harm trying otherwise placement is definitely an issue.

XTC and human hearing is well research field long before BACCH.
 
@Justdafactsmaam , Is it possible for you to setup your speakers at about 20 degrees and recalibrate the BACCH cancellation and test the hard panned tracks again. AFAIK, BACCH is the best XTC out there and I am just curious of the hard panned sound projection since XTC not supposed to do what you are claiming unless the tracks are some sort of special effect like QSound and that can be explained.
As soon as I get everything up and running. Hopefully today or tomorrow
 
Earlier, he claimed the hard panned sound appears to come from 90 degrees and Choueiri mentioned about recordings accounted for crosstalk may not work well. I am just curious if is the same when speakers are position in the Ambiodipole position. I think Choueiri uses the term dipole to describe closely placed speakers but it need to be recalibrated as the all the settings will be changed.
Hard pans are typically 60 to 90 degrees with varying proximity. I have had a few go past 90 degrees. But they are fairly rare.
The proximities tend to be congruent with the proximities of the other instruments that are not hard panned. Overall proximities also vary substantially from recording to recording.

As for hard pans “not working well” they sure work well for me! I hate hard pans landing on the speakers. For me that was an automatic demerit against any recording. Now every hard pan turns into something fun and often serves as a major improvement in the listening experience. Some of the studio recordings find a whole new life with an expanded sound scape.

I have enjoyed hearing studio recording sound stages go from a line of sounds ending at each speaker all in a pretty flat plane between them to a full three dimensional soundscape unbound in width and depth with distinctive proximities untethered to the speakers.

For sure what the BACCH does to transform minimalist acoustic recordings into teleportation to the concert hall experiences is an obvious and enormous leap in sound quality and realism. But I have enjoyed the benefits every bit as much on studio multitrack recordings
 
Sanders 10E
If BACCH makes placement less of an issue no harm trying otherwise placement is definitely an issue.

XTC and human hearing is well research field long before BACCH.
My placement is options are limited by aesthetic considerations and practical limitations of not hanging a dedicated listening room.
 
If BACCH makes placement less of an issue no harm trying otherwise placement is definitely an issue.

XTC and human hearing is well research field long before BACCH.
With the BACCH the filter seems to adjust to the speaker position. Edgar claims that even symmetry is no longer an issue. The filter will adjust level and time alignment to compensate.

And that can be a big advantage with full range speakers when trying to dodge room modes with speaker positioning
 
Hard pans are typically 60 to 90 degrees with varying proximity. I have had a few go past 90 degrees. But they are fairly rare.
The proximities tend to be congruent with the proximities of the other instruments that are not hard panned. Overall proximities also vary substantially from recording to recording.

As for hard pans “not working well” they sure work well for me! I hate hard pans landing on the speakers. For me that was an automatic demerit against any recording. Now every hard pan turns into something fun and often serves as a major improvement in the listening experience. Some of the studio recordings find a whole new life with an expanded sound scape.

I have enjoyed hearing studio recording sound stages go from a line of sounds ending at each speaker all in a pretty flat plane between them to a full three dimensional soundscape unbound in width and depth with distinctive proximities untethered to the speakers.

For sure what the BACCH does to transform minimalist acoustic recordings into teleportation to the concert hall experiences is an obvious and enormous leap in sound quality and realism. But I have enjoyed the benefits every bit as much on studio multitrack recordings
I think the problem with describing the subjective experience of listening to BACCH is that to the uninitiated it sounds like someone describing their own acid trip. Overall I think the users are very enthusiastic which often in audio is a clear sign of delusional thinking(not with BACCH). My own experience is that if my wife wants to make someone laugh she will goad me into explaining BACCH to someone who is not interested in audio.
 
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