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Dr. Edgar Choueiri explains BACCH

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.
 
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 advantage in discrediting it, not even moral. The opposite.
Great. Let’s put that behind us.
My point is essentially that on the basis of publicly available information (those I've seen, but anyone is free to link more where I missed some) there doesn't seem to be a way for us potential users to extrapolate the appropriate scientific certainties 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 not saying that development tests don't exist, much less that it doesn't work. Just that on viewable information it shouldn't be appropriate to drawn conclusions about the product (both of objective and subjective sphere) and be blind/reckless supporters (nor detractors, for sure, due to the credibility of the source).
As an owner of the BACCH4Mac I can tell you that part of the custom filter building process objective measurements are taken of the crosstalk of the system with the in ear microphones. After the filter is built you can get measurements of the actual XTC achieved by the filter. So those measurements are plentiful.

100% perceptual XTC happens at about -25 db.
Sure home demo could be a good thing, but it seems not available 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).
I’m not sure what an ABX test would achieve. ABX is the gold standard for detecting audible differences. I don’t think there is any meaningful debate about whether or not it makes an audible difference. I think even blind preference tests would have to be uniquely blind in that the subjects would have to be completely uninformed about what is being tested.
Amongst people who are in the know the effect is so unmistakable that tests couldn’t really be blind.
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, with its unique technology. I respect the work behind it and wish them success.
It won’t revolutionize the audio world. Audiophilia is a niche market in the audio world. Nothing that happens in our niche will revolutionize audio.

What the BACCH does offer is a massive leap forward in our ability to listen to 70+ years of stereo recordings. That is my opinion. It’s an audiophile product. Already niche in nature. Whether or not it becomes a “revolution” in the audiophile world is yet to be determined. It’s a diverse group of enthusiasts to say the least with an extremely wide gamut of beliefs.

IMO it’s market share is less of an issue. It’s actual impact in one’s system is a much bigger point of contemplation. No other single element in high end audio has the degree of impact as does the BACCH. Again, my opinion.

That gap between BACCH based systems and non BACCH based systems is going to be a hot topic in high end audio moving forward
But I think (but nobody believe me) there is still a long way to go and the technical, practical and conceptual obstacles seems partly hard to overcome, so the actual product value shouldn't be left outside the discussion, from a MY consumer point of view.
Of course not. But it is important to separate what the product actually does and individual consumers’ determination of value for the money
 
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.
Never thought of it that way. A very fair point
Overall I think the users are very enthusiastic which often in audio is a clear sign of delusional thinking(not with BACCH).
Very true! Beyond that the BACCH actually does achieve an advancement in spatial audio that shatters what was largely assumed to be an unbreakable glass ceiling in two channel stereo. And as such common opinion was this kind of advancement could only be achieved with multichannel.

Had I not heard it in my room I too would have been very skeptical of the claims.

I also think that anything that makes such a large change is always going to have to endure an acclimation period where the user has to suss out whether it’s impact is mostly shock value or if it represents a rare large scale game changing improvement.

Big differences are, rightly so, big red flags
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.
That’s funny
 
This was the basis for XTC. You want each channel sound to be isolated to each ear.

That's the thing that makes XTC incompatible with hard-panned sounds, they simply cannot work if each channel sound is isolated to each ear.

The thing that needs to be done to solve the problem is if the XTC program somehow could detect hard-panned sounds, and exclude them from being canceled. That would likely make the XTC compatible with pretty much all recordings.
 
That's the thing that makes XTC incompatible with hard-panned sounds, they simply cannot work if each channel sound is isolated to each ear.

The thing that needs to be done to solve the problem is if the XTC program somehow could detect hard-panned sounds, and exclude them from being canceled. That would likely make the XTC compatible with pretty much all recordings.
In your opinion. In my opinion it is a solution to a legacy problem which is hard pans landing on speakers and screaming out “YOU ARE LISTENING TO SPEAKERS!!”

Your opinion is valid. But only as a personal opinion. It’s not a compatibility issue. It is a personal preference issue.

And once again I must point out that the XTC level is adjustable. Better option than excluding hard pans only
 
You are missing the point…
In real life, there is not a matter of “opinions” to hear or not hear an instrument with both your ears even if it’s not positioned straight in front of you, but that will not be the case with XTC if each channel sound is isolated to each ear, and that's what makes XTC incompatible with hard-panned sound objects.
 
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You are missing the point…
It is not a matter of “opinions” to hear or not hear an instrument with both your ears even if it’s not positioned straight in front of you, but still, that’s what happens if each channel sound is isolated to each ear, and that's what makes XTC incompatible with hard-panned sound objects.
What about the playback with XTC makes the hard panned sound incompatible?
 
What about the playback with XTC makes the hard panned sound incompatible?
Sorry, I rewrote my message while you quoted me. I think the renewed message answers your question.
 
Sorry, I rewrote my message while you quoted me. I think the renewed message answers your question.
Most hard panned sounds are limited to early stereo recordings and it seems the intentions was to place them directly in their right and left speaker. Modern recordings are much better at making a false sound stage. If a record is putting hard panned sounds at 9 and 3 it’s easy to dial back the percentage of XTC or turn it off entirely. Theoretica is completely transparent about what types of recordings have the most realistic playback with BACCH and studio recordings are at the bottom.
 
You are missing the point…
No, I understand your point. I just don’t agree that it extends beyond personal preference
In real life, there is not a matter of “opinions” to hear or not hear an instrument with both your ears even if it’s not positioned straight in front of you, but that will not be the case with XTC if each channel sound is isolated to each ear, and that's what makes XTC incompatible with hard-panned sound objects.
Your argument died at “real life.” As Edgar himself pointed out in his response to the effect the BACCH has on studio recordings, there is no “real life” reference with studio multitrack recordings.

And you are wrong that it is “incompatible” with hard pans. The BACCH is quite effective with hard pans. That’s a fact.

Again….you may not like the results. But that is your preference not a universal truth. I do like the results. That is my personal preference not any universal truth.

Either way, there is no pre existing reality with a studio recording that serves as an objective reference. This is a fact that is agreed upon by Dr. Floyd Toole, Dr. Edgar Choueiri and James D. Johnston. This is not an argument by authority. Their arguments that there is no underlying reference with studio recordings or almost any commercial recordings are well documented. I can post those arguments if you feel they are failed arguments.

Your own example of an early Beatles stereo mix served to support this. The Beatles never heard the stereo mixes prior to their release. All the monitoring was done in mono. So there is no basis for any claim that there is a right or wrong way that listen to those stereo mixes. All you are left with is preferences
 
Most hard panned sounds are limited to early stereo recordings and it seems the intentions was to place them directly in their right and left speaker. Modern recordings are much better at making a false sound stage. If a record is putting hard panned sounds at 9 and 3 it’s easy to dial back the percentage of XTC or turn it off entirely. Theoretica is completely transparent about what types of recordings have the most realistic playback with BACCH and studio recordings are at the bottom.

No, hard-panning is still a common thing in the modern mixing of rock, pop, and electronic music. Many of today's mixing engineers even only use hard-left, phantom center, and hard-right when panning things in their mixes.

I know that Theoretica is fairly transparent about it and the information is written in their FAQ. The solution is to dial it back or even turn it off completely, and they have implemented it because they fully well know hard-panned sounds don't work with fully optimized XTC, as those are most commonly meant to be heard by both ears and not isolated to just the closest one. It's strange and unnatural to hear an instrument with just one ear just because it happens to be coming from a side position, I'm sure you agree with that. :)
 
Most hard panned sounds are limited to early stereo recordings and it seems the intentions was to place them directly in their right and left speaker. Modern recordings are much better at making a false sound stage. If a record is putting hard panned sounds at 9 and 3 it’s easy to dial back the percentage of XTC or turn it off entirely.
It is. But so far I haven’t turned it off for any recording. IME the BACCH benefits studio recordings too. I’ll offer up a prime example. Early Blue Note stereo recordings. RVG recorded early on in stereo only so he could do a mix to mono with more control over the balance of the instruments.

There was zero consideration to a stereo mix. RVG did all of his monitoring in mono. But we have stereo mixes and those mixes have hard pans.

Those hard pans are IMO the Achilles heel of otherwise very good jazz recordings. With the BACCH those hard pans jump off of the left and right speakers and form a cohesive set of spatial images on a substantial sound stage that does an amazing job of suspension of disbelief.

The results are IMO a massive improvement over the non filtered stereo playback.

Personally I just don’t care whether it’s by design or a happy accident.

I am willing to speculate that if we could do blind preference tests with testees that did not have a horse in the race that with these great recordings we would have near 100% preference for a BACCH based playback over conventional stereo or original mono as they were heard and possibly intended to be heard

Which points to a philosophical argument regarding “what was heard in the studio” and artists/engneers/producers’ intent. Even if we could use these as objective references, and we can’t, but even if we could, it creates another glass ceiling for subjective excellence.

Is what RVG heard in his control room with the old Altec speaker shoved in a ceiling corner in mono really the “ideal” way to hear those recordings? The objective standard?

I say no. There are subjectively better speakers, better rooms/room treatments and formats. I see no good reason to limit our personal aesthetic values to arbitrary dated artifacts of recording and playback technologies
Theoretica is completely transparent about what types of recordings have the most realistic playback with BACCH and studio recordings are at the bottom.
And context is important. Studio recordings are at the bottom with or without the BACCH.
 
As for hard pans “not working well” they sure work well for me! I hate hard pans landing on the speakers.

Pure stereo supposed to create illusion of phantom images between speakers. Hard panned isolate them to one channel and in stereo it will emerge from the speakers. The purpose of XTC is suppress the hearing ability to localize the speakers! You only want to hear the encoded ILD (mostly) and ITD . most panning do not have ITD info. So XTC shouldn’t land the sound from the speaker but when only one sound is coming from the speaker and in the absence of other cues it will decoded to be coming from the speaker. With XTC since the other ear is not perceiving any sound the direction is determined by the ear apparent direction that the sound seemed to emerge and even then if it coming from the position of the ear then it is different from how you would naturally localize the sound in nature as one ear localization is different from two ears in the absent of ILD and ITD.

In the earlier days I was trying hard to prove that it would still be possible with speakers at 60 degrees cancellation but after experimenting with different position ambiodiopole was where the perfect cancellation takes place. That time I had Harbeth and therefore easy to do experiments now with Sound Labs it is impossible to the size and weight of the speakers. Otherwise, I would made samples and show why 60 degrees is not feasible but that doesn’t mean it can’t be done but that would be beyond mere XTC.

I am eagerly awaiting your feedback when you done the Ambiodipole position.
 
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