Dr. Edgar Choueiri explains BACCH

[Justdafactsmaam]

I say for the universal version (if I say generic someone is offended it seems)

No. It’s neither. It’s the basic version that does not allow you to make personal custom filters or use head tracking. It’s not about being offended it’s about correcting misinformation.

There is far too much of it on ASR when it comes to the BACCH

Even if I add a saturator plugin I get a more pleasant sound in many cases,

Given the fact that you have zero experience with the BACCH how do you reach this conclusion?

I repeat, well-made stereo systems already do the job they were designed for very correctly.

Well made stereo systems were designed to mask, muddle and obfuscate spatial cues on stereo recordings? What do you base this assertion on?

If I really want spatial audio with head tracking I take some AirPods and get a really better result at a much lower price, even where the stereo track is upmixed in Dolby Atmos.

Given you have zero experience with the BACCH upon what do you base your conclusion that you will get better results with AirPods and Dolby Atmos?

 

[Davide]

Well made stereo systems were designed to mask, muddle and obfuscate spatial cues on stereo recordings?

Spatial cues on audio tracks are designed to be listened with a zero crosstalk system?
In my opinion no, if not binaural recordings and if music is mixed in studio monitors. In fact listening on headphones, where you have zero crosstalk, is artificial and crossfeed is beneficial. Shouldn't it be an opposite way to compensate for the effect?

Given you have zero experience with the BACCH upon what do you base your conclusion that you will get better results with AirPods and Dolby Atmos?

If you consider crosstalk a problem, they introduce zero crossover effect, so they can best convey intended spatial cues, without limitations of listening area and maybe with more precise head tracking because it is based gyroscopes and not on a video camera. (but this is just a my complementary assumption knowing the inertial systems of aircraft, maybe I'm wrong, no data in this regard).
And even if they weren't perfect, they cost about $ 200, they do other functions, maintain a bit of commercial value, so IMO they are a better product to experience spatial audio.
Obviously it is a supposition and it doesn't mean that with an XTC system as good as it can be BACCH can't be better for other reasons (I believe we should investigate this).
It is only to respond to the assumption that crosstalk is entirely to be ousted.

 

[Justdafactsmaam]

Spatial cues on recordings are designed to be listened with a zero crosstalk system?

There is no singular answer. What we can say is that recording engineers and artists know that the recording will be played back on a multitude of different systems. I can’t tell you what any recording was specifically “designed” to be played back on unless it is explicitly stated by the engineers and/or artists.

And neither can you.

No, if not binaural recordings and if music is mixed in studio. In fact listening on headphones, where you have zero crosstalk, is artificial and crossfeed is beneficial.

It’s all artificial. Headphones or speakers. And you are kidding yourself if you think headphones are not ever used to monitor recordings. I literally witnessed a major recording recorded using headphones and only headphones to monitor that recording.

They introduce zero crossover effect, so they can best convey intended spatial cues, without limitations of listening area and with much more precise head tracking because it is based gyroscopes and not on a video camera.

So essentially you are basing a preference on hype rather than actual testing

 

[mieswall]

Here we are... a group of people that had NEVER listened the product, that clearly don't even read the article that started this thread (dealing with most to their complaints), and only based on their preconceptions (and their much more limited knowledge on the subject than Choueiri, for sure) of what can or cannot be done with XTC, try to convince to the ones that listen B4M each day that...

When listening Beethoven's pastoral (Symph #6) by the Kammerakademie directed by Manacorda (Sony, 2023), those oboes and clarinets that you can pinpoint not only in span but depth, that you can even tell the distante BETWEEN them, that all of the sudden are listening all of the ambience (resonance, reverberation) of the concert hall; where somehow your listening room turns into a huge listening space; and then when turning off the dsp, with everything collapsing flat between the speakers without almost any reverberation at all, at best presenting a faint image of the orchestra groups as a whole... somehow this collapsed presentation resembles better what was truly registered by the sound engineer or what you hear at the concert hall (because, you have herd at least once a symphony in a decent concert hall, right?). That's about "type 1" recording techniques.

They also try to convince us that in "type 2, artificial end" recordings, like Garbarek's 'In Praise of Dreams' (ECM, 2005), where Jan not only plays his usual saxes with heavy reverberation -almost impossible to perceive in normal stereo -, his dialogs with the viola each perfectly delineated in space each one located in a steady place, but also synthesizers playing amazing spatial tricks that instantly transport you to the stratosphere; with Manu Katche percussions spread (as usual in ECM) at the whole width of the scenario; where Kashkashian's viola, with its reverb and chord vibrations so well defined that you can almost see the air surrounding her... are all gimmicks that would surely upset the recording engineer (James Farber), because somehow... that's not what he tried to do, and it's not closer of what he listens in his studio of controlled acoustics, with very close field monitors. That he obviously would prefer the multiple reflections blurring the image of any live listening room -as the one we all have in our homes-, where that reverb almost doesn't exist at all, where the synths spatial games just disappear. That those reflections and blurring are... quite more faithful to the intentions he had when mixing this recording in optimal conditions.

But of course, if they listen a faint resemblance of all that played by a pair of Wilson Sabrinas... that's OK. That's true hi-fi.

BTW, with a cheap software-based XTC (like Soundstage Shaper) at best you can compare it to the more limited uBacch. But, probably without the phase and timing corrections (instead of frequency) that allows BACCH not to colour the signal. And of course without knowing a bit about your room acoustics, dispersion patterns of your loudspeakers, or your own head morphology, all precisely captured by B4M mics when making measurements.

This product is for music lovers, not people staring at graphs (although those are nice too in B4M, btw), completely scared at the possibility that something may be better to what they know or own. And yet, BACCH is based in more deep scientific knowledge on the subject than most of us would be able to achieve in a lifetime.

So, sorry for you.

 

[goat76]

I’ll walk you through it. These are all quotes from you

“The problem with a "user-applied" filter is that that will severely alter the sound from what the mixing engineer heard while making all the delicate mixing decisions.”

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

“What's in the data is not important, what's important is what the audio engineer heard while making all the mixing decisions,”

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

“It's not about replicating the sound in the studio, it’s about what they didn't hear in the studio while making all the mixing decisions that is the problem.”

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

And just to be uber clear

Goal post position #1 “what’s important is what the audio engineer heard while making all the mixing decisions”

Goal post position #2 “It’s not about replicating the sound in the studio”

All of the above things I said means the same thing. There are no moving af any goalposts. Is that really that hard to understand?

"The problem with a "user-applied" filter is that that will severely alter the sound from what the mixing engineer heard while making all the delicate mixing decisions. What's in the data is not important, what's important is what the audio engineer heard while making all the mixing decisions. It's not about us replicating the sound in the studio, it’s about what the audio engineer didn't hear in the studio while making all the mixing decisions that is the problem."

And my example that you never addressed

RVG recorded in stereo but did his mix in mono using an Altec 604B mounted in the left ceiling corner of his control room. A control room with no bass traps, diffusion or absorption.

So given your assertion that “It’s not what’s in the data (the actual recording) that’s important it’s what the audio engineer heard that’s important does it not follow that any playback of an early Blue Note recording that deviates from the original mono mix played back on an Altec 604B stuck in one ceiling corner of a small room with no acoustic treatment is inferior and that listening to a stereo mix of those same recordings on a system such as say…. Amir’s stereo with the Revel Salon Ultima IIs is plainly the wrong way to listen given it will sound nothing like what RVG heard?

I didn't comment it because of the simple fact that I don't find your little anecdote very important for the general discussion we are having. It's that simple.

 

[Justdafactsmaam]

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

Which means he didn’t hear how it would sound on your system either

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

Which means he didn’t hear how it would sound on your system either

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.

Which means he didn’t hear how it would sound on your system either

All of the above things I said means the same thing. There are no moving af any goalposts. Is that really that hard to understand?

You moved the goal posts and you present it as if it’s unique to the BACCH and ignore the fact that it applies to all other playback systems including yours. So along with moving goal posts you are also cherry picking. Congrats on trying to rationalize your logical fallacies with additional logical fallacies

"The problem with a "user-applied" filter is that that will severely alter the sound from what the mixing engineer heard while making all the delicate mixing decisions.

So will your system. More cherry picking

What's in the data is not important, what's important is what the audio engineer heard while making all the mixing decisions. It's not about us replicating the sound in the studio, it’s about what the audio engineer didn't hear in the studio while making all the mixing decisions that is the problem."



I didn't comment it because of the simple fact that I don't find your little anecdote very important for the general discussion we are having. It's that simple.

And yet it clearly represents the reality of recording control rooms in comparison to audiophile’s home systems. So IOW you don’t find that pervasive reality very important.

Good to know when considering the content of your posts.

 

[Davide]

Here we are... a group of people that had NEVER listened the product, that clearly don't even read the article that started this thread (dealing with most to their complaints), and only based on their preconceptions (and their much more limited knowledge on the subject than Choueiri, for sure) of what can or cannot be done with XTC, try to convince to the ones that listen B4M each day that...

When listening Beethoven's pastoral (Symph #6) by the Kammerakademie directed by Manacorda (Sony, 2023), those oboes and clarinets that you can pinpoint not only in span but depth, that you can even tell the distante BETWEEN them, that all of the sudden are listening all of the ambience (resonance, reverberation) of the concert hall; where somehow your listening room turns into a huge listening space; and then when turning off the dsp, with everything collapsing flat between the speakers without almost any reverberation at all, at best presenting a faint image of the orchestra groups as a whole... somehow this collapsed presentation resembles better what was truly registered by the sound engineer or what you hear at the concert hall (because, you have herd at least once a symphony in a decent concert hall, right?). That about a "type 1" recording techniques.

They also try to convince us that in "type 2, artificial end" recordings, like in Garbarek's 'In Praise of Dreams' (ECM, 2005), where Jan not only plays his usual saxes with heavy reverberation (almost impossible to perceive in normal stereo -his dialogs with the viola each perfectly delineated in space, each one located in a steady place-, but also synthesizers playing amazing spatial tricks that instantly transport you to the stratosphere; with Manu Katche percussions spread (as usual in ECM) at the whole width of the scenario; where Kashkashian's viola, with its reverb and chord vibrations so well defined that you can almost see the air surrounding her... are all gimmicks that would surely upset the recording engineer (James Farber), because somehow... that's not what he tried to do, and it's not closer of what he listens in his studio of controlled acoustics, with very close field monitors. That he obviously would prefer the multiple reflections blurring the image of any live listening room -as the one we all have in our homes-, where that reverb almost doesn't exist at all, where the synths spatial games just disappear. That those reflections and blurring are... quite more faithful to the intentions he had when mixing this recording in optimal conditions.

But of course, if they listen a faint resemblance of all that played by a pair of Wilson Sabrinas... that's OK. That's true hi-fi.

BTW, with a cheap software-based XTC (like Soundstage Shaper) at best what you can compare it to the more limited uBacch. But, probably without the phase and timing corrections (instead of frequency) that allows BACCH not to colour the signal. And of course without knowing a bit about your room acoustics, dispersion patterns of your loudspeakers, or your own head morphology, that are all precisely captured by B4M mics when making measurements.

This product is for music lovers, not people staring at graphs (although those are nice too in B4M, btw), completely scared at the possibility that something may be better of what they know or own. And yet, BACCH it's based in more deep scientific knowledge on the subject that most of us would be able to achieve in a lifetime.

So, sorry for you.

"Here we are" or "this product is for music lovers" sounds bad to me. However...
You can even have a personal concert hall or studio with the real artists/engineers at your service H24 if you have enough money.
It's the best ever audio system.
There is no need to say that I need to listen to it to know how good it is. It necessarily sounds more "true" then my stereo. I don't doubt.
But what you can't convince me is that your system has better value, or price/realism/emotionalism/functionalism ratio then my stereo, only with the technical arguments currently available in the website (which I have read, yes).
It's a personal judgement. This is my point.
I'm not saying XTC, and BACCH especially, doesn't give improvement in perception, in fact.
Indeed, given the credibility of the source I am quite sure that it will also do so in a very good way.

EDIT: My epilogue

 

[Justdafactsmaam]

"Here we are" or "this product is for music lovers" sounds bad to me.

It sounds bad to you? I thought you had never heard it. Has that changed?

However...
You can even have a personal concert hall or studio with the real artists/engineers at your service H24 if you have enough money.
It's the best ever audio system.
There is no need to say that I need to listen to it to know how good it is. It necessarily sounds more "true" then my stereo. I don't doubt.
But what you can't convince me is that your system has better value, or price/realism/emotionalism/functionalism ratio then my stereo.

You have made it clear that you have made up your mind without auditioning that you personally don’t think it’s worth the money.

I don’t think anyone is trying to get you to change your mind on your personal sense of value for your money

 

[Tim Link]

I WISH!!!

Although, if I understand correctly, the very-narrow-pattern Sanders electrostats are arguably even better suited for BACCH processing than the deliberately wider-pattern SoundLabs are.

I think it's true for all crosstalk reduction schemes. The effect becomes more powerful when room effects are removed. Don Keele sitting outside with his crosstalk barrier setup here: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiddffvLbKMpmijFH1dBYbXTD6EM0qutXTu5w7cim7w5kLq0M-b23WEUVkYYTdN1_kJcN9SzfhyUhCyGgT8p20c_GX1fHvjazfI8BGf-Uk5H6cU8ZSJRhl3TkIe6aANk06nhwiWb9Sfx_-VletBMNnfDSWKGzV4iBuxefNW6qdocF2qLq-tQq1Exx-NDek/s2871/Stereo Crosstalk - Archimago's Room - Mattress Divider crosstalk attenuate + Old Photos.jpg

Annoying to me, nothing so far seems to sound as good as a barrier in your face.

 

[Davide]

It sounds bad to you? I thought you had never heard it. Has that changed?

You have made it clear that you have made up your mind without auditioning that you personally don’t think it’s worth the money.

I don’t think anyone is trying to get you to change your mind on your personal sense of value for your money

Yeah... for the last time, I have almost convinced myself with available arguments that for what BACCH does in theory it is not worth the price to me, so I'm not interested to try it, although admitting that I could love the experience in the end, also in presence of possible limitations and variability (one person filter, dependence on the room and system).
If there are further theoretical or factual elements, let's expose them as well, I mean, the forum should be of use to this.
Otherwise, we agreed that there is subjectivity on the whole matter, especially about value.
But from the insistence and meticulousness with which you respond, in general, it seems to me that you do not accept this.
If you are convinced of how you spent your money, why reply so promptly?
No criticism in this regard, the comparison whether constructive or informative is welcome.
But here it becomes a wall against wall.
We are just trying to frame a product with the available elements. If we only have theory, then we put all the theory on the table, not just the good part. Which doesn't mean going against it, obviously. But this seems unclear...

EDIT: My epilogue

 

[jimbill]

Which means he didn't hear how his mix would sound after a filter like Bacch is applied.



Which means he didn't hear how his mix would sound after a filter like Bacch is applied.



Which means he didn't hear how his mix would sound after a filter like Bacch is applied.



All of the above things I said means the same thing. There are no moving af any goalposts. Is that really that hard to understand?

"The problem with a "user-applied" filter is that that will severely alter the sound from what the mixing engineer heard while making all the delicate mixing decisions. What's in the data is not important, what's important is what the audio engineer heard while making all the mixing decisions. It's not about us replicating the sound in the studio, it’s about what the audio engineer didn't hear in the studio while making all the mixing decisions that is the problem."



I didn't comment it because of the simple fact that I don't find your little anecdote very important for the general discussion we are having. It's that simple.

1. How does BACCH enhance the spatial imaging of "studio-mixed" recordings without altering the sound intended by the mixing engineer?
   In light of the arguments in FAQ #14 above, we can now address the case of “studio-mixed” recordings, which represent the vast majority of commercially available recordings. In such recordings, the mixing engineer (and sometimes with input from the artist(s) and/or producer(s) and, to a lesser extent the mastering engineer,) concoct an artificial stereo image from stems (most often mono stems) mostly through level panning (and, much less often, time or phase panning) between the left and right channels. Mixing to produce a realistic, pleasing or engaging stereo image is an art involving both technical knowhow and esthetic decisions.
   Many mixing engineers are truly ingenious masters. It goes without saying that their final product deserves the utmost respect and that a good hi-fi reproduction system should not degrade or fundamentally alter their construct. It is also very true that virtually all commercially available mixed recordings were mixed while monitoring on monitors without XTC.
   Depending on the techniques used and esthetic decisions made, these concocted recordings range over a wide spectrum: on one end of the spectrum are recordings aiming to emulate a real acoustic environment (e.g. a jazz club). Let us call this end of the spectrum the “pseudo-realistic end”. On the other end of the spectrum are recordings that have no binding ties to realism, and instead aim to evoke sensations, or project certain esthetic expressions (e.g. the chimes in Pink Floyd’s well-known Time track on their Dark Side of the Moon album). Let us refer to this end of the spectrum as the “artificial end”.
   We will now consider what happens when such recordings are played back through XTC.
   On the pseudo-realistic end of that spectrum, most of the arguments made in FAQ#14 above hold, to some extent, since the mixing engineer is essentially using at least an analog of ILD and ITD to produce a “realistic” stereo image like a stereo mic would, and all that XTC does is remove the artificial cieling on the ILD and ITD limits imposed by the speakers during playback. Most relevant in this context is reverb. During mixing, reverb is added algorithmically or through convolution with a real space impulse response (with the latter technique yielding far more realistic reverb). In both cases XTC unlocks the perceived reverberation from the speakers and project it into 3D space. It does so because the perception of a realistic 3D reverb is caused by late reflections (the diffuse field) arriving at the left and right ears at almost random arrival times (i.e. with low L-R correlation, in the parlance of acoustics) and without XTC the sound at the right and left ears would be highly corelated since the sound from each of the L or R channels reaches both ears. Such highly L-R corelated sound causes the listener to perceive the reverb to be largely restricted spatially a region that is mostly where the speakers are. It is hard to imagine a mixing engineer who would object to his mix reproduced with a reverb that is more 3D and less “stuck to the speakers” (as long as the tonal and level balance between the direct and reverberant sound is not altered. (BACCH is a patented form of advanced XTC that causes no alteration whatsoever to that balance as described in this standard, but highly technical book chapter.) In fact, one of the most noticeable and striking aspects of listening through a BACCH filter for the first time is the immediate sense of being in a real 3D space due to the higher L-R sound decorrelation that reverb is meant to cause at the ears.
   On the “artificial end” of the studio-mixed recordings spectrum defined above, the mixing engineer concocts an image whose panned sources constitute an artificial stereo image that does not aim to be a reflection of a reality, but rather an esthetic or artistic construct. While mixing that image the engineer is choosing to place sources in a space that is largely between the two speakers. However, as is well-known by audiophiles, even a stereo playback system without XTC can image in a 3D, albeit relatively restricted, spatial region around the speaker (often called “the soundstage”). The main reason such imaging occurs without active XTC is because the listener’s head, by shadowing the contralateral ear from the loudspeaker (i.e. the speaker on the opposite side) creates a natural crosstalk cancellation that is highly effective at higher frequencies (i.e. frequencies whose wavelengths are smaller than that of the human head). It should be clear that this natural XTC (which can be seen in the measurement shown in the first plot in FAQ#14) depends on the span between the speakers, the distance between the head and the speakers, the radiation pattern of the speakers, and the extent and relative strength of reflections in the room. A larger speaker span, a shorter distance to the head, a more directive speaker, and a higher ratio of direct-to-reflected sound, all lead to higher values of this natural XTC. This is mainly why different stereo systems in different rooms with different listener-speakers placements, can achieve different levels of “3D imaging”.
   A mixing engineer in a given studio with a certain set of stereo speakers concocts a stereo image while hearing a soundstage the spatial extent of which depends largely on the above listed parameters of the particular monitoring setup in the studio. An audiophile playing back the resulting recording through a good hi-fi stereo system at home has generally no way of knowing what these parameters were when the mix was produced, but still strives to get a good measure of a 3D soundstage. Indeed “3D soundstage” imaging of a playback system is one of the holy grails for audiophiles and audio critics. By choosing and tuning his gear and listening room to enhance such soundstage the audiophile does not betray the intent of the mixing engineer as long as the enhancement of the spatial extent of the soundstage does not come at the expense of a change in the spatial balance or tonal content of the recording during playback. It is very possible that the 3D imaging of an audiophile’s playback system has significantly better 3D imaging capability than that used by the engineer while monitoring the mix. No one would object if this were the case, or accuse the audiophile of betraying the engineer's intent.
   For such recordings (on the “artificial end” of the spectrum,) XTC cannot pretend to enhance realism during playback since the stereo image was artificially concocted in the first place. However, like in the case of natural XTC, adding more XTC actively to enhance the spatial extent of the soundstage, without altering the balance or tonal content of the recording, (which is the essential characteristic of BACCH XTC) does not strictly betray the intent of the mixing engineer since the spatial extent of the artificial soundstage was not prescribed by him. Of course, this argument becomes more tenuous if XTC leads to extreme spatial panning, which can only happen for hard left or right panned sources in the absence of reflections (e.g. in an anechoic chamber, a hard left or right panned sound source played back through a pair speakers with high levels of XTC, without any ILD or spectral cues added to the sound, would lead to the sound being perceived to be very close to the left or right ears of the listener, as if wearing headphones). Such extreme imaging does not occur in real listening rooms with typical levels of direct-to-reflected sound ratio.
   Of course, the level of active XTC during playback can be dialed down (in BACCH-dSP there is an “XTC percentage” slider that allows doing just that) but it should be clear from the above arguments that this is not recommended for acoustic recordings or for recordings on the “pseudo-realistic end” of the “studio-mixed” recordings spectrum. Moving towards the “artificial end” of the spectrum, the question of betraying the original intent of the engineer does indeed become a valid objection, but only to the extent to which XTC alters the tonal character and spatial balance of the recording (which BACCH, by design, does not do at all) and to the extent to which high levels of XTC can result in jarring extremely panned images, which can occur with BACCH but only in near-anechoic environments and with recordings having extremely panned mono images. The latter issue can be addressed by dialing back the XTC level (or in extreme but very rare cases, by bypassing XTC!).

Again, did you read my initial post?

 

[Justdafactsmaam]

Yeah... for the last time, I have decided providing some arguments that for what BACCH does in theory it is not worth the price, so I'm not interested to try it, although admitting that I could love the experience in the end, also with all its limitation and variability.
We agreed that there is subjectivity on the whole matter, especially about value.
But from the insistence and meticulousness with which you respond, in general, it seems to me that you do not accept this.
If you are convinced of how you spent your money, why reply so promptly?
No criticism in this regard, the comparison whether constructive or informative is welcome.
But here it becomes a wall against wall.

If you have decided you don’t want to spend the money why are you participating in his discussion at all? I reply promptly to your misinformation because I think correcting misinformation is worth doing, particularly on a forum that is in no small part committed to doing exactly that.

I’m baffled as to how you can conclude that I am not “accepting” your decision not to spend money on the BACCH when I wrote “I don’t think anyone is trying to get you to change your mind on your personal sense of value for your money”

 

[theREALdotnet]

RVG recorded in stereo but did his mix in mono using an Altec 604B mounted in the left ceiling corner of his control room.

I don’t think RVG remasters are deserving of the acclaim they’re getting. I find they mostly sound terrible (from a stereo imaging point of view), and I have no problem believing that he mixed using nothing than a single speaker and VU meters.

 

[Justdafactsmaam]

I don’t think RVG remasters are deserving of the acclaim they’re getting. I find they mostly sound terrible (from a stereo imaging point of view), and I have no problem believing that he mixed using nothing than a single speaker and VU meters.

If you are talking about the RVG supervised remasters those were crap…IMO but I quite like the Music Matters, Analog Productions and even the Tone Poet vinyl remasters.

With that said even with many of the better reissues, in conventional stereo the hard pans are ugly. Different ball game with the BACCH.

Some folks seem to be philosophically attached to those hard pans sitting in the speaker. For me it was the Achilles heel of the early Blue Note stereo recordings. Well that and the piano sound.

 

[theREALdotnet]

I read this thread and wonder why the detractors don't download uBACCH and try it.

Turns out this is terrible advice, if your aim is to promote BACCH. At least in my system, uBACCH stinks.

BACCH does not alter the tonality, does not make it sound "phasey". It improves the definition of the image and widens the soundstage.

I can only surmise that uBACCH and BACCH4Mac are entirely different beasts, because the above is not my experience. uBACCH will widen the soundstage, yes, but not in a pleasant way.

My system is a DLBC setup with stereo speakers and currently two subwoofers. Listening room and speaker placement are symmetrical. The room is dedicated to music listening and fairly well treated with bass absorbers, first reflection absorbers and diffusers as well as ceiling absorbers and diffusers. I get very good imaging out of recordings that have it in them. I inserted uBACCH between source and Dirac Live Processor (because that’s where things are still 2-ch). I also tried uBACCH with Dirac out of the chain or partially (gain and/or delay compensation) disabled. Dirac and uBACCH do not seem to interfere with each other in a deleterious way, what I observed below was largely the same with or without Dirac.

Initial setup of uBACCH was dead easy and quick. Both measurements and by-ear tuning landed on the same spot, 28 degrees. I had to dial down the centre gain all the way to -3dB, because otherwise the tonality would shift and the soundstage would get pancaked back to front. With centre gain at -3dB, sources right in the middle between L and R were left untouched by uBACCH, they sounded virtually the same with uBACCH on or off.

It’s the off-centre sources where uBACCH goes to work. It will stretch or smear them, the further from the centre the bigger the effect, in an arch extending outside and around the speaker towards the listening spot. In well done acoustic recordings of symphony orchestras, chamber or jazz bands this wreaks havoc with imaging. Instruments or instrument groups that used to be pin-point will get blurred and lose focus. Sources placed at the extremes of the soundstage get transformed completely. For example, in the 1960 Decca recording of Carnival of the Animals (LSO, Skitch Henderson), the double bass portraying the elephant (about 8 min into the track) is placed pretty far right. In my system it appears somewhat to the right of the right speaker and about a metre behind it. With uBACCH enabled it turns into a dark cloud that fills most of the right side of the room, extending up to the listing position. The instrument is being replaced by a sound effect.

I tried lots of recordings of classical and jazz that way, from single-microphone captures to conventional takes, none of them improved with uBACCH and all of them suffered loss of imaging clarity.

There are some recordings that didn’t seem to suffer. Madonna’s Immaculate Collection, for example, being recorded in Q-Sound, has these all-round-your-head effects in several of the songs. These effects are amplified, and I can see how people might consider this an improvement. Likewise, I can imagine techno, trance, chill, etc. to be enhanced by uBACCH. There may be other kinds of music that will benefit, that I have yet to try.

I’ve got two weeks for the trial and I will use them to try uBACCH on many more and varied recordings. If I find anything new or interesting I’ll report back. For now, I wouldn’t spend ten bucks on this plugin, let alone a thousand.

YMMV.

 

[STC]

Spatial cues on recordings are designed to be listened with a zero crosstalk system?
No, if not binaural recordings and if music is mixed in studio. In fact listening on headphones, where you have zero crosstalk, is artificial and crossfeed is beneficial.

Interaural crosstalk cannot be incorporated into a recording. It happens after sound exists from the speakers which is beyond anyone’s control.

The end result may be desirable where you can get enhanced sound for bass or at the lower frequencies.

Headphones listening is without IAC. You are correct about that. But adding the reasoning why it is unnatural is something about how human decode sound. Crossfeed is just a poor attempt and nothing to do with IAC cancellation concept for loudspeakers playback.

 

[theREALdotnet]

During installation of uBACCH and reading through the docs I believe I read something like 10ms.

Found it:

A quick note on latency

Currently, our plugin doesn’t report latency to DAWs for delay compensation. However, there is indeed a very short latency added when listening through the (latest versions of the) plug-in, under 10ms.

(https://bacch.atlassian.net/wiki/spaces/BS/pages/2020605953/u-BACCH+How-To+Guide)

 

[Keith_W]

It’s the off-centre sources where uBACCH goes to work. It will stretch or smear them, the further from the centre the bigger the effect, in an arch extending outside and around the speaker towards the listening spot. In well done acoustic recordings of symphony orchestras, chamber or jazz bands this wreaks havoc with imaging. Instruments or instrument groups that used to be pin-point will get blurred and lose focus. Sources placed at the extremes of the soundstage get transformed completely.

That is fair enough. I have noticed the same on some of my recordings as well. I think in another post on ASR I called it a "wide angle lens effect" because the way it sounds is similar to how a wide angle lens images - the objects at the centre look normal, but objects to either side are stretched out. It looks as if you are describing the same thing.

I have been listening to uBACCH for months now and I have found that it does this with some recordings, but not all of them. I think it has something to do with your choice of music. Listen to Schubert lieder (singer + piano) - if it is not close mic'ed, both singer and piano appear in sharp focus but the ambience stretches around nicely. If it is close mic'ed, the singer sounds as if they have a 5 foot wide mouth and you are inside the piano. In my experience, less than 10% of the music I listen to are negatively affected by uBACCH. The rest are improved.

IMO, XTC is heavily dependent on the recording and your system. Any system that has a lot of reflections will have less pronounced XTC effect, especially side reflections. So - speakers placed too close to the side walls, listening position too close to the rear wall, speakers with a wider arc of radiation, and so on. I am not sure whether the classic Ambiosonics speaker placement (virtually next to each other like the World Trade Center in NYC or the Petronas KLCC twin skyscrapers) is to enhance XTC or to get the speakers as far away from the side walls as possible. And as you have experienced, some recordings benefit, some will suffer.

I have other friends who have uBACCH or BACCH4Mac. None of their systems are optimized for BACCH. With one of them, the effect of BACCH is virtually un-noticeable. I listened to his system before I purchased uBACCH, and I told him that if this was a BACCH demo I would be unconvinced. The other system had a slightly more pronounced effect, but it was nowhere close to the descriptions I had read online. I was VERY skeptical if it would make a difference, and kept the money in my pocket. My opinion only changed after I downloaded uBACCH and gave it a try.

So is it worth almost a thousand bucks? What i'll say is that the effect is definitely noticeable, and for me it is mostly beneficial. For others it is strongly beneficial. And for some others, it makes no difference or it may even be deleterious. It is "YMMV" for the reasons mentioned. I do not think it can be dismissed on theoretical grounds, because you do not know if you would benefit if you don't try it.

 

[STC]

Found it:

(https://bacch.atlassian.net/wiki/spaces/BS/pages/2020605953/u-BACCH+How-To+Guide)

I am just curious here as to why we are concerned with latency. How will it affect the listener of the recordings?

 

[Davide]

If you have decided you don’t want to spend the money why are you participating in his discussion at all? I reply promptly to your misinformation because I think correcting misinformation is worth doing, particularly on a forum that is in no small part committed to doing exactly that.

I’m baffled as to how you can conclude that I am not “accepting” your decision not to spend money on the BACCH when I wrote “I don’t think anyone is trying to get you to change your mind on your personal sense of value for your money”

Disinformation to me means treating the topic only from certain points of view without admitting contradiction where objectively there are elements of subjectivity (regarding the concept of spatial reference for non-binaural tracks) and where the theory, in addition to potential advantages, also includes limitations (to one person) and elements of variability (due to the room, speakers, directivity, phase correlation, etc.).
I started participating in the discussion to best focus the relationship between these elements and the price, but I understand that we have not many objective elements here (measurements).
You have decided that it is worth what it costs.
No one can say you're wrong. It's subjective. So why are you here?
To reject any argument that clashes with your subjective point of view?
I already get your point, I don't agree with it.

EDIT: My epilogue

I am just curious here as to why we are concerned with latency. How will it affect the listener of the recordings?

It is interesting for me to know if XTC processing is suitable in live monitoring and/or video playback or it introduces too much latency.