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Dr. Edgar Choueiri explains BACCH

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.

Why would want to use XTC for live monitoring? For video, I don’t remember having any lip sync issues with XTC.

XTC like BACCH meant for hearing stereo sound. I don’t think you want to incorporate them in multi channel or Dolby ATMOS unless you want 3D sound with two speakers for those without AVR.
 
Again, did you read my initial post?

I have read that FAQ and understand what is said as I have pretty good knowledge of recording and mixing music. The FAQ explains what types of recordings XTC works best with, and to what types of recordings can be problematic where the sollution sometimes can be to dial down the XTC or even turn it off completely.

One interesting thing in the FAQ is the description of natural XTC that will differ depending on the speaker setup, distances, and room acoustics. With my speaker system I have a fair bit of natural XTC as I listen at a fairly close distance in a small equilateral triangle, and in a fairly treated listening room with the first reflections coming in almost 20 dB down from the direct sound, so the ratio of direct sound from the speakers is high vs the reflected sounds from the room. The only thing that isn't optimal from an XTC view is that my speakers have a wide radiation, but that is a sound characteristic I prefer when it comes to speakers.

As I've tested the uBacch filter on my own mixes containing several hard-panned sound objects, I know that it altered it in a way that I would have liked mixing it differently if I had monitored it with the uBacch filter applied.
 
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Why would want to use XTC for live monitoring? For video, I don’t remember having any lip sync issues with XTC.
This:
As I've tested the uBacch filter on my own mixes containing several hard-panned sound objects, I know that it altered it in a way that I would have liked mixing it differently if I had monitored it with the uBacch filter applied.
 
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. Be
I too thought barrier supposed to be the ideal XTC but getting at least 10dB attenuation is almost impossible with physical barrier.

Using digital XTC you can achieve pretty good attenuation but not without some compromises. Tonal changes is one of them which you can solve or solved with the $10 AmbiophonicsDsp.

Room influence is something that I find not so critical for XTC. I am not sure if anyone speaking from a proper anechoic like room experience with XTC but for XTC ( digitally) to work you don’t need an anechoic like room. In fact, about 20 years ago all my experiment took place in a normal room without any treatment.

But a good cancellation is a steep learning curve which I failed miserably and need to be told by others how it sounded so bad. I never gave up until really understood the fundamentals but with the help of the pioneer himself. I think many are actually in my shoes Then right now. The potential is there but it requires you to experiment and be open minded.

All criticism that we see now about BACCH is something I have seen with Ambiophonics which supposed to be the free for the public. Nothing changed but I hope BACCH could do the impossible.
 
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
Thanks for this information Mieswall, especially suggesting certain recordings. I had BACCH-dsP installed about 3 weeks ago and was previously using a sound processor named QOL but BSG Technologies (no longer available) that had received rave reviews by The Absolute Sound. This processor did provide a wider and deeper soundstage on some recordings although I have no idea how it worked. This was replaced with the BACCH-dSP and it has expanded this so much more. I love it and never want to be without it again. Some recordings by pop artists (for lack of a better word) are incredible, including Billie Eilish's new album and a lot of James Blake recordings.
 
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They do. There is uBACCH which is available on a 14 day trial.

I read this thread and wonder why the detractors don't download uBACCH and try it. Then they will understand. BACCH does not alter the tonality, does not make it sound "phasey". It improves the definition of the image and widens the soundstage.

I got pretty tired of this debate a long time ago, good on you @Justdafactsmaam for having the energy.
I tried to try it but it's having problems with distortion and clicking/breakup. Not sure what that's all about. It changed the tonal balance slightly, seeming to add a bit of mid-bass weight, but the imaging effect was so similar to my 3 speaker setup it was difficult for me to decide which I liked better in that respect.
 
I tried to try it but it's having problems with distortion and clicking/breakup. Not sure what that's all about. It changed the tonal balance slightly, seeming to add a bit of mid-bass weight, but the imaging effect was so similar to my 3 speaker setup it was difficult for me to decide which I liked better in that respect.
Sounds like it wasn’t working properly. There are some binaural recordings by Chesky that allow you to check how well it’s working
 
I tried to try it but it's having problems with distortion and clicking/breakup. Not sure what that's all about. It changed the tonal balance slightly, seeming to add a bit of mid-bass weight, but the imaging effect was so similar to my 3 speaker setup it was difficult for me to decide which I liked better in that respect.

I never had the problems you are experiencing with the uBACCH plugin, I think you have a problem in your audio chain, maybe you just need to lower the gain in the DAW or whatever you use for playback.
 
Sounds like it wasn’t working properly. There are some binaural recordings by Chesky that allow you to check how well it’s working
It's definitely not working correctly. The distortion is very audible. I use Audio Hijack as the host to run the plug-in and I've had problems with some other 3rd party plug-ins, mostly convolvers, which can produce similar instability and distortion. It might clear up with future updates. Some of these issues seem to come and go with OS and software updates.
 
I never had the problems you are experiencing with the uBACCH plugin, I think you have a problem in your audio chain, maybe you just need to lower the gain in the DAW or whatever you use for playback.
I tried that. It seems gain independent. VU meters show good margins from clipping. But now that I'm thinking about it I'm remembering that there's an input device that seems to cause a lot of problems from time to time. It's a Optical to USB converter, which I use to bring sound from the TV into the computer. I'll unplug that and see if it helps.
 
I’ve used Element as plugin host and Blackhole-2ch for the plumbing, both free. I didn’t get distortions or drop-outs, provided the buffer was large enough (I usually use 2048 because, why not?).

1719271504773.png
 
That could be the problem. Audio Hijack and other virtual cable didn’t caused distortion and didn’t work correctly for me too.
I'll see if I can get something else to do everything I need, or maybe combine things somehow. Audio Hijack is providing me with crossovers and EQ right now, so somehow all that has to keep happening. I suppose the uBacch trial period is going to end before I find something that works for me, unless it only goes on the clock when it's in use. Not a big deal. It's expensive enough that I won't be jumping on it any time soon anyways. I've already heard crosstalk reduction good enough to create a full 180 degree sound field when the speakers are only 20 degrees apart, with some sounds seeming to be close to one ear or the other, so I'm pretty sure I know most of what it's all about.
 
I'll see if I can get something else to do everything I need, or maybe combine things somehow. Audio Hijack is providing me with crossovers and EQ right now, so somehow all that has to keep happening. I suppose the uBacch trial period is going to end before I find something that works for me, unless it only goes on the clock when it's in use. Not a big deal. It's expensive enough that I won't be jumping on it any time soon anyways. I've already heard crosstalk reduction good enough to create a full 180 degree sound field when the speakers are only 20 degrees apart, with some sounds seeming to be close to one ear or the other, so I'm pretty sure I know most of what it's all about.
I think your system configuration will be in a more stable XTC state than ubacch.
 
Bacch / uBacch / race / other xtc software / physical barriers / physically cancel with additional speakers
have a few question for XTC users as above. (for Collecting human personal data or experience)
I want to hear from everyone who has experience.

1. What is the Listening distance between you and the speaker? What size space and how far or close it is
2. What is the angle of the speakers? (e.g. 30 degree angle based on listening position.) If it's multi-channel XTC, how many degrees each
3. What is the impulse of your early reflection in the 0-5, 10ms range in Room? For example -10db. -20db. Or -40db.
 
1. What is the Listening distance between you and the speaker?
About 2.5 meter.
What size space and how far or close it is
You mean the speakers? They are ESL about 6 x 3 feet each. Speakers are just about 3cm from one another.

What is the angle of the speakers?
20 degrees.

3. What is the impulse of your early reflection in the 0-5, 10ms range in Room?
Above 40dB attenuation. Room RT is below 0.2s. Didn’t really hear any diff with the XTC even when it was above 0.3s.
 
This would likely do more to promote the product than people waving their arms around on audio forums.

The rabid arm wavers on this forum are doing no favours whatsoever in terms of "promotion" for this product. Quite the opposite in fact.
 
The rabid arm wavers on this forum are doing no favours whatsoever in terms of "promotion" for this product. Quite the opposite in fact.
The folks whose see us as “rabid arm wavers” already made up their minds. Which is fine. Their loss. BACCH4Mac systems are already on back order. Growth has to be controlled or customer service suffers.

I’m not interested in promoting it. My interest here is countering blatant misinformation and mischaracterizations of it. This being a science based audio forum and all.
 
1. What is the Listening distance between you and the speaker? What size space and how far or close it is

3.2m between MLP and speaker. The speakers are set up on the long wall of a 6m x 7m room in an equilateral triangle.

2. What is the angle of the speakers? (e.g. 30 degree angle based on listening position.) If it's multi-channel XTC, how many degrees each

60 degrees. Both speakers toed in to the listener.

3. What is the impulse of your early reflection in the 0-5, 10ms range in Room? For example -10db. -20db. Or -40db.

Here's my ETC for the first 200ms.

1719985612285.png
 
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