Andrew Quint Reviews the Unique BACCH-SP Stereo Purifier

[jimbill]

Any specific information about the big upgrade coming?

There's a YouTube interview about it a bit back in this thread. He told me he's going to offer it separately for around $1,000. I think he was serious.
If you already have the Audiophile version or higher you get it for free.

 

[Dialectic]

There's a YouTube interview about it a bit back in this thread. He told me he's going to offer it separately for around $1,000. I think he was serious.
If you already have the Audiophile version or higher you get it for free.

Exciting! I'm glad I do...

 

[onion]

 

[MattHooper]

You could say that digital room correction is an "effects box" in that it changes the signal, but what arrives at your measurement microphone and your ears is certainly more accurate. The idea of DRC is to change the signal to compensate for inaccuracies caused by the speaker and room.

I don't think of the BACCH as an "effects box" myself. However, if someone is in the camp of wanting accuracy for the sake of more closely hearing "what they heard in the studio" then the BACCH technology certainly does raise the question of accuracy. Because obviously mixers are not listening through signals "corrected" by the BAACH.
And if the BAACH effect is a obvious and revelatory as so many listeners report, that suggests it is significantly different from the regular uncorrected stereo heard in the mixing theater.

The concept of BACCH is similar. It removes crosstalk, which is an inaccuracy created by a pair of stereo speakers in a room. Given that mastering engineers listen nearfield, they have less crosstalk. A typical home stereo setup has a farfield listening position, with speakers closer to an equilateral triangle, so you have more crosstalk. So yes, it is closer to what the mastering engineer heard.

I find that somewhat dubious.

I've worked in nearfield speaker situations, in plenty of different rooms and studios, doing post production sound, for over 30 years. I do not hear anything that jumps out as truly revelatory and distinct in my nearfield listening, vs listening to stereo from mid field or average listening distances. (And I experiment with various distances with my own stereo set up). Yes if I move closer to nearfield the sound will be somewhat different. But not different in the ways I keep seeing reported for the BAACH like "I can never go back to regular stereo listening again" and "it's a revelation" and hearing spatial effects completely revealed in ways one had never heard before from regular stereo listening.

So I haven't heard it yet and would love to, but I don't think one can have it both ways: If the BACCH produces a truly obvious, pronounced effect that you won't get from uncorrected stereo then it is surely a different effect than the average mixer hears from uncorrected stereo. Or...the perceptual effects are being exaggerated in the reports.

 

[slaweks]

So on some recordings, especially studio recording of electronic music, the effects are very strong, and yes, probably the mixers have not heard it, but it is very nice

 

[goat76]

I don't think of the BACCH as an "effects box" myself. However, if someone is in the camp of wanting accuracy for the sake of more closely hearing "what they heard in the studio" then the BACCH technology certainly does raise the question of accuracy. Because obviously mixers are not listening through signals "corrected" by the BAACH.
And if the BAACH effect is a obvious and revelatory as so many listeners report, that suggests it is significantly different from the regular uncorrected stereo heard in the mixing theater.



I find that somewhat dubious.

I've worked in nearfield speaker situations, in plenty of different rooms and studios, doing post production sound, for over 30 years. I do not hear anything that jumps out as truly revelatory and distinct in my nearfield listening, vs listening to stereo from mid field or average listening distances. (And I experiment with various distances with my own stereo set up). Yes if I move closer to nearfield the sound will be somewhat different. But not different in the ways I keep seeing reported for the BAACH like "I can never go back to regular stereo listening again" and "it's a revelation" and hearing spatial effects completely revealed in ways one had never heard before from regular stereo listening.

So I haven't heard it yet and would love to, but I don't think one can have it both ways: If the BACCH produces a truly obvious, pronounced effect that you won't get from uncorrected stereo then it is surely a different effect than the average mixer hears from uncorrected stereo. Or...the perceptual effects are being exaggerated in the reports.

I'm sure you have a DAW of some sort and a computer you can connect to your sound system, so why not download the simple uBACCH VST plugin and try it out, they have a 14-day free demo. The plugin has only one slider to set and that is the degree of the listening window and you are good to go.

I tried it out but wasn't too impressed. It worked nicely on some tracks, especially recordings made with some sort of stereo micing technique, but when it comes to panned multi-mono recordings it can go either way, some work well while others will sound almost broken. What was clear to me was the music should be done with the BACCH filter in mind to make sure the mix would not fall apart.

One of the worst examples I heard was one of those old ping-pong stereo recordings with The Beatles, you know one of those where all the instruments are located in the left channel and the singer is located in the right channel. With normal playback a recording like that doesn't sound too awful, but with the BACCH filter applied it no longer just sounds like instruments come from the left side of the room and the singer from the right side of the room, the channels are now completely detached and isolated from each other and it sounds exactly as wrong as such recording sounds in a pair of headphones.
I know it's an extreme example, but even in modern multi-mono mixes it's not uncommon that individual instruments are hard-panned all the way out to either the left or the right side, and those individual sound elements will suffer the same way as in the Beatles example and when that happens it sounds very unnatural with the BACCH filter.

But I don't want to sound too negative. If your main listening habits are natural stereo recordings based on inter-channel time difference and natural room acoustics, the BACCH filter can sound amazing and can give you that extra sensation of envelopment.

 

[Justdafactsmaam]

I don't think of the BACCH as an "effects box" myself. However, if someone is in the camp of wanting accuracy for the sake of more closely hearing "what they heard in the studio" then the BACCH technology certainly does raise the question of accuracy.

Unless some one has a magic box that recognizes the original control room of every different recording and simulates it for their system, no one is hearing what was heard in the studio

Second, I wonder how often the musicians, recording engineers and producers sat in front of the console and said “thank god we don’t have any imaging outside the speakers! That would just ruin our goals for this recording!”

 

[Gwreck]

Unless some one has a magic box that recognizes the original control room of every different recording and simulates it for their system, no one is hearing what was heard in the studio

Second, I wonder how often the musicians, recording engineers and producers sat in front of the console and said “thank god we don’t have any imaging outside the speakers! That would just ruin our goals for this recording!

 

[Gwreck]

It seems that the way BACCH works from my experience is that it homogenizes the stereo image between different 2 channel systems. For the measurement based BACCH speaker placement is not the most critical aspect for a good effect.

 

[Justdafactsmaam]

It seems that the way BACCH works from my experience is that it homogenizes the stereo image between different 2 channel systems. For the measurement based BACCH speaker placement is not the most critical aspect for a good effect.

It doesn’t homogenize it. It just fixes it. The resulting fix is more consistent than the unfixed versions.

You can take a pair of speakers in a room and change the sound stage substantially by changing the speaker positions and listener position. It changes substantially because it substantially affects the cross talk.

Once the BACCH fixes the cross talk the speaker and listener positions become far far less of a factor for imaging. Which is a big benefit. It frees you to focus on other issues when positioning your speakers and listening position.

 

[Gwreck]

It doesn’t homogenize it. It just fixes it. The resulting fix is more consistent than the unfixed versions.

You can take a pair of speakers in a room and change the sound stage substantially by changing the speaker positions and listener position. It changes substantially because it substantially affects the cross talk.

Once the BACCH fixes the cross talk the speaker and listener positions become far far less of a factor for imaging. Which is a big benefit. It frees you to focus on other issues when positioning your speakers and listening position.

I agree. You said it better than I was trying to say. By fixing the imaging it homogenizes imaging between systems.

 

[Dialectic]

Yes, it homogenizes imaging among systems, de-homogenizes it among recordings.

No hyperbole here...

 

[Justdafactsmaam]

I agree. You said it better than I was trying to say. By fixing the imaging it homogenizes imaging between systems.

Yes but to the degree that the XTC can be achieved with the filter. The results will vary with the amount of room reflections and the speaker’s radiation patterns.

I also highly highly recommend that the BACCH only be judged with the head tracking and custom filters. You are barely half way there with the entry level version and you have to deal with the head in a vice problem. I would not advocate the BACCH if the entry level version was the only offering. The head tracking is so important. And with the new room correction filter it’s even more so a vital element of the system.

 

[MattHooper]

Unless some one has a magic box that recognizes the original control room of every different recording and simulates it for their system, no one is hearing what was heard in the studio

Agreed. That's one reason why I don't worry about "recreating what they heard in the studio."

I was only talking to the folks who do have that type of goal. And so my response was to Keith W who was suggesting that the BACCH does indeed get one closer to what the mixers heard.

 

[sweetsounds]

BACCH ORC was released today, I will install it tonight and report back hopefully in the next couple of days.
So far I use a full-frequency DRC with Acourate with very positive results.

> BACCH-ORC requires acoustic measurements with the BACCH-BM in-ear microphone and is therefore available only for the Audiophile Edition and above.
> The BACCH-ORC module can be added to BACCH-dSP at any time for $1000. However, in appreciation of the trust and enthusiastic support of our existing customers, we are offering a free perpetual license for the BACCH-ORC module to all those who have purchased BACCH-dSP Audiophile (or a higher edition level) by March 3, 2024, and whose 1-year Tech Support and Version Update Service Plan has not expired by that date.

$1000 is above the price of DIRAC Live with Bass Correction ($729) and way above the price of AudioLense ($180 - $400) and Acourate ($370) (which is a much more technically complete, but not so easy approach).


@Keith_W: your positive results using uBACCH in the rotated room set-up are confirming my experiences. You need to get rid of the first-order side wall reflections to get crosstalk cancelation working. Only the direct sound cross-talk gets eliminated. Still, BACCH is another step up over uBACCH for me.

 

[Dialectic]

Will install ORC and report results this weekend.

 

[Keith_W]

Thanks guys. I would like to see a description of the workflow as well (not just the results). I have so many questions, I don't know where to start!

- what are the advantages of binaural correction vs. omni mic?
- how automated is it?
- what does it correct?
- how much manual intervention / over-ride is possible?
- how does it do time alignment?
- what does the verification sweep in ORC look like vs. REW?

 

[Dialectic]

Has anyone else configured ORC yet?

There are a lot of settings. In particular, I am wondering if other users have played with the six different free-field target curves.

 

[Gwreck]

Has anyone else configured ORC yet?

There are a lot of settings. In particular, I am wondering if other users have played with the six different free-field target

Has anyone else configured ORC yet?

There are a lot of settings. In particular, I am wondering if other users have played with the six different free-field target curves.

I have not had a day off in 2 weeks so once I get caught up with things I had to put off then I can get to it.

 

[Gwreck]

The thing I notice mostly about ORC is that I thought my system was sounding pretty good prior now I realize I was wrong…so wrong. The effect is dramatic enough that it seems that somehow BACCH now makes thing worse if it’s unused in the audio chain.