Card carrying objectivists

[Blumlein 88]

Doesn't choice supportive bias apply to most brands?

It does, but some brands have more fanatical followings than others. Schiit has an unusually supportive group for unusually sub-standard gear.

 

[tomelex]

I dunno, there's some very clever ideas in the Kii speakers, and the measurements (as shown in Jan Didden and Paul Wilke's review) bear out the claims. I've heard a few models at hifi shows and thought that, considering the venue, they were quite good. Not my favorite speakers ever, but ones I could be happy with.

Sadly, my wife has vetoed any of my favorites. The only reason I even have what I do is because I owned them before I met her.

maybe if you bought speakers that looked like plucked chickens.......

 

[Arnold Krueger]

Problem is, the folks who do "listening" tests with peeking call what they do "empirical."

The problem is that they seem to be confused and therefore wrong about what they are testing. They pretend that they are testing audio gear, but in fact they are testing their opinions, their preconceptions, their illusions, and their free associations, all stimulated by random volume levels.

 

[Arnold Krueger]

There is a card? where do I get one?

Join the AES and then get a qualifying endorsement from Stan Lipshitz.

 

[Arnold Krueger]

I call my philosophy of audio Reliable Subjectivism.

 

[Cosmik]

Something that has just occurred to me is that BACCH is a perfect example of where 'objectivism' as practised by some audiophiles would be shown to be faulty.

For example, many objectively-minded audiophiles think that if they measure the in-room frequency response of a setup they like, this should then be a target for a different setup in a different room; in doing so, they will be duplicating the goodness of the original setup goes their thinking.

Logically, on the same basis, if we measure the response of BACCH to sine sweeps and other simple test signals, we should be able to take those frequency response results and get close to them using graphic equalisers and the like, and we will have duplicated BACCH..!

But it is only because we know beforehand how crosstalk cancelling algorithms work (fundamentally in the time domain) that we know that this would be fruitless. Because we know how they are designed, we know what measurements would make sense and, perhaps more interestingly, we know that measurements would be kind of pointless. It would be interesting to see Stereophile's measurements page for BACCH; they would be better off reprinting the source code for the readers to peruse.

Well, I suggest that the same is true for 'room correction' and 'target curves' and the like. The measurements are crude, meaningless irrelevances that display time domain phenomena in the form of the contents of frequency bins, smoothed and with the phase thrown away. If you were to display them in full, they would be meaningless because of their complexity, and if you display them 'simplified' they are even more meaningless. The approach is 180 degrees wrong. If you look at the design of the 'source code' you know what's going on; if you try to measure the output, you are just blundering about.

 

[svart-hvitt]

Something that has just occurred to me is that BACCH is a perfect example of where 'objectivism' as practised by some audiophiles would be shown to be faulty.

For example, many objectively-minded audiophiles think that if they measure the in-room frequency response of a setup they like, this should then be a target for a different setup in a different room; in doing so, they will be duplicating the goodness of the original setup goes their thinking.

Logically, on the same basis, if we measure the response of BACCH to sine sweeps and other simple test signals, we should be able to take those frequency response results and get close to them using graphic equalisers and the like, and we will have duplicated BACCH..!

But it is only because we know beforehand how crosstalk cancelling algorithms work (fundamentally in the time domain) that we know that this would be fruitless. Because we know how they are designed, we know what measurements would make sense and, perhaps more interestingly, we know that measurements would be kind of pointless. It would be interesting to see Stereophile's measurements page for BACCH; they would be better off reprinting the source code for the readers to peruse.

Well, I suggest that the same is true for 'room correction' and 'target curves' and the like. The measurements are crude, meaningless irrelevances that display time domain phenomena in the form of the contents of frequency bins, smoothed and with the phase thrown away. If you were to display them in full, they would be meaningless because of their complexity, and if you display them 'simplified' they are even more meaningless. The approach is 180 degrees wrong. If you look at the design of the 'source code' you know what's going on; if you try to measure the output, you are just blundering about.

Bacch is a dynamic effect box, isn’t it?

Room compensation algorithms are fixed, steady state, right?

Measuring a fixed window into Bacch would be apples to oranges; using a fixed measurement window for a dynamic system.

 

[Dialectic]

Bacch is a dynamic effect box, isn’t it?

Room compensation algorithms are fixed, steady state, right?

Measuring a fixed window into Bacch would be apples to oranges; using a fixed measurement window for a dynamic system.

It's still possible to measure BACCH's effectiveness using intraaural microphones. If one were to compare (a) what arrives at the ipsilateral ear to (b) what is on the recording being played back, I'm sure that BACCH would lessen the difference between (a) and (b).

 

[Cosmik]

Bacch is a dynamic effect box, isn’t it?

Room compensation algorithms are fixed, steady state, right?

Not sure I can make the distinction so clearly. Is a delay line a dynamic effects box? Do two cross-coupled delay lines and some EQ constitute a dynamic effects box? If an algorithm responds the same for all signal levels and is not being modulated by the signal, can it be described as dynamic? (If it has head tracking then I might be more inclined to call it dynamic - but not if you hold your head still).

If I feed a steady state sine wave into BACCH I will get a steady state sine wave out. It is only because I know beforehand how crosstalk cancellation works that I would know to measure it with transients and the like.

The average 'objectivist' might, upon hearing it without knowing what it was, think "What a smashing stereo setup - great imaging with some recordings. I must measure its in-room curve, make a note of the speakers and take down the name of the supplier of the acoustic treatments so I can duplicate it at home." They would be wrong...

 

[svart-hvitt]

Not sure I can make the distinction so clearly. Is a delay line a dynamic effects box? Do two cross-coupled delay lines and some EQ constitute a dynamic effects box? If an algorithm responds the same for all signal levels and is not being modulated by the signal, can it be described as dynamic? (If it has head tracking then I might be more inclined to call it dynamic - but not if you hold your head still).

If I feed a steady state sine wave into BACCH I will get a steady state sine wave out. It is only because I know beforehand how crosstalk cancellation works that I would know to measure it with transients and the like.

The average 'objectivist' might, upon hearing it without knowing what it was, think "What a smashing stereo setup - great imaging with some recordings. I must measure its in-room curve, make a note of the speakers and take down the name of the supplier of the acoustic treatments so I can duplicate it at home." They would be wrong...

If you put Bacch through and AD converter, you should be able to recreate Bacch.

True, a room compensation algorithms cannot reproduce Bacch. You’d need an AD converter for that.

Conventional room compensation algorithms are not an adequate representation of an effect box (like Bacch).

 

[Cosmik]

If you put Bacch through and AD converter, you should be able to recreate Bacch.

Well it is just an algorithm, but I don't think you can automatically say that you could reproduce the contents of any black box by studying its input and output - it could be arbitrarily complex and you might never be able to feed in enough signals to establish exactly what it does. But you could certainly record its output for later replay. But not necessarily if any of the circumstances have changed, such as using it in a different room.

BACCH has a frequency response - if you feed it with a test signal and measure the output. BACCH has a distortion measurement - probably very low, limited only by the resolution of the calculations and the DAC resolution. BACCH has noise measurement - ditto. BACCH appears to suffer from stereo crosstalk (which is, in fact, what reduces crosstalk at the listening position). If you think that such 'objective' measurements can help you capture how it works, you would be wrong.

Ordinary speakers in a room are not a million miles off being like BACCH conceptually. Two inputs, two speakers, with delays, feedback, crosstalk and frequency-selective attenuation and boosting (acoustic, not software). And 'objective' audiophiles think that they *can* interpret how it 'works', decide that it needs correcting, and correct it by making simple measurements. This is no different from thinking that your measurements of BACCH can tell you how well it is working and whether it needs 'improvement' by making a few changes to a few simple parameters.

Even if you have some prior idea of what BACCH is aiming to achieve and make measurements using in-ear mics and look for crosstalk elimination, you still won't get a clean result, because the aim is not to achieve an anechoic perfect replica of the signal at each ear. It certainly won't tell you what you would need to do to improve it or whether, in fact, it isn't working optimally.

 

[Theo]

Still, doesn't BACCH improve the subjective listening quality, although it is far from perfect? Same stands for room correction as long as it reduces the impact of standing waves in the low frequency range. The question is, as objectivists, how much are we ready to invest to please our senses (I mean hearing, of course...). IMHO, objectivists are using the scientific approach to improve, not to create a perfect world which they know is impossible... I guess that apart from electrodes implanted in the brain, there is no way we can reproduce perfection (and even...).

 

[Arnold Krueger]

Bacch is a dynamic effect box, isn’t it?

Room compensation algorithms are fixed, steady state, right?

Measuring a fixed window into Bacch would be apples to oranges; using a fixed measurement window for a dynamic system.

Based on an examination of https://www.theoretica.us/bacch-sp.html the purpose of BAACH appears to be to provide a transformation from a specially made binaural (2-channel) recording made with BAACH-BM Pro or something like it, to playback using one the the three BAACH-SP DSP processors or something like them., driving a stereo pair of speakers. One possibly peculiar characteristics of the BAACH system components is reliance on 2-channel microphones, 2-channel recording, and 2-channel playback.

There is more information here: https://www.princeton.edu/3D3A/BACCH_intro.html

https://www.princeton.edu/3D3A/Publications/BACCHPaperV4d.pdf

Offhand, the necessary transformation need only involve linear transformations, IOW time delays, frequency response manipulations and phase shifts. Nonlinear transformations such as those resulting in dynamic gain variations, THD or IM would seem to be irrelevant.

A classic AES paper about Binaural can be found here:


http://www.aes.org/e-lib/browse.cfm?elib=471

"Stereophonic Earphones and Binaural Loudspeakers"
Author: Bauer, Benjamin B.
Affiliation: CBS Laboratories, Stamford, CT
JAES Volume 9 Issue 2 pp. 148-151; April 1961
Publication Date: April 1, 1961
Permalink: http://www.aes.org/e-lib/browse.cfm?elib=471

"Stereophonic sound is recorded for reproduction over spaced-apart loudspeakers. When earphones are substituted for loudspeakers the stereophonic space perspective is incorrectly portrayed. This paper describes two electrical networks which allow earphones to ube used in place of loudspeakers without substantial loss of space perspective. One of them is designed to work from low impedance sources and feed into high impedance earphones. The second, which is a dual of the first, is more suited to medium impedance sources and low impedance earphones. It is pointed out that these networks can also be used to convert a binaural program for reproduction over a stereophonic loudspeaker system. This is done by reversing the phase of one amplifier channel and of the corresponding loudspeaker"