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Dr. Toole's comments in anticipation to his new book on Acoustics and Psychoacoustics

Cosmik

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No. The training involves identifying what part of frequency response is wrong in a speaker (i.e. colored). It does not create preference for sound. Just take the test and you will see.
But the line of mine you quoted and disagreed with didn't say anything about training creating preference..? Nor did the post afterwards..?

What I said was that if a person can be shown to prefer (another word for "rate highly") a speaker that 'measures well' (I didn't specify the measure, but you say it is "uncolored") then that makes them - in Harman's eyes - a 'better' listener. And, indeed, Harman says:

"The training has identified significant differences among listeners in their abilities to reliably identify and rate these distortions. ... This information can form an objective basis for selecting the most reliable and skilled listeners..."

"Training" in that paragraph's context, means "evaluation after training". So in other words, when evaluated, the listener's ability is inferred from his preferences for 'a measure' (i.e. lack of spectral distortion).

Further down in my post, I then go on to say
Because better listeners prefer speakers that measure well, this shows that our measurements are indicative of absolute quality.
... which I think is the logical leap too far.
Therefore listeners can be trained to be better judges of quality by learning to maximise their score with speakers that measure well.
 

Fitzcaraldo215

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I always find Dr. Toole's views stimulating and obviously very credible. The terrific thing is that he is also a very engaging writer who says things with great clarity.

Given my great love of hi rez Mch audio, I find much reinforcement of and likely explanations for my own very positive anecdotal experience with it.

Hmm, the book comes out in August, and my birthday is in late August. So, the book is definitely going on my birthday list.
 

amirm

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... which I think is the logical leap too far.
"Therefore listeners can be trained to be better judges of quality by learning to maximise their score with speakers that measure well."

Again, that is now how it works. Just take the training. You will find that there is nothing in there about anything measuring well. You listen with your system as is as the reference. The software then changes the response and asks you to identify it. You could have really bad measuring system and still get trained to identify what is changed in the response.

Think of this simple hypothetical. We add a sub to a system and turn it way up. "Boom, boom, boom." All of us will identify that being "wrong." We would hear the exaggerated bass and call it unnatural. Real life doesn't sound that way. Trained and untrained listeners would have the same reaction.

What a trained listener can do is better identify that the problem area is in 100 to 200 Hz for example than 20 to 100 Hz. Or hear the exaggeration at lower levels.

It just happens that when we measure speakers with these in-built response differences, we find that listeners -- trained or otherwise -- gravitate toward the speakers that have the least ups and downs (coloration). That should be celebrated as it allows us to make much faster measurements to assess fidelity than relying on listening tests.

Imagine if the outcome was one where it was some complex random set of factors that was not the same among many listeners. It would be a hell of a lot worse than where we are.
 

RayDunzl

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Jakob1863

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<snip> NOT saying that is happening here, <snip>

Following the line of the famous Mr. Comey, i´d say ...not with your words.... ;) (as the subtext could have..... :) )

As for DBT, it has been around a long, long time... Heck, even the "new" ABX test was around in the 1950's: "The history of ABX testing and naming dates back to 1950 in a paper published by two Bell Labs researchers, W. A. Munson and Mark B. Gardner, titled Standardizing Auditory Tests.[1]" -- Wikipedia. <snip>

I know. The history of "controlled blind tests" in psychophysics started even earlier, but my really innocent comment was related to the assessment of a multidimensional perception overall (music as stimuli). Usually psychoacoustic experiments were examining single parameters, beside rare events like the Olson experiment that i´ve mentioned. Therefore my surprise that it started already 10-12 years before Shanefield´s articles and not as a single event but as an ongoing/continuous reseach style.

@amirm,

Just for reference, ABX testing is older than that: <snip>

As said above, i know, therefore wrote in some threads that researchers already in the 1950s compared A/B-results to ABX-results and attributed the differences found to the different internal mental processes involved.
 
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Cosmik

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I know. The history of "controlled blind tests" in psychophysics started even earlier, but my really innocent comment was related to the assessment of a multidimensional perception overall (music as stimuli). Usually psychoacoustic experiments were examining single parameters, beside rare events like the Olson experiment that i´ve mentioned. Therefore my surprise that it started already 10-12 years before Shanefield´s articles and not as a single event but as an ongoing/continuous reseach style.
...
As said above, i know, therefore wrote in some threads that researchers already in the 1950s compared A/B-results to ABX-results and attributed the differences found to the different internal mental processes involved.
But for all that, a DAC is still a device designed to produce an output that is as close to linear as possible. Ditto an amp. And ditto a speaker. In other words, all the psychoacoustics in the world have hardly changed the audio system at all since the 1950s. All that has happened is that technology has allowed it to get a little closer to the same ideal.
 

tomelex

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Stereo, is well, stereo. Its not a natural conscript, nowhere in real life do you hear a "soundstage" from two spaced point sources as far as music goes. It is incapable of recreating the real event. In fact, it is possible that the more perfect a stereo system is, the less some folks like it. The thing is the recording is the big player in this game. Think of how you can listen to various recordings of the same song, the different mastering can make one song "sound right" on your system while the others don't, same system...playback, speakers, room....yet song sounds so much better. We are slaves to the recording, and all our gear can do is play it back. That's why there are tone controls and other things so you can tailor someone elses idea of what they thought you should hear to what you want to hear.

Testing a speaker for accurate reproduction makes sense. That means more differentiation of each song you play, and then, if you want, you can tone control the thing all you want if you feel the need to "tailor" the sound the way you want. We are in control, despite the high end idiot mags of the seventies taking away tone controls and switches and equalizers and all other things that I grew up with, that allowed me to find s "sound" I liked, and the more I am happy with the sound, the more I enjoy the experience.

Using speakers as tone controls, preamps, amps, speakers, interconnect and cables etc are the fools guide to audio perpetuated by the seventies mags has created the nightmare high end is in. Make each part of the process as perfect as possible, then let the customer choose his method of tone control to suit individual preference, if he wants to.
 

Jakob1863

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But for all that, a DAC is still a device designed to produce an output that is as close to linear as possible. Ditto an amp. And ditto a speaker. In other words, all the psychoacoustics in the world have hardly changed the audio system at all since the 1950s. All that has happened is that technology has allowed it to get a little closer to the same ideal.

In a sense, yes sort of "linear" is the goal, but wrt two channel stereo reproduction strict linearity overall seems not to be the right choice for most people. See for example todays target response curves for the "room correction systems" which resemble quite closely the Brüel & Kjaer preferred curve from around 1970 (afair).
So, at least for the listening position a strictly linear as possible reproduction isn´t approached.

Psychoacoustics only tries to find out what humans can hear (sometimes which way the listening sense works) and follows the more modern definition given by Jens Blauert who stated that psychoacoustic examines if a sound event or the difference between sound events can be perceived.
And, leaving aside the definition of the target for the moment, psychoacoustical experiments help often to find out which direction to go in development as long as the target is not yet reached......
 

oivavoi

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Just a general comment: interesting to read these comments from Toole. Really looking forward to the new edition his book. His work has been very important when it comes to making the audio world more rational. I do think, however, that he is not fully consistent in his approach. If listening tests are to be the final arbiter when it comes to quality, then he is wrong to dismiss room correction in the way he does, for example. I know of three published listening tests which looked at room correction (including one by Toole's former partner Sean Olive), and all of them found that at least some room correction products were preferred by the listeners when compared to uncorrected sound.

Of course, one might argue that the results in listening tests can be wrong - and in truth, three tests is not a very substantial body of work. But if you open up that can of worms, it becomes more dubious how far it will get you to base everything on listening tests.

In a way, its similar to focusing too much on focus groups in politics or product development. Focus groups would surely have indicated that politicians such as Trump and Corbyn never stood a chance of getting close to power. But we know how that turned out.

And how about a success such as the iPhone? Steve Jobs didn't believe in focus groups, he believed in giving people what they didn't even know they wanted. The whole Harman approach seems to me excel at perfecting middle of the road products that are not really disliked by anyone, but that aren't pushing the envelope either.
 

amirm

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Just a general comment: interesting to read these comments from Toole. Really looking forward to the new edition his book. His work has been very important when it comes to making the audio world more rational. I do think, however, that he is not fully consistent in his approach. If listening tests are to be the final arbiter when it comes to quality, then he is wrong to dismiss room correction in the way he does, for example. I know of three published listening tests which looked at room correction (including one by Toole's former partner Sean Olive), and all of them found that at least some room correction products were preferred by the listeners when compared to uncorrected sound.
Dr. Toole 100% believes in room correction for low frequencies. Indeed that is how his own system is running and he/harman consider it mandatory. As do I. :) Take his multi-sub recommendation. That configuration creates massive peaks in response which must be brought down with EQ.

Above transition frequencies, it is not that he is against it, but thinks people use it to correct for bad speakers that have poor off-axis response. His point is correct of course in that if you do anything upstream of the speaker, it acts on both direct and indirect sound. While this is true in theory, Dr. Olive's test that you mention did show a subjective improvement in correcting the directivity dip in B&W speakers.
 
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Blumlein 88

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In a sense, yes sort of "linear" is the goal, but wrt two channel stereo reproduction strict linearity overall seems not to be the right choice for most people. See for example todays target response curves for the "room correction systems" which resemble quite closely the Brüel & Kjaer preferred curve from around 1970 (afair).
So, at least for the listening position a strictly linear as possible reproduction isn´t approached.

Psychoacoustics only tries to find out what humans can hear (sometimes which way the listening sense works) and follows the more modern definition given by Jens Blauert who stated that psychoacoustic examines if a sound event or the difference between sound events can be perceived.
And, leaving aside the definition of the target for the moment, psychoacoustical experiments help often to find out which direction to go in development as long as the target is not yet reached......

You need to realize the reason the measured response of speakers should not be flat. It is due to measurement artefacts. You need a certain time window to obtain a certain level of frequency resolution. That means reflected energy is picked up more by the measurement as frequency increases. So in effect if you set your speaker to flat response measured, your actual response is up tilted. Target room response curves compensate for that effect. The B&K work from the 70's actually refers to this. The famous graph says, "Measured in the Actual Listening room".
 

Fitzcaraldo215

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If listening tests are to be the final arbiter when it comes to quality, then he is wrong to dismiss room correction in the way he does, for example. I know of three published listening tests which looked at room correction (including one by Toole's former partner Sean Olive), and all of them found that at least some room correction products were preferred by the listeners when compared to uncorrected sound.
Before I was aware of Toole or Olive's writings, I tried DSP Room EQ at home. The beautiful thing is it easily to rapidly switch on and off, blind even, for listening preference comparisons. That was 10 years ago. I would never, ever be without it. A fair number of my friends tried it, and all were just as convinced on a diverse choice of equipment. Actually, no one I know who has calibrated it properly in their room has not felt it was an improvement.

The only controversy seems to be whether to use it only in the bass below the transition frequency or to use it full range. In my circle, only one does not prefer full range EQ.

In some ways, this is a contemporary answer to @tomelex on tone controls. It is one which avoids some past negative side effects with tone controls, particularly when applied in the analog domain. While most EQ tools do not make it easy to manipulate the response on the fly, some like Dirac, allow rapid selection of one of 4 prebuilt response profiles. So, it can be both room EQ and frequency compensation for program material if desired.
 

Cosmik

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Could someone please define "linear"?
The way I mean it is "Straight wire with gain" i.e. what goes in comes out at the other end the same, including the phase and timing.

This differs from most people's idea of a hi-fi system which is something that reproduces the frequency components in the desired proportions (with no extra components or it definitely wouldn't be linear), but is allowed to shuffle around the phase, and timing of when they appear.
 

The Smokester

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The way I mean it is "Straight wire with gain" i.e. what goes in comes out at the other end the same, including the phase and timing...

If that is what is meant, then I don't understand this at all:

In a sense, yes sort of "linear" is the goal, but wrt two channel stereo reproduction strict linearity overall seems not to be the right choice for most people. See for example todays target response curves for the "room correction systems" which resemble quite closely the Brüel & Kjaer preferred curve from around 1970 (afair)...
 

amirm

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Could someone please define "linear"?
Linear means total absence of distortion.

Of note, room impact on the sound of the speakers is 100% linear (sans rattles and such). In other words, the room does not add any distortion products.

In the context here, we are talking about the shape of the frequency response. That can be flat, smooth or both. Listening tests show that what is important is smoothness (i.e. lack of variations). Flat response is not preferred. And at any rate, being flat has nothing to do with a system being linear.
 

tomelex

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One reason a perfect linear output from your speaker can not be "calibrated" when playing music is the hearing curves....not knowing how loud the mix and master engineer were listening to the music when they were deciding what you would like, if you play back at a lower volume, the music will not have enough bass, or upper highs. There just is no standard from mix/master to you. Its all a slippery slope in audio.
 

Blumlein 88

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One reason a perfect linear output from your speaker can not be "calibrated" when playing music is the hearing curves....not knowing how loud the mix and master engineer were listening to the music when they were deciding what you would like, if you play back at a lower volume, the music will not have enough bass, or upper highs. There just is no standard from mix/master to you. Its all a slippery slope in audio.

Or as Toole calls it: the circle of confusion.

Your recording is your reference which based upon how it sounds on playback. Playback is your reference based upon the recording.
 
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