Floyd Toole: Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms (AES Presents) 3rd Edition - Discussion Thread

[Sonnie Parker]

This will be a discussion thread about this book... but before we get into that, I am curious where most people are buying this electronically. I see it on Amazon, but I don't have a Kindle reader. I will be using a laptop, and Kindle for the PC is shamed pretty bad by reviewers. I've read the first chapter and part of the second via Google Books, and it seems okay there, and it's $53 there. Perhaps that's the going price, as it is $47 on Amazon.

So about the book thus far. Wow... I can see a LOT of naysayers in regards to this book. Toole seems to go against what appears to me to be the mainstream thought process of comparing audio equipment. No doubt he has ruffled some feathers. However, I've not seen any of it yet, because I have probably ignored it or just haven't been in the right places to read negative comments about it. As of right now, I've only seen very positive comments about it.

A few comments I see that could stir up a hornets nest... and you really can't mistake these for being taken out of context. They are very likely related to exactly what you would think they are in most cases. In some cases, more context is probably helpful to see the bigger picture, but not mandatory. If you want to know more... buy the book.

Electronic devices, analog and digital, are also in the signal paths, but it is not difficult to demonstrate that in competently designed products, any effects they may have are small if they are not driven into gross distortion or clipping. In fact, their effects are usually vanishingly small compared to the electro-acoustical and acoustical factors. Tests of these effects quickly become exercises in “is there or is there not any difference?” This was the origin of the well-known ABX test, which has shown with monotonous regularity that well-designed power amplifiers, loudspeaker wires and the like are not responsible for offensive sounds. Occasionally a test may show that a difference was observed at a level of statistical significance. This is of importance only if the observers can state a preference—which one is more real or more accurate? It is human nature to think that hearing any difference is associated with an improvement, which is a reason that A vs. B tests need to be randomly balanced with B vs. A tests. Conducting meaningful listening tests is a science unto itself (see Chapter 3).

Some audio journalists are hostile to the very notion that audio is amenable to scientific investigation—asserting that only subjective opinion, preferably theirs, matters.

The presumption implicit in this illustration is that it is possible to create measurements that can describe or predict how listeners might react to sounds produced by the device being tested. There was a time when this presumption seemed improbable, and even now some people claim that we cannot measure what we hear. The reality is that with research and the development of newer and better measure ment tools, it has been possible to move the hands of the “doomsday clock” to the point where detonation is imminent. In fact, it would be correct to say that the explosion has begun. Some aspects of audible sound are now more reliably revealed by technical data than by the normal kinds of subjective evaluations.

Many of the variations in recordings take forms that can be addressed by old fashioned bass and treble tone controls. Unfortunately, tone controls are frowned upon by audio purists, who think that they somehow degrade the performance.

We need to be more realistic, acknowledging that “loudspeaker” music is not the same as live music. There are fundamental similarities to be sure, but there are also gross differences. No magic wire, loudspeaker stand or spike, power line filter or trinket on a wall will make it right.

This was the origin of the well-known ABX test, which has shown with monotonous regularity that well-designed power amplifiers, loudspeaker wires and the like are not responsible for offensive sounds. Occasionally a test may show that a difference was observed at a level of statistical significance. This is of importance only if the observers can state a preference—which one is more real or more accurate? It is human nature to think that hearing any difference is associated with an improvement, which is a reason that A vs. B tests need to be randomly balanced with B vs. A tests.

I have noticed this effect when I return home after a trip. I turn my system on and it may sound a little “different.” It doesn’t last long, and in a few minutes I am back in the familiar context. Nothing has “broken in”; it was me readapting. This is the common situation of product reviewers noting differences in sound of a new product introduced into their listening room, but over time adapting to its characteristics. Apart from tiny changes in woofer resonance frequency, loudspeakers do not “break in”—that is a physical fact—but listeners certainly do.

In parts of the audio industry there is a belief that all components − wires, electronics and loudspeakers − need to “break in.” Out of the box, it is assumed that they will not be performing at their best. Proponents vehemently deny that this process has anything to do with adaptation, writing extensively about changes in performance that they claim are easily audible in several aspects of device performance. Yet, the author is not aware of any controlled test in which any consequential audible differences were found, even in loudspeakers, where there would seem to be some opportunities for material changes.

In audio there are numerous parallel examples of listeners hearing qualities in sounds that are not, or simply cannot, be there. If one believes that there will be a differ ence, there very likely will be a difference. The sound waves impinging on the eardrums have not changed, but the perceptual process of the brain has decided that there is a difference. Double-blind tests may show that there is no difference, but such is the strength of belief that some people argue that it is the test that is at fault, not the reality that no change in sound existed. Some audio journalists promote these ideas, and products possessing these mystical powers come and go.

Audio journalism is a business, with income, expenses, writers and reviewers to be paid, advertisers to be found and satisfied, and next month’s issue to be prepared. Consequently, there are compromises, most of them understandable. Product reviews are a big attraction for readers, but most often there are limited or no proper measurement facilities, measurements or data analysis, no dedicated venues for controlled double-blind listening, and loudness-controlled comparisons. With such little opportunity to conduct meaningful subjective and objective evaluations, the usual result is pages of articulate, often highly literate and colorful prose—opinions. When challenged to produce validation for those opinions, there is pushback.

Layered over all opinions is a “fog” of uncertainty related to the mostly imagined influence of wires, power cords and conditioners, spikes and numerous other audiophile beliefs.

Just a very small sampling of comments I see argued over significantly.

I am not suggesting everyone else is necessarily right or wrong here... just posting it up for discussion. Obviously we all decide for ourselves who and what we want to trust for information sources and we can make our own justifications based on the writer's credentials and/or whatever else we choose to use as justification.

 

[what bass]

Being a novice in audio, forget the high end descriptor, I hesitate to debate much written by a man who clearly has status in the audio world over myself. That being said, I find the book thus far to be an easily understood guide through my self induced mysticism of audio reproduction.

I certainly look forward to following this thread as I continue through the remainder of the book.

 

[SRW1000]

I bought the Kindle version back in 2017 and it was $47.36 at that time. What helped is that Amazon was still giving out tons of digital credits if you selected the slower shipping option, so it only cost me $24.14. They still offer those, but on anywhere near as many items as they did back then, thanks to Covid.

I had been watching the price for a long time, and don't believe I ever saw a better price for it. Maybe that's because it's considered a textbook?

I've read it exclusively on my laptop using the PC Kindle program and haven't noticed any issues. I haven't looked at any reviews for the PC version of Kindle, but maybe ignorance is bliss.

 

[Sonnie Parker]

I certainly don't have the knowledge or the credentials to argue with him. What I have read thus far seems to be pretty much what my experiences are with regards to comparisons in equipment and that speakers are the largest factor in what makes a difference in a room.

Certainly I have not seen every comment made in reference to his writings, but I can guarantee you if a regular guy like me or many of us here posted some of his same statements in my first post, we would get hammered in some places. Maybe no one is going to challenge him because they have no evidence to support their challenge outside of subjective listening. Then again, there may be challenges out there that I've just not seen.

I have zero experience with production or reproduction. I have been to many many concerts (was a ticket broker for several years), but not like the concerts Toole as been to. I've been to countless amphitheaters, coliseums, civic centers, football stadiums, etc... and sat dead center from front row on back for many of those. However, they are not custom built and treated symphony halls, so I can't say there would be very many similarities in comparison. What I do know is I actually prefer the sound in my room over the sound of concerts. I enjoyed the concerts I attended, but there was too much other noise going on to enjoy the sound quality that may or may not have accompanied. I believe I can agree with Toole in that I have "adapted" to the sound I hear in my room and therefore like it best.

 

[SRW1000]

It is worth mentioning that Dr. Toole and his publisher have published some supplemental material that can be downloaded for free from their website:

https://routledgetextbooks.com/textbooks/9781138921368/home-theatre.php

It's a great way to get a taste of Toole's thoughts on the practical aspect of room design, and may be enough of a taste for readers to determine whether or not is worth buying the full text book. For a free resource, it's actually pretty dense with useable info.

Scott

 

[Sonnie Parker]

It is not a mystery that knowledge of the products being evaluated is a powerful source of psychological bias. In comparison tests of many kinds, especially in wine tasting and drug testing, considerable effort is expended to ensure the anonymity of the devices or substances being evaluated. If the mind thinks that something is real, the appropriate perceptions or bodily reactions can follow. In audio, many otherwise serious people persist in the belief that they can ignore such non-auditory factors as price, size, brand and so on.

I could be guilty.

 

[Kal Rubinson]

I could be guilty.

We are all guilty.

 

[JStewart]

This one quote from Dr. Toole is the reason for most of the debate and the opportunity for the charlatans to take advantage:

“In audio there are numerous parallel examples of listeners hearing qualities in sounds that are not, or simply cannot, be there. If one believes that there will be a difference, there very likely will be a difference. The sound waves impinging on the eardrums have not changed, but the perceptual process of the brain has decided that there is a difference.”

 

[Marc Lombardi]

One thing to be very conscious of is the specific test conditions and conclusions - as well as EXclusions - in areas that tend to be controversial. If someone disagrees with him, they bear the burden of proof to at least the same degree of scientific rigor as he put into his research. Just about NOBODY does this.
In a sense, Toole may not be 100% right, but he's unlikely to be wrong

 

[AJ Soundfield]

I could be guilty.

I developed my own vaccine and self immunized.

 

[mechtheist]

It never ceases to amaze me how some folks simply refuse to believe that human beings are NOT objective, precision instruments. It's noteworthy that Toole said "shown with monotonous regularity ", these issues are settled. They've known for something like 7 decades that if you want reliable results in drug tests you have to go to double blind testing. Think about the implications of that. Try. Our ears are not microphones, our eyes are not cameras, what you perceive is a creation of the brain and is in no way some kind of simple mapping or linear recording of sensory inputs. Search for Dan Ariely or David Eagleman videos, after watching a few of these, you can get an idea of how profoundly our perceptions are influenced, driven might be more accurate, by all kinds of crap going on in our minds, often mundane crap. It's foolish to believe you can be objective in these things, you simply can't, not if you're a human being.

 

[Marc Lombardi]

... on the other hand, ignorance is bliss ... I envy the person who can put his $2000 speaker cables on wooden blocks and think they sound better

 

[BenToronto]

Even if you know the earlier edition (there was only one, as Toole explains), this one is substantially richer and better. If you want to think of yourself as an educated audiophile , you can't neglect this book.

The largest theme arc of the book actually addresses the "Can you measure quality" debate. And Toole's answer is the spinorama.

The most provocative conjecture to some readers is that (a) surprising number of pro and amateur listeners have developed hearing defects, (b) conventional hearing testing oriented to speech does not measure it too well, and (3) even those who think their hearing is perfect are really quite deficient in their sensitivity.... and I would add, are too arrogant to know it it is crapping up.

Which leads to the famous Circle of Confusion but with a recording engineer and producer with poor hearing in the circle. Which leads to Toole repeated suggestion of using old fashioned tone controls (or a one-knob timbre control) for any recording that needs it.

Also hinted at is the argument that it is mistaken to think (or to want to) correct your room , like with REW that I keep permanently ready in my music room. The room is the room and you can't make it go away hoping to bring Carnegie Hall in instead. You can EQ the speakers and then, I suppose, you can bring in the recording engineer's workroom (or their earbuds). Does Uncle Jack sound different in you kitchen versus on the sidewalk?

Toole is a PhD physicist who has tried to walk the line between acoustics and perception. As a human factors psychologist, I feel better when people with my kind of training do acoustics than when people with his kind of training try to do psychology. Maybe just me.

 

[Marc Lombardi]

Not that he would in any way compromise science, but Toole was essentially paid to help Harman sell speakers. So the spinorama, etc. were aimed at being able to predict from measurements which speaker people would like. Nothing wrong with that, for sure. But it may or may not result in a speaker that accurately reproduces sound. It did seem to result in speakers that had qualities that listeners liked in the listening room, that could not directly be measured. For example, a speaker that has flat response and uniform dispersion in the spinorama correlates to a speaker that people like to listen to in the listening room, albeit with different measured response and subjective qualities in the listening room compared to the spinorama.

In the listening room people like the sound to rise slightly in the bass and droop slightly in the treble. That was determined in a series of controlled studies with specific conditions. Does that mean I should strive for a similar response in my room? Do those study conditions correlate well to my room? Should I do as so many people do ... tweak REW or Dirac or Audyssey to try to reproduce the legendary "Harman Curves"? I've looked pretty hard and I think the only references indicate that Toole has said we should NOT do that.

 

[BenToronto]

I don't recall ever reading about the training Toole imposes on his listeners, that is, what are they listening for. Nor do I know (or ever like) the mostly female pop singers in prolly over-cooked recordings he feels are discriminating stimuli.

But in data starting long before Harman, he presents evidence of uniformity of judgment and other interior evidence to trust his panels.

Puzzling to me just how good listeners could pooh-pooh electrostatic speakers (which seem to always test poorly with Toole), beats me, (and I suspect he is puzzled too).

Apropos house curve, strange to me why the bass boost doesn't look larger, more like the dramatic Fletcher-Munson's. As for treble cut he advocates, perhaps speaks to the weak-treble beloved by those using tube amps and who diss'ed CD players at first because they didn't hide some too-close-to-the-mic sound which is unnatural but prized by other audiophiles.

 

[Kal Rubinson]

I developed my own vaccine and self immunized.

But we are still too far from herd immunity.

 

[Marc Lombardi]

But we are still too far from herd immunity.

"Heard" immunity?

 

[Kal Rubinson]

Does Uncle Jack sound different in you kitchen versus on the sidewalk?

Actually, yes but no one pays attention to it. You only go so far as to recognize the characteristics that allow you to identify him as Uncle Jack (or Uncle Jack with a sore throat). I did some ad hoc testing after installing decent acoustical treatment in my CT audio room.by asking guests (audiophiles and others) to pay attention to my voice as we walked from room to room while I kept talking. Everyone noted how much clearer my voice was and how it stood apart from the rest of the noise when we entered that particular room.

 

[Marc Lombardi]

Harman How to Listen

A blog for users of the listener training software application "How to Listen."

harmanhowtolisten.blogspot.com

I haven't done this. Maybe now that I'm retired.

 

[BenToronto]

Thanks very much for link to listener training.

These days I am really going bananas with annoyance over the broadcast sound distortion due to all the humans (esp PBS news) using earbud and laptop mikes, and poor transmission from home, and not to mention masks. Horrid sound.

 

[Marc Lombardi]

Thanks very much for link to listener training.

These days I am really going bananas with annoyance over the broadcast sound distortion due to all the humans (esp PBS news) using earbud and laptop mikes, and poor transmission from home, and not to mention masks. Horrid sound.

It was a little quirky to get running but I figured it out. Did about 20 or so trials. I don't know what happens throughout the whole thing but at the beginning it has you identify which of a number of bands of EQ boost is applied. I did pretty well until it got up to six choices ... than I decided to listen to my own music for a while.

 

[Sal1950]

So about the book thus far. Wow... I can see a LOT of naysayers in regards to this book. Toole seems to go against what appears to me to be the mainstream thought process of comparing audio equipment. No doubt he has ruffled some feathers. However, I've not seen any of it yet, because I have probably ignored it or just haven't been in the right places to read negative comments about it. As of right now, I've only seen very positive comments about it.

If you believe in Santa Claus, Peter Pan, and the Tooth Fairy, you might get discouraged by Floyd's book as it doesn't encourage flights of fancy. Audible claims need to be supported by hard repeatable evidence, not "I heard it, so it is so".
BTW, will there be a movie and when might it be released?

 

[w_sizer]

I do not have a technical background, but I have been in the audiophile game for better than 35 years. Generally speaking, it's been my experience that guys like Dr. Toole, Brent Butterworth, the late Julian Hirsch, etc. (i.e., the science-based crowd) are correct with regard to the sound of line level components. Hirsch once stated in a feature article in Stereo Review that the three main determinants of the sound of a system are the speakers, the room acoustics, and the quality of the recording; everything else pales in importance. I am amused when I see self-designated golden-eared reviewers blithely attributing all manner of colorful sonic characteristics to amplifiers whose noise and distortion levels are orders of magnitude below the limit of human hearing and whose frequency responses are essentially flat. Simply put, if sonic differences exist between these technological devices, they should be measurable and/or explainable in technical terms.

Now that my official opinion is out of the way, it's time to contradict myself (sort of). About 30 years ago, I got rid of a Yamaha CD player with so-called "floating bit" technology (it broke) and replaced it with a Sony that cost substantially less. Being a loyal reader of Stereo Review and other science-based publications, I expected to hear basically no sonic difference between the two CD players. But imagine my surprise when I started hearing micro-details that I had never before noticed and timbral accuracy that seemed to be significantly improved with the Sony in the system. Perhaps there was some weird psychological factor at play or a subconscious expectation that the Sony would sound better in spite of my conscious convictions, but I'm not so sure, since it was a much cheaper unit. In any event, I have since chalked it up to the fact that those were early days for CD players, and there may have been some technologies (like "floating bit") back then that simply flopped. I think Yamaha abandoned it pretty quickly. Still, I wonder...

 

[Sal1950]

But imagine my surprise when I started hearing micro-details that I had never before noticed and timbral accuracy that seemed to be significantly improved with the Sony in the system. Perhaps there was some weird psychological factor at play or a subconscious expectation that the Sony would sound better in spite of my conscious convictions,

Happens quite often, you have a new piece of gear and your listening more closely trying to determine its sound quality and you start to hear some details you've missed before during more relaxed times.
Cheers,

 

[JonPike]

Happens quite often, you have a new piece of gear and your listening more closely trying to determine its sound quality and you start to hear some details you've missed before during more relaxed times.
Cheers,

Heh, entirely likely effect in that scenario, of course.. Now, you two, come up with an experimental test method to eliminate or minimize the test subject's "closer attention effect" with two, serially listened to pieces of equipment. Assume there might be an actual effect, besides the possible psycoacoustic effect.

More of a challenge than it at first seems, when you think about it, yes?

It's not easy, this testing stuff...