I cannot trust the Harman speaker preference score

[Duke]

Anthony has also mentioned at least in one video discussion that he sometimes likes the RT to rise just a little bit in the HF. Does that kind of talk also make no sense?

The idea might be to offset the radiation pattern narrowing in the top octave which is typical of conventional loudspeakers.

 

[Vuki]

It isn't often that I see measurements where I am almost certain I will not be happy to experience it in person even with eyes closed and distracted listening to most music...

But this might be one:

View attachment 192870

Doesn't matter if this were a Genelec One speaker if the RTx looked like this:

View attachment 192872


Few more frequency-time graph views:

View attachment 192873 View attachment 192874 View attachment 192875 View attachment 192880 View attachment 192887

Was that in the big ceramic tiled room?

 

[Floyd Toole]

Late to the party, but here anyway . . .

As you might have imagined, I have been lurking and reading this somewhat confused, but interesting, thread for some time. I told Sean Olive about it, and he has jumped in with numerous substantive comments. He has dealt with many of the issues I felt compelled to respond to, but the subjective/objective correlation work was his and the initial challenge was to the rating itself. So, he is the first-responder authority on the topic.

This somewhat rambling response is based on writings that may eventually make their way to the companion website for my book (www.routledge.com/cw/toole). For the present purpose the document has grown overly long, so I will attach it as a pdf file for download. It is intended to expand on some of the discussion topics from perspectives that I thought were missed. I will refer to figures in my current book: “Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms”, 3rd edition, Focal Press 2017.

 

[ROOSKIE]

Late to the party, but here anyway . . .

As you might have imagined, I have been lurking and reading this somewhat confused, but interesting, thread for some time. I told Sean Olive about it, and he has jumped in with numerous substantive comments. He has dealt with many of the issues I felt compelled to respond to, but the subjective/objective correlation work was his and the initial challenge was to the rating itself. So, he is the first-responder authority on the topic.

This somewhat rambling response is based on writings that may eventually make their way to the companion website for my book (www.routledge.com/cw/toole). For the present purpose the document has grown overly long, so I will attach it as a pdf file for download. It is intended to expand on some of the discussion topics from perspectives that I thought were missed. I will refer to figures in my current book: “Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms”, 3rd edition, Focal Press 2017.

Seems totally appropriate to me that while you were replying to this thread I was watching the Obi Wan Kinobi (my favorite character) trailer linked from that discussion elsewhere on ASR.
Awesome! Excited to read your essay.

 

[HooStat]

The combined direct sounds from L and R loudspeakers acoustically interfere at the ears to generate an octave wide cancellation dip around 2 kHz for the listener in the sweet spot – an audible timbral error that is a permanent feature of stereo

I was fascinated by this quote from the @Floyd Toole essay. Does this imply that a mild bump in level around 2 kHz would be beneficial for the person in the sweet spot for stereo listening? Or, alternatively, a dip in this area might be a little worse than the frequency response might imply?

 

[Floyd Toole]

I was fascinated by this quote from the @Floyd Toole essay. Does this imply that a mild bump in level around 2 kHz would be beneficial for the person in the sweet spot for stereo listening? Or, alternatively, a dip in this area might be a little worse than the frequency response might imply?

The problem is that it is due to destructive acoustical interference - not exactly correctable with EQ. Besides, it audibly changes with tiny changes in position each side of the sweet spot. One can play mono pink noise and find the sweet spot exactly by listening for the amount of dullness. The more dominant the direct sound the more obvious is the effect. So, close-up listening or attenuated reflections make the problem worse.

 

[Shazb0t]

Late to the party, but here anyway . . .

As you might have imagined, I have been lurking and reading this somewhat confused, but interesting, thread for some time. I told Sean Olive about it, and he has jumped in with numerous substantive comments. He has dealt with many of the issues I felt compelled to respond to, but the subjective/objective correlation work was his and the initial challenge was to the rating itself. So, he is the first-responder authority on the topic.

This somewhat rambling response is based on writings that may eventually make their way to the companion website for my book (www.routledge.com/cw/toole). For the present purpose the document has grown overly long, so I will attach it as a pdf file for download. It is intended to expand on some of the discussion topics from perspectives that I thought were missed. I will refer to figures in my current book: “Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms”, 3rd edition, Focal Press 2017.

Very enjoyable read! Illuminating on the downsides of stereo loudspeaker comparison vs mono. Thank you for sharing.

 

[Floyd Toole]

The problem is that it is due to destructive acoustical interference - not exactly correctable with EQ. Besides, it audibly changes with tiny changes in position each side of the sweet spot. One can play mono pink noise and find the sweet spot exactly by listening for the amount of dullness. The more dominant the direct sound the more obvious is the effect. So, close-up listening or attenuated reflections make the problem worse.

I can add that because of the double-mono soundstage and the consequent acoustical interference at each ear any thoughts of phase integrity in the direct or any other sounds arriving at the ears are off the table.

 

[CtheArgie]

Dear Dr Toole @Floyd Toole. Thanks for the great summary!

I have one tiny bone to pick with you. We go to Disney Hall probably 6 to 10 times a years. We don't find the acoustics of the hall particularly good. Specifically, we find bass sounds very muted. I remember a few years ago we went to the entire Beethoven Symphonies in order in three days. The 9th sounded really anemic. It may be the seats we have.

We only found that the Saint Säens Third excited the room. Plus Cameron Carpenter's organ.

Interestingly, we think that the Hollywood Bowl has a more "balanced" sound (from where we seat right behind the sound engineers). Of course, it is a completely different setting. Forget about direct sound, it is all PA sound.

PS: I used to live in NJ and got used to Carnegie Hall, which has a "warmer" sound. But even the theatre in Santa Barbara, the auditorium in Northridge (Cal State) and the TO hall seem to have beer acoustics. But what do I know????

Maybe @Sean Olive, who seems to be my neighbor up the road will share his perspective.

 

[Floyd Toole]

Dear Dr Toole @Floyd Toole. Thanks for the great summary!

I have one tiny bone to pick with you. We go to Disney Hall probably 6 to 10 times a years. We don't find the acoustics of the hall particularly good. Specifically, we find bass sounds very muted. I remember a few years ago we went to the entire Beethoven Symphonies in order in three days. The 9th sounded really anemic. It may be the seats we have.

We only found that the Saint Säens Third excited the room. Plus Cameron Carpenter's organ.

Interestingly, we think that the Hollywood Bowl has a more "balanced" sound (from where we seat right behind the sound engineers). Of course, it is a completely different setting. Forget about direct sound, it is all PA sound.

PS: I used to live in NJ and got used to Carnegie Hall, which has a "warmer" sound. But even the theatre in Santa Barbara, the auditorium in Northridge (Cal State) and the TO hall seem to have beer acoustics. But what do I know????

Maybe @Sean Olive, who seems to be my neighbor up the road will share his perspective.

It seems we three are all neighbors - I live in Sutton Valley too, and Sean has gone with me to several Disney Hall concerts. The organ is indeed a delight, as heard from the front row where I last sat - close to the "action". My current regular seats are in row G of the front stalls and the orchestra sounds pretty darn good from there. Bass muted - not to my ears, but we are different people in different seats. One has to be aware of the seat-dip effect (upper bass attenuation), which is different for different locations - a reason to sample different seats. I have regarded some performances as being absolutely reference quality. FYI I may be an outlier, not having been overwhelmed by the Vienna Musicverein. I'm not a fan of classical music through a PA, although I have enjoyed the Bowl a few times for popular stuff. That said, I walked out of a couple of concerts because of crappy sound (totally due to the front-of-house person), sat in my car opened the windows and played higher quality music for ourselves and a few bystanders - trapped in the parking lot until the concert ended. One only lives life once and bad sound and bad wine are inexcusable, right?
Glad you enjoyed the summary.

 

[CtheArgie]

It seems we three are all neighbors - I live in Sutton Valley too, and Sean has gone with me to several Disney Hall concerts. The organ is indeed a delight, as heard from the front row where I last sat - close to the "action". My current regular seats are in row G of the front stalls and the orchestra sounds pretty darn good from there. Bass muted - not to my ears, but we are different people in different seats. One has to be aware of the seat-dip effect (upper bass attenuation), which is different for different locations - a reason to sample different seats. I have regarded some performances as being absolutely reference quality. FYI I may be an outlier, not having been overwhelmed by the Vienna Musicverein. I'm not a fan of classical music through a PA, although I have enjoyed the Bowl a few times for popular stuff. That said, I walked out of a couple of concerts because of crappy sound (totally due to the front-of-house person), sat in my car opened the windows and played higher quality music for ourselves and a few bystanders - trapped in the parking lot until the concert ended. One only lives life once and bad sound and bad wine are inexcusable, right?
Glad you enjoyed the summary.

Thanks for the kind answer and comment. We live in Agoura Hills very near the burnt down Peter Strauss ranch.

Our Disney seats tend to be further away. Maybe half way up. Trust me, no good bass there. We recently had excellent tickets in the first rows but the pandemic cancelled it at the last moment. It’s like real estate, location, location, location!

I agree the Bowl can be mixed, but when the Dude conducts he gets great sound from where we are. The engineer told me once that the Dude does some listening near him during some rehearsals and adjusts the sound accordingly. But the Bowl is mostly social for us. A few seats have had the same people for a few years and we get to chat and picnic before the concert with them.

No matter where, the Dude has given us amazing music over the years!

I laughed with Sean that we’ll one day bump into each other at the Kanan CVS.

 

[MattHooper]

Maybe this quote from Toole's "Loudspeakers and Rooms" will help you see the light:

“In-head localization seems like the logical opposite of an enveloping, external, and spacious auditory illusion. Perceptions of sounds originating inside the head, which routinely occur in headphone listening, can also occur in loudspeaker listening when the direct sound is not supported by the right amount and kind of reflected sound. The author and his colleagues have experienced the phenomenon many times when listening to stereo recordings in an anechoic chamber, usually with acoustically “dry” sounds hard panned to center or, less often, to the sides. It prompted an investigation (Toole, 1970), the conclusion of which was that there is a continuum of localization experience from external at a distance through to totally within the head. It is often noted with higher frequencies, and it can happen in a normal room with loudspeakers that have high directivity or in any situation where a strong direct sound is heard without appropriate reflections. Moulton (1995) noted that “speakers with narrow high-frequency dispersion . . . tend to project the phantom at or in front of the lateral speaker plane.” In an anechoic chamber, it can occur when listening to a single loudspeaker, especially on the frontal axis, in which case front-back reversals are also frequent occurrences. This phenomenon is so strong that it need not be a “blind” situation. Interestingly, a demonstration of four-loudspeaker Ambisonic recordings played in an anechoic chamber yielded an auditory impression that was almost totally within the head. This was a great disappointment to the gathered enthusiasts, all of whom anticipated an approximation of perfection. It suggested that, psychoacoustically, something fundamentally important was not being captured or communicated to the ears. An identical setup in a normally reflective room sounded far more realistic, even though the room reflections were a substantial corruption of the encoded sounds arriving at the ears.”

^^^ this is one of the reasons why I've debated the idea that "all we want to do is reproduce the recorded signal as accurately as possible."
I just don't think that captures what many of us are really looking for, and what is underlying the whole hi-fi project. We are generally seeking "good sound" which I'd say is some combination of, or continuum between "pleasing --- natural/realistic." Essentially all of the "problems" noted above had to do with subjective disappointments in that area. Presumably, for instance, the Ambisonic recordings scenario was carefully set up to reproduce the signal "accurately" and in the anechoic chamber that's all they heard. Yet this proved "disappointing" to the enthusiasts. The goal is suggested in the following sentence "An identical setup in a normally reflective room sounded far more realistic, even though the room reflections were a substantial corruption of the encoded sounds arriving at the ears.”

And of course much of the great Dr. Toole and Dr. Olive's research was centered around evaluating preferences, not "accuracy" per se (in other words, though a generally neutral tonality is preferred, this is in service to listening preference, what sounds "natural" and "pleasing," and if adding some level of reflections serve that purpose, even if they are "added to the recording signal" they can be considered a Good Thing. It's why this paen to accuractly reproducing the signal is a fairly slippery subject).

 

[hardisj]

^^^ this is one of the reasons why I've debated the idea that "all we want to do is reproduce the recorded signal as accurately as possible."

I still think that should be the *goal*. But with the benefit that when a speaker is designed with this in mind, it should lend itself to being easily EQ'd to taste/preference.

This is in regards to response linearity (on and off-axis). I still don't know yet if the general consensus is to prefer a flat or increasing DI (and, if the latter, how much). I have some white papers to read on that.

Anecdotally, I'm not sure flat is ideal; at least not with a flat on-axis response. Mainly in the treble. My listening and comparison to data tends to find most speakers that do exhibit flat DI do so in the treble region and when this is the case you wind up with a sloping in-room response until the treble region where it flattens out. This tends to sound "bright". Note, however, this is not the same thing as flat DI from 20-20kHz.

Personally, it seems I enjoy speakers that have a wider dispersion but a slightly increasing ERDI. This is based on purely sighted listening and comparison with the data. If I were to take a round of blind tests with a variable DI speaker (such as the Lexicon SL-1, shown below) I might find that to be different. That's the stuff that interests me the most right now.

 

[MattHooper]

Late to the party, but here anyway . . .

As you might have imagined, I have been lurking and reading this somewhat confused, but interesting, thread for some time. I told Sean Olive about it, and he has jumped in with numerous substantive comments. He has dealt with many of the issues I felt compelled to respond to, but the subjective/objective correlation work was his and the initial challenge was to the rating itself. So, he is the first-responder authority on the topic.

This somewhat rambling response is based on writings that may eventually make their way to the companion website for my book (www.routledge.com/cw/toole). For the present purpose the document has grown overly long, so I will attach it as a pdf file for download. It is intended to expand on some of the discussion topics from perspectives that I thought were missed. I will refer to figures in my current book: “Sound Reproduction: The Acoustics and Psychoacoustics of Loudspeakers and Rooms”, 3rd edition, Focal Press 2017.

I just want to say thanks for taking the time to write that!

Informative as always.

It's such a pleasure to take in the writing of an excellent communicator with such a keen grasp of the subject.

It really is a case where clarity of thought leads to clarity of prose.

 

[MattHooper]

I still think that should be the *goal*. But with the benefit that when a speaker is designed with this in mind, it should lend itself to being easily EQ'd to taste/preference.

Yes understood, but I always want to ask "to what end?" and the answer would still seem to be the goal I described (pleasant/natural/realistic sound).

Personally, it seems I enjoy speakers that have a wider dispersion but a slightly increasing ERDI.

I've found I can enjoy some directional speakers, tonally. But my main issue tends to be they feel less "natural" and too finicky for me.

I liken it to the analogy of when I used to go shopping for TVs when LCDs and rear projection TVs and Plasmas were batting it out in the box stores. LCDs (and rear projection) could look quite nice so long as I was directly in front of the screen, but as soon as I shifted my position at all off axis I'd notice the shift in image quality - the contrast going down, the color saturation depleting. It felt "shifty" - the illusion too delicate and fleeting (similar to those holograms you have to see only from just the right angle). Plasma being an emissive display had better viewing angles and felt "more natural" and "less finicky," - the image didn't obviously alter if I shifted my position, and I could admire the image more like I'd admire a painting, from any angle.

The same thing bugs me about really directional speakers. I know that stereo is an illusion, but it's just easier to sink in to it, and seems more natural and less finicky if I don't notice obvious shifts in tonal quality or imaging if I move my head much. So I've tended to favor for my own system speakers that seem to "disappear" well and sound very similar tonally if I stray off axis.

(My friend has some speakers right now that use 3 tweeters in a sort-of-line-array effect. The horizontal dispersion is quite good, but the vertical dispersion is very constricted and the speakers become very dull sounding as soon as I get up from the sofa. Even that bugs me).

 

[Holmz]

…
I've found I can enjoy some directional speakers, tonally. But my main issue tends to be they feel less "natural" and too finicky for me.
…

A narrower dispersion, or near field listening, woudl both be areas were the Olive score becomes deweighted… because there is less energy spewing out to the side to worry about its tonality in the first place.

Sounds like you and Erin both are attracted to speakers which are radiating wider, and then the O-Score gains importance.

I have historically used narrow dispersion, but that was more chance… but they seemed less room sensitive, so it was easier to not concern myself too much if the Haus-boss wanted a bare wood floor over carpet.

 

[Vuki]

@Floyd Toole thank you for joining. In your book there is figure 7.16 where spatial ratings was found to be highly program related. I doubt that found preferences hadn't reflected to sound quality preferences, but I couldn't find such results. Do you have any?

Also in Room effects test is said that loudspeakers with similar directivities and similary good performance were used. Of course that different rooms hadn't make much difference - loudspeakers were similar. But IMO it is quite possible that if loudspeakers with different qualities (not similar) were used the results would be different.

 

[fineMen]

I don't think there is any Harman-standard for sound production.

What I was trying to say here, was that removing reflections increases sense of space, contrary to what is easy to believe.

I'm also referring to comment #846

and to

... There are a lot of microphones at hand but classical orchestras often recorded at most with a dozen microphones.

I personally think that the ever persisting notion of an "original" encapsulated in the recording, to be revealed only by "better" gear, is proven wrong. It is an "audiophile" myth, and just keeps people on a desperate hunt. To no avail, though.

Regarding the "Harman Standard", I personally think that the de-facto standard is the most prominent merit of both, spinorama and Olive's score. So much so, that I happily neglect all the critique targeting these (@Dr. Sean Olive). After so many decades it was a big leap for the industry to agree on common grounds for designing the recording @studio and play back @home.

Regarding reflections it was (kind of) scientifically proven, that their absence/presence is a matter of taste, not quality. And for sure not related, reiterated, to some "original".

 

[fineMen]

... a matter of taste, not quality. And for sure not related, reiterated, to some "original".

Question is, how to exploit the standard the most. I still advertise to individually equalise the stereo setup @home to the standard for starters. A not too bad scoring speaker would allow for that. The spinorama helps informed consumers to select feasible choices.

In case of special demand, e/g if someone is into the 'phillysound', a different, more suitable e/q might help. Specialised dealers could, and I think they should, support their valuable customers with this. Such collaboration would bring a new service to the market and stabilise the stance of the dealer.

 

[Floyd Toole]

@Floyd Toole thank you for joining. In your book there is figure 7.16 where spatial ratings was found to be highly program related. I doubt that found preferences hadn't reflected to sound quality preferences, but I couldn't find such results. Do you have any?
View attachment 192981

Also in Room effects test is said that loudspeakers with similar directivities and similary good performance were used. Of course that different rooms hadn't make much difference - loudspeakers were similar. But IMO it is quite possible that if loudspeakers with different qualities (not similar) were used the results would be different.

I wish I had good news for you, but the original data file for these experiments disappeared in the move to California. There were several filing cabinets of data that had to be sorted through and either discarded or saved. Mistakes were made. I too would like to have another look at the original data. It is interesting that in almost 40 years nobody else has bothered to repeat or extend this kind of work and publish the results.

As for the choice of loudspeakers for the multiple-room tests, if you look at the authors of the paper my name is not among them. I had the facility for the experiment constructed while I was at the NRC directing the research, but the experiments were designed and run after I left to join Harman International. I agree with the choice of loudspeakers, though, because it was a difficult discrimination test and it truly showed the remarkable room adaptation that humans are capable of. The experiment, as you can imagine, was arduous and time consuming ($$$$), so it is understandable that it was not repeated using loudspeakers that would have been easier to recognize, such as those having distinctive directivities. In that respect, I have to say that at that time it would have been difficult to find examples having distinctive directivity that were similarly neutral - thereby allowing directivity to be the dominant variable. Most directionally distinctive loudspeakers of the time also were distinctive in their sound signatures, making them easily recognizable and invalidating the experiment. It could be done better these days, but finding someone with the competence and facilities to do it is a real challenge!

Personally, now that we have truly excellent "conventional" loudspeakers, and the option of supplemental surround/multichannel loudspeakers and processors I do think we have moved on. These days there is little or nothing to be gained in distinctive transduction processes beyond marketing claims. Loudspeakers with bipole, dipole, and omnidirectional behavior are not involved with the creation of the art in the professional audio domain, so their involvement in playback is that of adding a "sound effect" that people find pleasurable - it all comes down to attempts to extract more satisfaction from stereo. Whether it is real or imaginary is unimportant. I had monster bipole loudspeakers in one of my systems, as discussed and shown in my book. It was done deliberately for a special listening room (Figure 7.19). They would not be optimum for my existing listening circumstances (Figure 7.21) - references to Figures in the 3rd edition of my book.