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Maybe it's old data or wrong to begin with, but some years ago I read that our hearing mechanism is comprised of a bunch of ~ 1/6th (I think) octave oscillators, and that what we hear in any one of those bands is the total energy in its passband, ergo high-Q resonances are not very audible.

Is that incorrect?
There is a school of thought, and research, that would say this is incorrect.

Matter of Fact, that school may say that high peaks are ALL you hear.


from http://drc-fir.sourceforge.net/doc/drc.html#htoc32

The spectral envelope is a concept which has been introduced in the field of speech synthesis and analysis and is defined simply as a smooth curve connecting or somewhat following the peaks of the signal spectrum. There are strong arguments and experimental evidence supporting this approach and the idea that our ear uses the spectral envelope for the recognition of sounds. The spectral envelope, for example, allow our ear to understand speech under many different conditions, whether it is voiced, whispered or generated by other means. These different conditions generate completely different spectrums but usually pretty similar spectral envelopes. The spectral envelope also easily explains why our ear is more sensitive to peak in the magnitude response and less sensitive to dips. A curve based on the peaks of the magnitude response is by definition little or not affected at all by dips in the frequency response.

In the speech recognition field many procedures have been developed to compute the spectral envelope. Some of them are based on Linear Predictive Coding (LPC), the Discrete Cepstrum, the so called “True Envelope” and finally the Minimum Variance Distortionless Response (MVDR). Most of these methods are optimized for speed, noise resilience and to provide good results in the voice spectrum range sampled at low sample rates, so they are not really suited for HiFi usage.

Within DRC a different procedure has been developed. This is a variation of the usual fractional octave smoothing procedure, using the parametric Hölder mean instead of the usual simple averaging. Furthermore the smoothing has been extended to provide the Bark and ERB scales resolution when applicable.
 

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I would like to ask the organizer to ,if possible, include objective measurements like harmonic distortion at the same volume level, intermodulation distortion etc

BTW, I bet

m2 wins in the lows, S2 wins the highs
M2 wins at high volume , S2 wins at low volume
M2 wins for movies, and S2 wins for music
M2 wins dynamics, S2 wins soundstage

at the end of the day a tie, tipping towards the M2 as waveguides are all the rage right now, and of course the M2 is Master Reference
 
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I would like to ask the organizer to ,if possible, include objective measurements like harmonic distortion at the same volume level, intermodulation distortion etc

BTW, I bet

m2 wins in the lows, S2 wins the highs
M2 wins at high volume , S2 wins at low volume
M2 wins for movies, and S2 wins for music
M2 wins dynamics, S2 wins soundstage

at the end of the day a tie, tipping towards the M2 as waveguides are all the rage right now, and of course the M2 is Master Reference
Agree with all but that one. The soundstage on properly setup M2's is simply massive and amazing. :) If S2 better it would be quite the experience.

I'll go with: M2 wins dynamics and soundstage
 

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There is a school of thought, and research, that would say this is incorrect.

Matter of Fact, that school may say that high peaks are ALL you hear.


from http://drc-fir.sourceforge.net/doc/drc.html#htoc32
This is always a challenge. All perceptual models, however elaborate, attempt to replicate what humans can hear - they do not define what humans can hear. I played with primitive neurological models in my PhD sound localization work in the early '60s.

The simple fact is that humans can hear, and identify the sound of very high Q resonances. In the 1988 paper I referred to earlier, and in my books, it is clear that Q=50 resonances are recognizable and audible, but the thresholds of audibility are higher than for lower Q resonances - as measured in the frequency response. Part of the reason why the thresholds are high is that they occupy a small spectral footprint, meaning that a sound of a quite specific frequency must be present long enough to energize the resonances. It is basic physics. Such sounds are relatively rare in music, compared to lower Q resonances that can be energized by a wider range of frequencies. So, logically, the detectability of resonances is very dependent on the program material. Close miked rock and roll is very forgiving. As the spectral density increases and reverberation is included, thresholds drop. Reflections make us more sensitive to resonances - they are repetitions, giving the listener repeated "looks" at the sound.

The concept that critical bands, ERBn and such are measures of the resolution of the hearing system are faulty. They have meaning, but this is not it. This is discussed in my original book, and more elaborately in the new one.
 

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In the 1988 paper I referred to earlier, and in my books, it is clear that Q=50 resonances are recognizable and audible, but the thresholds of audibility are higher than for lower Q resonances - as measured in the frequency response. Part of the reason why the thresholds are high is that they occupy a small spectral footprint, meaning that a sound of a quite specific frequency must be present long enough to energize the resonances. It is basic physics. Such sounds are relatively rare in music, compared to lower Q resonances that can be energized by a wider range of frequencies. So, logically, the detectability of resonances is very dependent on the program material. Close miked rock and roll is very forgiving. As the spectral density increases and reverberation is included, thresholds drop. Reflections make us more sensitive to resonances - they are repetitions, giving the listener repeated "looks" at the sound.
Does this have implications for the choice of programming at the shootout?
 

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Does this have implications for the choice of programming at the shootout?
Yes. There is music for "selling" and music for "shopping". Audiophile "demo" music is often simple closeup vocals or solo instruments which can be dramatic to listen to but is spectrally simple and frankly it can sound good through flawed loudspeakers. As the band gets more members, some reverb is added, and genuine bass and treble get into the mix, the challenge for loudspeakers is much increased. Voice, by itself is not very revealing of common problems.

John and Sean Olive are in touch about some up-to-date material that has passed the test.

Pink noise will reveal tiny differences, even though we are never quite sure what it should sound like. If there is a significant resonance it will be revealed, although it may or may not be audible in music or movies.
 

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This is always a challenge. All perceptual models, however elaborate, attempt to replicate what humans can hear - they do not define what humans can hear. I played with primitive neurological models in my PhD sound localization work in the early '60s.

The simple fact is that humans can hear, and identify the sound of very high Q resonances. In the 1988 paper I referred to earlier, and in my books, it is clear that Q=50 resonances are recognizable and audible, but the thresholds of audibility are higher than for lower Q resonances - as measured in the frequency response. Part of the reason why the thresholds are high is that they occupy a small spectral footprint, meaning that a sound of a quite specific frequency must be present long enough to energize the resonances. It is basic physics. Such sounds are relatively rare in music, compared to lower Q resonances that can be energized by a wider range of frequencies. So, logically, the detectability of resonances is very dependent on the program material. Close miked rock and roll is very forgiving. As the spectral density increases and reverberation is included, thresholds drop. Reflections make us more sensitive to resonances - they are repetitions, giving the listener repeated "looks" at the sound.
Thanks for making a point I've been meaning to make ... that the reason that lower Q resonances are more audible is simply that they are more readily energized by real content. The worst case, of course, would be music consisting of long-running pure tone sine waves. In that situation, we really can "hear" the frequency response as it would be measured at each ear.

The concept that critical bands, ERBn and such are measures of the resolution of the hearing system are faulty. They have meaning, but this is not it. This is discussed in my original book, and more elaborately in the new one.
I look forward to reading your criticism of this concept. Though, I believe critical band theory actually is very useful. The point to realize is that just because the bands / ERBs may be only 1/3rd to 1/9th octave wide doesn't mean that we can't hear frequencies at higher resolution than that. So long as the sampling time interval of the hypothetical cochlear filter system is short enough, the brain has sufficient to information to assess frequency much more precisely than the bandwidth of the filters themselves.

I suspect that we can take away at least one useful piece of information from the critical band experiments. We may be able to conclude a rough upper bound on the temporal resolution of the hearing system. I believe the actual resolution is frequency dependent and may be approximately represented as a Gaussian time window whose Fourier transform is also a Gaussian with a 1/3rd octave bandwidth. This information can be used, in turn, to estimate the ability of the hearing system to independently resolve direct sound arrivals and reflections at different frequencies.

My own experiments, albeit based entirely on my own non-blind subjective judgment, suggest that 1/3rd octave is the optimal bandwidth to use for assessing the overall spectral balance of sound. Therefore, this is the resolution to use with frequency dependent windows (aka complex smoothing and not magnitude smoothing) when fitting in-room response to a desired target. Much higher resolutions do, of course, remain useful for assessing resonances, but 1/3rd octave is king for overall tonal balance.

My experiments suggest that the desired target for music is flat for most of the mids and highs, has a slight dip (maybe 1 dB or so) in the low mids/upper bass (very roughly 175-350 Hz), and slopes up several dB as frequency drops into the sub bass range. Presumably this target approximately reflects what happens to the first arrival sound from a "typical" speaker that measures flat under anechoic conditions and is placed near a floor but far away enough from the other boundaries that their reflections are easily distinguished by the hearing system until much lower frequencies (likely well into the modal region, in many cases). Interference with the floor creates the dip and subsequent rise in the sub bass range in the first arrival sound.

I can't recall where I found it, but I believe Harman has published a headphone target curve, which was determined using listener experiments. IIRC, its low frequency characteristics look very similar to the curve I describe above, including the slight upper bass / low mid dip.

Of course in reality, the region of the dip and rising bass response for an anechoic speaker placed in-room will vary substantially depending on the listener distance, the distance between the woofer(s) and floor, and crossover characteristics. However, mix and master engineers strive to achieve consistency in their work by comparing their work to existing content. In this way, the Circle of Confusion works to our advantage by reducing variation in tonal balance that might otherwise arise, even when using perfectly flat monitors, due to differences in driver orientation, room placement, and listener distance that impact sound below 500 Hz.
 

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Agree with all but that one. The soundstage on properly setup M2's is simply massive and amazing. :) If S2 better it would be quite the experience.

I'll go with: M2 wins dynamics and soundstage

upperbass and midrange sensitivity is on the order of 10db higher in the M2 (power handling is higher as well), so a proper characterization of this "shootout" would be akin to a modest load .22 going head to head with a hot loaded .44 magnum. if the .22 will get your job done, fine, but without taking each to the limit, significant performances differences may remain veiled.


how will soundstage be tested in a blinded mono comparison?
 

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Yes. There is music for "selling" and music for "shopping". Audiophile "demo" music is often simple closeup vocals or solo instruments which can be dramatic to listen to but is spectrally simple and frankly it can sound good through flawed loudspeakers. As the band gets more members, some reverb is added, and genuine bass and treble get into the mix, the challenge for loudspeakers is much increased. Voice, by itself is not very revealing of common problems.

John and Sean Olive are in touch about some up-to-date material that has passed the test.

Pink noise will reveal tiny differences, even though we are never quite sure what it should sound like. If there is a significant resonance it will be revealed, although it may or may not be audible in music or movies.
These are interesting points. Another thing I've noticed is that more compressed / loud music is often more differentiating of linear response characteristics, especially when it contains many different parts. I think the lack of dynamics suppresses the attacks that otherwise make it easier to distinguish the different parts.

While it's frustrating that so much music is mastered to be loud instead of more dynamically natural, I do find that more accurate reproduction makes listening to this kind of music more enjoyable, even though it's easier to hear artifacts like pumping.
 

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upperbass and midrange sensitivity is on the order of 10db higher in the M2 (power handling is higher as well), so a proper characterization of this "shootout" would be akin to a modest load .22 going head to head with a hot loaded .44 magnum. if the .22 will get your job done, fine, but without taking each to the limit, significant performances differences may remain veiled.


how will soundstage be tested in a blinded mono comparison?
Good question. Aspects of soundstage that depend on stereo reproduction obviously won't be tested. But I believe some aspects of soundstage are actually based on mono cues. In my experience, response of the last octave or so (especially above 15 kHz or so), both within that span and relative to the rest of the response, has a lot of influence on perceptions of depth of space.

Measurements suggest that the M2 and Salon 2 have some substantial differences at the highest frequencies. The directivity of the M2 narrows a lot faster than the Salon 2, but it appears to offer more overall output. Response on-axis actually ramps up toward the top. Opinions of the M2 in this respect may be more sharply divided depending on listener location with listeners on-axis getting a lot more upper frequency content than listeners off-axis. When I listened to the M2s in in John's room, I believe I was able to hear the beaming by moving my head from side-to-side. I'll probably want to avoid doing that during the blind tests because any hint as to which speaker I'm listening could spoil the rest of my assessment.
 

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Agree with all but that one. The soundstage on properly setup M2's is simply massive and amazing.
If S2 better it would be quite the experience.

I'll go with: M2 wins dynamics and soundstage

upperbass and midrange sensitivity is on the order of 10db higher in the M2 (power handling is higher as well), so a proper characterization of this "shootout" would be akin to a modest load .22 going head to head with a hot loaded .44 magnum. if the .22 will get your job done, fine, but without taking each to the limit, significant performances differences may remain veiled.


how will soundstage be tested in a blinded mono comparison?
Exactly!!!!!!!!!!
 

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upperbass and midrange sensitivity is on the order of 10db higher in the M2 (power handling is higher as well), so a proper characterization of this "shootout" would be akin to a modest load .22 going head to head with a hot loaded .44 magnum. if the .22 will get your job done, fine, but without taking each to the limit, significant performances differences may remain veiled.


how will soundstage be tested in a blinded mono comparison?
I guess you have to experience it to believe it. I did my first stereo vs mono test in 1985 and it was a very thorough and carefully conducted blind test. All of this is in JAES papers and in both books, so I won't get into regurgitating old research. The amazing reality is that listeners reported extensively on spatial/soundstage characteristics when listening in mono - which everyone, myself included, thought would be commented on only in stereo. The spatial ratings in mono closely tracked the sound quality ratings, and both were more strongly differentiated in mono than in stereo listening. We have learned since then that sound quality and spatial quality are closely linked.

In mono, the highest rated loudspeakers came closest to "disappearing" behind the screen, leaving impressions of image size and distance/depth to information in the recordings. Because stereo is mono L, mono R and double-mono amplitude and/or delay panned phantom images (including of course the featured artist), it is understandable that the soundstage is improved if one's attention is not drawn to the loudspeakers. This tends to be an advantage for wide dispersion loudspeakers. It was interesting to see that the mono ratings agreed with stereo ratings for close miked, pan potted stereo pop (truly multiple mono). With more complex pop and classical music there is a huge amount of uncorrelated information in both channels (to generate the desired spaciousness) and the spatial/soundstage ratings were not strongly differentiated. The dominant factor in the stereo tests was the recording itself, which, if you know how the signals are captured and processed, is not surprising. These are control room creations.

Over the years we have done a few stereo vs. mono tests to convince skeptics with the same result: the highest rated loudspeakers in mono, have been the highest rated loudspeakers in stereo but the differentiation in stereo was not always as easily discerned. Highly directional loudspeakers tend to stand out as lacking in both stereo and mono. Recently, the comparison has been expanded to multichannel, and it is even more forgiving than stereo. The more channels that are simultaneously active, the less the room interactions can be heard. But we listen in mono much of the time, in multi-mono stereo in non-classical music, a dominant center channel in movies and any time a signal is hard panned to a single channel. So how a loudspeaker sounds in mono matters, and mono tests yield the most critical comments. In stereo expect a speaker to be no worse, possibly better, but the stereo soundstage is definitely engaging :)
 

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Don't forget, everyone, we will follow up the blind mono listening tests with stereo listening sessions of each speaker. The caveat is that these will not be blinded.

Idea being that it will be fun to just listen to stereo music with both excellent speakers once we go through the trials. A way of unwinding after the critical listening, if you will :)
 

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This sounds like a great shootout of great speakers. Its nice to see some good words being said about measurements, Harman and Dr.Toole since most other audio manufactures refuse to provide any specs or measurements and operate solely on marketing.

I wish the Infiniti P363 was still being made and sold, I remember reading many good things about it on Sean Olive's blog and how it was the hidden gem of their lineup, at a price point of $100-150 each :eek:
 

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All this talk, movies vs. music. As a sometime film composer, I must object. There is no "movies vs. music." Most films have LOTS of music in them.

It's the most important part of the soundtrack :)
+1

Great cinematic scores are as responsible for telling the story as the director, actors, cinematographer, etc. The Lord of the Rings is a prime example.
 

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All this talk, movies vs. music. As a sometime film composer, I must object. There is no "movies vs. music." Most films have LOTS of music in them.

It's the most important part of the soundtrack :)
That sounds good and all but i find it kinda simplistic.

Film music has more dynamic range , thus the dynamics of a speaker play in.
Film music would be mixed or equalized on a system that has x-curved baked in. I dont know of any music studio that uses x curve for non film music
 

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This is always a challenge. All perceptual models, however elaborate, attempt to replicate what humans can hear - they do not define what humans can hear. I played with primitive neurological models in my PhD sound localization work in the early '60s.

The simple fact is that humans can hear, and identify the sound of very high Q resonances. In the 1988 paper I referred to earlier, and in my books, it is clear that Q=50 resonances are recognizable and audible, but the thresholds of audibility are higher than for lower Q resonances - as measured in the frequency response. Part of the reason why the thresholds are high is that they occupy a small spectral footprint, meaning that a sound of a quite specific frequency must be present long enough to energize the resonances. It is basic physics. Such sounds are relatively rare in music, compared to lower Q resonances that can be energized by a wider range of frequencies. So, logically, the detectability of resonances is very dependent on the program material. Close miked rock and roll is very forgiving. As the spectral density increases and reverberation is included, thresholds drop. Reflections make us more sensitive to resonances - they are repetitions, giving the listener repeated "looks" at the sound.

The concept that critical bands, ERBn and such are measures of the resolution of the hearing system are faulty. They have meaning, but this is not it. This is discussed in my original book, and more elaborately in the new one.
Hi Sir,

I think my post was essentially agreeing with yours that we need smaller fractional averaging . 1/6 from my experience will miss many peaks that are very audible
 
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That sounds good and all but i find it kinda simplistic.

Film music has more dynamic range , thus the dynamics of a speaker play in.
Film music would be mixed or equalized on a system that has x-curved baked in. I dont know of any music studio that uses x curve for non film music
Hah! I thought you were going to write something like: "No it's not. The dialog is the most important part of the soundtrack."

To your points, film scores do not necessarily have more dynamic range than music. It does on average only because so many music mixes are made so loud.

In fact, mixes for cinema probably don't have nearly as much dynamic range as you'd think. Both the pink noise calibration method and X curve target contribute to a substantial reduction in effective dynamic range versus home presentations. I estimate that on a per-channel basis, after accounting for these effects, a cinema mix has about the same dynamic range as a K-14 music mix. The cinema does have a center channel, plus a couple of surrounds (albeit at -3 dB), but it must also share the space with dialog, sound effects, and ambiance tracks.

The X curve target does adversely effect the sound quality of movie soundtracks, when played in the home especially, but in the cinema too. Fortunately "home" mixes are becoming more common, and their quality seems to be improving. More of these mixes are being done in dedicated spaces and using higher quality monitors like the JBL M2s or 708s. Better monitors are more revealing of tonal balance problems, allowing mixers to correct these issues, leading to a superior audio experience in the home than is currently possible in cinemas.
 
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