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Which speakers are the Classical Music Pros using?

youngho

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This is definitely true for me. Rating purely the "Spacial" component, I rate wider dispersion higher in mono, and medium or narrow dispersion higher in stereo.

For mono listening, I prefer the spatial presentation of my Revels far more than I do my JTRs(narrow dispersion) or Genelecs(medium dispersion). The Revel throws a wider soundstage and disappears much better, which are the 2 components of how I rate "spatial" quality from 1-10.

In stereo, I actually rate the Revel the worst of the 3. The Revel still disappears a bit better, and it still throws a wider soundstage, but, it now does worse on the (new) third component, which is the tightness of the phantom center image. This may just be a personal preference, but I love tighter phantom imaging more than I love wider soundstage, excluding some types of symphonic music. For certain types of symphonic music, I actually enjoy a more diffuse phantom image, as it sounds closer to what I hear at live symphonic events.
I used Tapio Lokki's 2019 and 2016 paper on listening room, concert hall acoustics, and listener preferences to idly speculate on a model of listener preference and loudspeaker characteristics: proximity/clarity (high directivity conventional loudspeaker and/or absorption of early reflections), width/envelopment (wide directivity conventional loudspeakers and/or preservation of lateral reflections), reverberance/spaciousness (omnidirectional, possibly bipolar speakers splitting the difference between this and clarity/proximity), timbre (many critical listeners of classical music seem to like wider baffle speakers, and my speculation is that relatively constant, rather than smoothly rising, directivity between several hundred and several thousand hertz may contribute to this), and bass. These characteristics aren't necessarily mutually exclusive--for example, Earl Geddes called for extremely high directivity speakers to be used but with strong later contralateral reflections--but listeners might weight the individual characteristics in terms of relative importance in consider loudspeakers and listening room setups.

In your case, I correlate proximity/clarity with preference for "tight" or "pinpoint" imaging. I even wonder whether this preference may correlate with narrow baffle or smoothly rising directivity, but I have no evidence to support that.

A year or two ago I blinded the Genelec 8030c against the Revel M105, but only in stereo. I really wish I had done a subsequent mono test to see if the results changed. The Genelec won the stereo test, but I'm pretty confident the Revel would win a mono test. The reason I think this is twofold:

1. Tonality is almost identical, so it's gonna come down to the "Spatial" rating
2. The Genelec slightly won(imo this is why it won) because of the spatial component, which was due to the tighter phantom image it throws. I'm somewhat guessing this is why it won based on why I prefer it, and comments from the listeners. A common comment in favor of the Genelec was something like "this one sounds more like the singer is there in front of you". In mono, though, I actually rate the Revel higher for its spatial representation. There is no phantom image anymore, and the narrower dispersion makes it clearer that the sound is coming from a speaker right in front of you, which means the Genelec doesn't "disappear" as well as the Revel.
I might idly speculate that the wider directivity enhances the perception of width/envelopment, resulting in less pinpoint localization of "the speaker is exactly right there."
One thing that may be the cause of some difference is: "What question are you trying to answer with this blind test?". Are you trying to find which speaker sounds best with "average" placement/toe-in? Or, are you trying to find which speaker sounds best with "optimal" placement/toe-in? I think the Harman research was aimed more at answering the former, whereas my tests were aimed more at answering the latter.

For answering the first question, the way Harman does it(speakers in same spot with same toe-in) makes the most sense, as user room placement and toe in will likely be all over the place. Doing it like this does definitely bias the results towards wider dispersion, and Dr. Toole has even mentioned this too. But, Dr. Toole also brings up the great point that this bias is not really a bad thing, as placement insensitivity is an inherent advantage of wide dispersion. My Revels sound great without much setup at allb at almost any position. Sure, you can optimize it a bit(maybe 10%?) by messing with toe-in, but they pretty much always sound great. My JTRs on the other hand are much more finicky. They go from sounding bad to sounding amazing just by adjusting the toe-in a bit.

For answering the second question, you would need to first find the optimal position and toe-in for each speaker under test, and then design a machine that can quickly place each speaker in that optimal position and orientation. Such a machine would likely be much more expensive and complicated, and maybe isn't answering the question that is most important to a manufacturer. The way we handled this was by spending a few days prior to the event finding the optimal placement/toe-in for each speaker, and then marking those positions with color coded tape for each speaker. On test day, when the listener called for the switch, we had two people to move the current speakers out of the way, and two people to move the new speakers into the color coded position/angle. It seemed to work really well, but requires a good number of people, and also our switch times weren't 3 seconds or less like the Harman switcher is(I'm hoping the ABX comparator can assist with this).

Anyways, glad to see Dr. Toole participating here, and this is something I'm super curious to see more research about. A loudspeaker like the Beolab90 would perhaps be an excellent test subject. Maybe the "wide" or "omni" mode is preferred in mono? Maybe the "narrow" mode is preferred in stereo? To truly answer this mono vs stereo debate for myself, I need the ability to hold the FR component as a constant, and let dispersion width be the only variable.
The Beolab 90 would first have to be shown to be virtually identical between directivity modes. I personally believe that the best current way to begin to address the questions in the way that you're outlining would be with simulated listening environments (and simulated loudspeaker directivity indices of varying curves) using a setup like the Aalborg array outlined here.
 

richard12511

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Perhaps wide-directivity is the best choice for pop music?

I actually find the opposite to be true, though I assume this is a matter of preference.

For pop/rock, or anything that has a singer as the main center phantom image(which is maybe 60% of what I listen to), I prefer more medium or narrow directivity. I think I like it because the tighter center singer image sounds more like real life(to my ears). This is also why I prefer coaxials here. Wider dispersion speakers widen/heighten the center image, which tends to make the vocal unnaturally wide/tall. Real human voice 3m in front of you in room has a very small/tight "image".

For 2 channel(Auro3D upmixing gives the best of both worlds :)) symphonic music, I think I prefer wider dispersion. I think it's for the same reason, that is the bigger and more diffuse center image sounds more like what I hear at a real symphony hall. I think it has to do with the ratio of direct to indirect sound. If you're near the back of a hall, you're hearing a very high percentage of indirect sound, and wider dispersion speakers probably get closer to recreating that, at least for some symphonic recordings. Other recordings sometimes have enough indirect sound in the recording already, and those might work better with narrower dispersion.

More and more, I'm moving towards having multiple systems with different directivity to satisfy the content and/or my mood.
 
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Descartes

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Here is an other interesting recording studio using 5 KEF BLADE 2

 

Blumlein 88

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Nice example of a simple unprocessed two microphone recording. Using a pair of ribbons in a Faulkner array. You can give it a listen streaming in the post.
 

Duke

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Any amount of front soundstage sound that directly makes its way into the upmixed surround channels cannot be good, even with a modest delay.

Does the derivation of a difference signal for the surround channels effectively keep the front soundstage sound out of them?

Another question arises from my upmixing ignorance: Are the settings on your processor "set and forget", or do the ideal settings vary from one recording to the next? (The "ideal setting" variation from one recording to the next is what ultimately led me to give up on the "Hafler hook-up" many decades ago. Sometimes I wouldn't find a seemingly "correct" level setting for the difference signal until the song was practically over, and sometimes I never did.)

... envelopment - what we are most interested in for upmixing, mainly involves middle frequencies. Add to this that to be perceptually effective the delays need to be substantially greater than can be generated naturally in small rooms.

I absolutely agree that the sort of in-room reflection arrival times we get in a two-channel home audio setting are inadequate for generating envelopment. But there is arguably another potential source of envelopment cues, namely the ambience cues on the recording, which (given a good recording) would include reverberation tails arriving after a realistic time delay. So theoretically we have two competing sets of spatial cues: The "small room signature" cues inherent to the playback room; and the venue cues on the recording, whether said venue cues be real or engineered or both. Is this "two competing sets of venue cues" paradigm a realistic and reasonable one?

My memory of the original (RIP) Lexicon Logic 7 upmixer is that it did an excellent job of separating the soundstage from the surround sound....

I share your sentiments.

Kevin Voecks comments here, combined the off-axis measurements shown here (particularly above ~7 kHz, note crossover frequency for rear tweeter was 8 kHz), lead me to conclude that your overall interpretation for the original intention was correct ("uniform power response"), but then read here to see his explanation for the elimination, which differs from your subsequent speculation.

Youngho, your replies consistently pack an enormous amount of information into a minimal number of words. Thank you for those links. I had forgotten about that interview, wherein Kevin clearly explains that the tweeter waveguide on the Salon 2 not only fixed the power response, but corrected the spectral balance of the first sidewall reflections. Brilliant.
 
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Newman

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I absolutely agree that the sort of in-room reflection arrival times we get in a two-channel home audio setting are inadequate for generating envelopment.
Also the direction is wrong, otherwise we could achieve it with a delay loop.
 

Duke

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Also the direction is wrong, otherwise we could achieve it with a delay loop.

I assume you're referring to reflections which arrive from the same direction as the first-arrival sound; my understanding is that that's arguably the worst possible direction for reflections to come from.

But assuming the playback room isn't overdamped, we should be getting reflections from many directions.
 

Floyd Toole

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If you look at Section 15.7.1 in the 3rd edition and 15.10.2 in earlier editions you will see that in terms of creating enveilopment "classic" 5.1 is an excellent substitute for a much higher number of channels. You will also see that having a center channel is an advantage, so adding two surrounds to stereo is not the best solution. The brain likes to have a "real" frontal sound to start the perceptual countdown and analysis. The optimum direction for the side reflections may be closer to 60 deg, which is where real wall reflections come from in many performance venues - see Figure 7.5 and related text in the 1st/2nd editions. You will also see that two channel and classic quadraphonics were much inferior. It is definitely time to change.
 

youngho

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Youngho, your replies consistently pack an enormous amount of information into a minimal number of words. Thank you for those links. I had forgotten about that interview, wherein Kevin clearly explains that the tweeter waveguide on the Salon 2 not only fixed the power response, but corrected the spectral balance of the first sidewall reflections. Brilliant.
@Duke I am dense. Also with allusion and/or explicit reference. Classic amateur who's read a little but speculates much, that's me. If I don't write a little, I write a lot.
Also the direction is wrong, otherwise we could achieve it with a delay loop.
@Newman Newman! Since you're still actively participating, I am looking forward to your layman's (for my benefit) explanation of some degree of specificity regarding the differential in what you call "neurological components" (or what I call brain activity) between live and recorded music experience, beyond what I've already outlined above. Thank you.
 

Newman

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I would be curious to see what references you can provide to support these specific statements, outside of the visual and possibly tactile aspects of the live music experience being absent from non-video music recordings.
I did actually attempt to find any old references I may have saved that could help you, but no luck. It was many years ago. I did stumble upon a couple of old posts I would have posted on other forums at the time when I must have seen the research material, but they basically say the same thing, and also don't provide references.
 

Newman

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having a center channel is an advantage, so adding two surrounds to stereo is not the best solution. The brain likes to have a "real" frontal sound to start the perceptual countdown and analysis.
This is great for multichannel source material, but my experience with upmixed stereo (I haven't yet tried Auro-3D) is that a centre channel makes the centre image collapse to something much smaller than in stereo, and not in a very satisfying way. I suppose better up mixers don't do that... but it is almost as if the stereo mixing is done in the knowledge that they could make the centre panned material bigger than just the width of a centre speaker...but then the up mixer signs it all to just the centre speaker and it diminishes.

I have had to adjust the upmixing to spread some of the centre front 'assignment' back to FL and FR. That helps.

(These are just impressions from me and a few visitors over time.)
 

pozz

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If I may offer a critical reply from a purist. In the earlier part of your post you've thrown the baby right out with the bathwater. We abandon the goal of life-like reproduction? Haven't you experienced the benefit of pursuing a goal knowing it is always somehow unobtainable and yet the pursuit can give us fantastic results if we don't give up? Always getting closer, but never able to fully arrive there.

Now I'll not argue that excellent results aren't possible using the close mic, multi mic approach. Nor that with large groups especially it is easier to get good results. Without a definite goal however some results are better than others and not everyone is shooting for the same result, but rather a plausible nice result with no one able to definitively say what is nice and what is not.
I think the real goal, where life-like reproduction is a just a stop along the road, is arbitrary control of all auditory perceptions. Size, width, position, distance, ambience. In that sense I would agree with @Newman. Until we have this ability we won't have the other.
 

Blumlein 88

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I think the real goal, where life-like reproduction is a just a stop along the road, is arbitrary control of all auditory perceptions. Size, width, position, distance, ambience. In that sense I would agree with @Newman. Until we have this ability we won't have the other.
Object oriented formats already claim to be able to do this. I've not heard any so don't know how much is Ad copy and how much is true.
 

pozz

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Object oriented formats already claim to be able to do this. I've not heard any so don't know how much is Ad copy and how much is true.
There are limitations with sweet spot, colouration, image clarity and stability. Definitely well along the path though. I've never heard the current pinnacle either, which are WFS or full ambisonic systems. Or JJ's system. I'm not sure what the principles are used for the latter, and I would visit it and a few others in research institutes if not for international travel restrictions.

One of the issues, beyond all the complexity of technique, is that some of the cues we use to localize accurately are not auditory (not just visual, but also familiarity with a space, mental mapping). Unclear how to get around that.

Come to that, I don't know that I've heard the pinnacle of stereo either, but I'm sure I've come close. Some systems are really freakin great.
 

richard12511

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This is great for multichannel source material, but my experience with upmixed stereo (I haven't yet tried Auro-3D) is that a centre channel makes the centre image collapse to something much smaller than in stereo, and not in a very satisfying way. I suppose better up mixers don't do that... but it is almost as if the stereo mixing is done in the knowledge that they could make the centre panned material bigger than just the width of a centre speaker...but then the up mixer signs it all to just the centre speaker and it diminishes.

I have had to adjust the upmixing to spread some of the centre front 'assignment' back to FL and FR. That helps.

(These are just impressions from me and a few visitors over time.)

Dolby upmixer definitely does what you describe, and I also hate it. You can mostly fix it by turning "Center Spread" on for the Dolby configuration, but not all AVRs allow that. Auro3D doesn't do that. At the strength I use(6-7) it more or less just heightens and widens the soundstage, and makes the center image a bit more stable.
 
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Blumlein 88

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There are limitations with sweet spot, colouration, image clarity and stability. Definitely well along the path though. I've never heard the current pinnacle either, which are WFS or full ambisonic systems. Or JJ's system. I'm not sure what the principles are used for the latter, and I would visit it and a few others in research institutes if not for international travel restrictions.

One of the issues, beyond all the complexity of technique, is that some of the cues we use to localize accurately are not auditory (not just visual, but also familiarity with a space, mental mapping). Unclear how to get around that.

Come to that, I don't know that I've heard the pinnacle of stereo either, but I'm sure I've come close. Some systems are really freakin great.
JJ's system is surprisingly simple. What little has been said of it was high praise for how real it could sound. Playback is to assigned channels and recording microphones are specified as well. It was a 7.1 system using 9 recording microphones in a pattern slightly larger than someone's head. Two mics were for encoding up and down into the other channels thru a simple calculation that worked as it should. Or today i suppose you could add those two height channels in a 9.1 system. In which case no calculations or signal mixing would be needed, it would track straight channel to channel the way stereo does.
 

pozz

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JJ's system is surprisingly simple. What little has been said of it was high praise for how real it could sound. Playback is to assigned channels and recording microphones are specified as well. It was a 7.1 system using 9 recording microphones in a pattern slightly larger than someone's head. Two mics were for encoding up and down into the other channels thru a simple calculation that worked as it should. Or today i suppose you could add those two height channels in a 9.1 system. In which case no calculations or signal mixing would be needed, it would track straight channel to channel the way stereo does.
I would love to hear it. But what I would really love, beyond that, is to stop relying on microphones and recordings for the most intense realism. My favorite music is all electronic/digital. There is some seriously amazing synthesized stuff out there, but nothing that captures the complexity of acoustic spaces in great recordings. Some producers mess with convolving room responses with their music, but IMO the results are underwhelming and muddy compared to simpler techniques. Or maybe we just aren't doing the right things. In any case for this kind of music we are stumbling around looking for the best way forward.
 

pozz

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Dolby upmixer definitely does what you describe, and I also hate it. You can mostly fix it by turning "Center Spread" off on the Dolby configuration, but not all AVRs allow that. Auro3D doesn't do that. At the strength I use(6-7) it more or less just heightens and widens the soundstage, and makes the center image a bit more stable.
Have you ever tried upmixing and then monoing the center (or other channels individually)? Can you hear artefacts?
 

Duke

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If you look at Section 15.7.1 in the 3rd edition and 15.10.2 in earlier editions you will see that in terms of creating enveilopment "classic" 5.1 is an excellent substitute for a much higher number of channels... It is definitely time to change.

I just read that chapter recently. Hugh Brittain's cross-firing configuration has this advantage in addition to image stabilization: It results in significant contralateral reflections which presumably contribute to reduced interaural cross-correlation and therefore improved sense of envelopment. That being said, my persistence in trying to mine two-channel playback for "envelopment" might be like "trying to find gold in a silver mine" (apologies to Elton John and Bernie Taupin).

The optimum direction for the side reflections may be closer to 60 deg, which is where real wall reflections come from in many performance venues - see Figure 7.5 and related text in the 1st/2nd editions.

After reading that section in the first edition of your book, my next design was a "twisted bipolar"which illuminated the 60 degree reflection area quite well. However I now think it put too much energy into those first sidewall reflections, unless the speakers were located along the "long wall" of a fairly wide room. If I had incorporated level controls and delay like Ken Kantor did in the MGC-1, it might have turned out differently.

This is great for multichannel source material, but my experience with upmixed stereo (I haven't yet tried Auro-3D) is that a centre channel makes the centre image collapse to something much smaller than in stereo, and not in a very satisfying way. I suppose better up mixers don't do that... but it is almost as if the stereo mixing is done in the knowledge that they could make the centre panned material bigger than just the width of a centre speaker...but then the up mixer signs it all to just the centre speaker and it diminishes.

I spent some time with a trinaural processor yeas ago and to my ears the soundstage depth in the middle collapsed to the center speaker, which became the obvious sound source (easily localizable behind a screen). Normal stereo, on the other hand, had good depth in the center of the soundstage, and the left and right speakers were not obvious sound sources. Presumably there was a timbral trade-off (2 kHz dip) in stereo which I failed to notice.
 
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