The Sound of Live Music

I think that we need to consider that using the term 'clean' to describe a deficit may do some disservice to one its many meanings of 'lack of impurity'. If distortion is considered a deficiency 'cleanliness'(a lack of impurity) should be thought of as a goal rather than that which was to be avoided.

I would guess Al that what you are attempting to convey is the tendency of a lesser resolving system to 'paper over the cracks'. To hide flaws. The be unable to reveal deficiency. That attribute can at times be regarded as a plus, by some, however I feel that the ability of a system to present the recording as it is 'warts and all' to be the goal of high fidelity. The audio system equivalent of the soft-focus lens does make the relatively unpalatable more presentable, however at the same time that type of system reduces that which can be ascertained from the best recordings.

Pleasurable is in the ear of the beholder. If the goal of life is to never listen to anything that one finds 'objectionable', then one would have to stop listening to Life in general, since Life serves-up what it will and we subsequently decide whether what we are hearing is pleasurable or objectionable. Assembling a system to render recordings 'pleasurably' means tailoring the already fixed sound of the recording according to one's individual bias. That's fine by me. If one wants that, by all means go ahead with my blessing, but any person who takes that path can't tell me that it is high fidelity. It is diverging from high fidelity to suit one's personal preconceived taste. Diverging from high fidelity to arrive at a place where the difference between the better and the less good recordings is less obvious. All that, in order to make the less good recordings more 'pleasurable' according to that individual's preconceived bias of what determines pleasurable. If in the process the greatest recordings lose a portion of just what makes them great, just what actually distinguishes them as great, has that which is truly 'great' as a recording really been well served by that action?

As much as we do indeed listen to music for pleasure, isn't it true that the actual sonic advancements of replay systems of the last 80 years or so now reveals the deficiencies of recordings made prior to 1930? Should we take the attitude that since our modern systems show those recordings to have flaws, that revelation is not progress? No, we acknowledge that those recordings have some flaws due to the limitations of the technology of that time and we also acknowledge the implicit fact that the best systems of today are more capable with better modern recordings. It is perfectly natural that a better system exposes flaws in 80 year old recordings because it also allows greater access to the virtues of the modern recordings. The better modern recordings are incapable of being completely appreciated if they were replayed on a system which would totally mask the limitations of an 80 year old recording. Honesty to the limitations of the recording is not a negative unless one finds the truth of what is on a recording a negative. Really we all want to hear more of the truth of live un-amplified sound. The sound of real instruments as they sound in real life. That is The Gold Standard for recorded sound. Devising systems which reveal less or systems which tailor the sound to cloak flaws in such a manner which suits some arbitrary bias of what makes my recordings sound good to me, can't be the way to make progress toward advancement in capturing the honest sound of real life.

Consider the wide difference in the presentation of sound which one experiences when one goes to listen to what is touted as high fidelity sound. There are systems which are comprised of low wattage single ended triode amps coupled with speakers which consist of one crossover-less full range driver. There are very tall line source speakers comprised of multiples of drivers which require hefty amps to drive them. There are planar speakers. There are Horn speakers. Compression divers. Dynamic drivers. Ribbons. They all sound markedly different. Why is that? If truth is what they all presented, wouldn't they all sound alike? Or are there fifty versions of the truth? I know that if I was inquiring about some determinable concept like the volume of a bottle, I wouldn't give credence to any method of determining that which gave fifty different results. Yet that is where we are at with high fidelity sound reproduction. Differing 'schools' of What Is Right each with their own acolytes who proclaim that the approach that they espouse as correct and the other approaches are less truthful. They can't all be truth. They all present a given recording differently. Here the term 'pleasurable' really finds its full bloom. With each adherent to their chosen 'accepted' style of presentation finding it only pleasurable. To the exclusion of the way that 'other' types of system present recorded sound.

Could it be that some of those systems 'distort' the truth of what is on the recording in such a manner as to suit the preconceived bias of what that individual finds 'pleasurable'? Since they all present given recordings differently, it is difficult to escape the conclusion that at least some of those approaches cannot be presentations of what the recording actually is in truth. So are we seeking to hear recordings for what they are or are we seeking to hear what we want to hear? Live un-amplified sound is what it is. The sound on a recording, which by its very definition is not live, is what it is. Should we be seeking to hear things as they are? Is there an approach to system building which more closely approaches presenting recordings as they are?

That remains the question.

Al M. said:

By the way, what holds for reproduction of unamplified live music, may hold for reproduction of amplified music as well. I remember a report of a session at a dealer where they played some tracks of a live album by Eric Clapton (from CD). On one system that was considered very good the guitar was very clean sounding. Yet then the music was played on a much more expensive system and the writer of the report gushed how now the guitar sounded much more raw and grungy, like what you would expect from a live electric rock guitar. So this implied that while the first system was impressive, it was actually too clean sounding.

***

I remember that I had to chuckle in amusement when I read that report (more than two decades ago), because on my own system electric rock guitar also sounds raw and grungy and I said to myself, so then you insinuate that you have to spend so much money on a sound that I can achieve at home at a fraction of the cost? My system had always sounded good on E- guitar, and just recently an audiophile who himself had played in a band commented how great the electric guitars on Hells Bells by AC/DC sounded on it. The system may have a number of weaknesses but a generally too clean sound is probably not among them...

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Not all electric guitar sounds raw and grungy. Not all Eric Clapton tracks do either. Whether or not this is a good judge of system performance is really hard to judge without referencing specific recordings.

Tim

theofile: fantastic post.

I've been thinking a lot about this subject lately as I try to optimize & critique my system.

I remember the first time I auditioned a Pass Labs X-15 phono stage. I rejected it because I didn't like how it sounded on electric guitars. I might have even played AC/DC (not sure, it was some years ago). Ultimately I thought it was robbing the guitars of their grandeur, that they didn't sound like I thought they would/do in real life, nor how they seemed to come across on lesser systems including car stereos.

Now certainly important or vital aspects of an instrument can be lost when recording (recording is a lossy affair) and therefore the persons at the wheel try to capture the event in such a way, that when played back through the target systems of the day, they convey the elements most important to them. Part of this loop can involve the distortions that a typical system brings to the equation. This can be as simple as frequency response. For example, if most systems of the day had a huge mid-bass hump then engineers may present the final mix as lean so that it doesn't sound muddy on the typical system. You play this back on a system with a fairly flat frequency response and it doesn't have the power or slam that was intended by the artist(s).

I think it gets trickier with digital (which imo is much more lossy than analog). If one has a system that is squeaky clean and honest, the 'cracks' are revealed and it will really depend on the recording/mastering as to whether something will sound correct on many systems.

MadFloyd said:

theofile: fantastic post.


Now certainly important or vital aspects of an instrument can be lost when recording (recording is a lossy affair) and therefore the persons at the wheel try to capture the event in such a way, that when played back through the target systems of the day, they convey the elements most important to them. Part of this loop can involve the distortions that a typical system brings to the equation. This can be as simple as frequency response. For example, if most systems of the day had a huge mid-bass hump then engineers may present the final mix as lean so that it doesn't sound muddy on the typical system. You play this back on a system with a fairly flat frequency response and it doesn't have the power or slam that was intended by the artist(s).

I think it gets trickier with digital (which imo is much more lossy than analog). If one has a system that is squeaky clean and honest, the 'cracks' are revealed and it will really depend on the recording/mastering as to whether something will sound correct on many systems.

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MadFloyd and theofile,

Two nice posts. Thanks also to Al M. for reviving this most interesting thread. theofile asks an interesting question. I would answer by writing YES, there is an approach to system building that gets us closer to presenting the recordings as they are. But somewhere earlier in this excellent post is a reference to the Gold Standard and trying to reproduce what unamplified instruments actually sound like. High fidelity to the recording and music sounding real are not the same thing.

So, my interest, and what I am trying to learn, is slightly different from what theofile asks. I agree that there are two approaches: pleasurable sound or high fidelity to the recording. I have been thinking more about this ever since the suggestion to directly compare MadFloyd's analog to digital sources came up. One can compare the two sources to determine which one is personally more pleasurable. Whether that is also which one is "better" or which one more accurately portrays what is on the recording is a different matter.

"Better" may mean, "I prefer it". Or "better" may mean it is more faithful to the recording, or "better" may mean it sounds more like real instruments. Mixed up in all of this are two other direct comparisons that have been discussed recently. Is the digital recording of the LP indistinguishable from the LP itself, AND, does the LP or the digital file more closely resemble the mic feed?

So, as I see it, there are three comparisons which need to be made, and the results will get us closer to the question which theofile asks at the end.

1. How do the LP and digital file of the same recording compare to the original master from which the recording was made? And does it make a difference if the original master is analog tape or digital file?
2. Is a digital file of an LP needle drop indistinguishable from the LP itself?
3. Does a 45 RPM Direct to Disk LP or a quad DSD (or other digital format) sound closer to the direct mic feed or the actual musician playing the instrument?

We assume that if the technology makes a perfect copy of something, that it is transparent. However, transparency does not guarantee that it sounds real. I don't think we yet understand everything we need to know to make an audio system sound real. Is this not obvious from the point that theofile made regarding the fifty or so different takes on real sound.

Another side discussion is whether or not there actually is "an absolute sound". I have heard specific instruments and halls all sound different depending on many, many conditions. Which is correct? Al M. has written about, and I have discussed with him, the notion that there is no absolute sound. There is instead a range of sounds from any given instrument in a give hall, and if a system can reproduce the sound within this band, then that system can sound convincing, believable, natural, or what have you. This is the sound that we have all heard live, and we know that range when we hear it. It is our reference and what convinces us of the success of a system. Reproducing a sound within that range, which can vary considerably, is the actual goal, in my view.

Also interesting is MadFloyd's comment above that digital is a lossy recording technique. This was once assumed, but has recently been forgotten or is thought to have been corrected with the latest digital technology. Ian has been living with quad DSD and listening to it for a while now. And he seems to find it lacking in certain ways that analog is not. I happen to also think that both digital and analog are lossy, and they each lose different aspects of the sound. It is complicated and I'm sure controversial, but understanding this and how to improve it are critical to being able to reproduce music which is convincing.

So, back to theofile's question: Is there an approach to system building that gets us closer to presenting the recordings as they are? Yes, there is, and it is different for all of us. But I am increasingly convinced, that this is not necessarily the approach to getting our systems to sound more like real instruments? For that, I think that we have to answer the three questions I ask above and see where that takes us.

PeterA said:

MadFloyd and theofile,

Two nice posts. Thanks also to Al M. for reviving this most interesting thread. theofile asks an interesting question. I would answer by writing YES, there is an approach to system building that gets us closer to presenting the recordings as they are. But somewhere earlier in this excellent post is a reference to the Gold Standard and trying to reproduce what unamplified instruments actually sound like. High fidelity to the recording and music sounding real are not the same thing.

So, my interest, and what I am trying to learn, is slightly different from what theofile asks. I agree that there are two approaches: pleasurable sound or high fidelity to the recording. I have been thinking more about this ever since the suggestion to directly compare MadFloyd's analog to digital sources came up. One can compare the two sources to determine which one is personally more pleasurable. Whether that is also which one is "better" or which one more accurately portrays what is on the recording is a different matter.

"Better" may mean, "I prefer it". Or "better" may mean it is more faithful to the recording, or "better" may mean it sounds more like real instruments. Mixed up in all of this are two other direct comparisons that have been discussed recently. Is the digital recording of the LP indistinguishable from the LP itself, AND, does the LP or the digital file more closely resemble the mic feed?

So, as I see it, there are three comparisons which need to be made, and the results will get us closer to the question which theofile asks at the end.

1. How do the LP and digital file of the same recording compare to the original master from which the recording was made? And does it make a difference if the original master is analog tape or digital file?
2. Is a digital file of an LP needle drop indistinguishable from the LP itself?
3. Does a 45 RPM Direct to Disk LP or a quad DSD (or other digital format) sound closer to the direct mic feed or the actual musician playing the instrument?

We assume that if the technology makes a perfect copy of something, that it is transparent. However, transparency does not guarantee that it sounds real. I don't think we yet understand everything we need to know to make an audio system sound real. Is this not obvious from the point that theofile made regarding the fifty or so different takes on real sound.

Another side discussion is whether or not there actually is "an absolute sound". I have heard specific instruments and halls all sound different depending on many, many conditions. Which is correct? Al M. has written about, and I have discussed with him, the notion that there is no absolute sound. There is instead a range of sounds from any given instrument in a give hall, and if a system can reproduce the sound within this band, then that system can sound convincing, believable, natural, or what have you. This is the sound that we have all heard live, and we know that range when we hear it. It is our reference and what convinces us of the success of a system. Reproducing a sound within that range, which can vary considerably, is the actual goal, in my view.

Also interesting is MadFloyd's comment above that digital is a lossy recording technique. This was once assumed, but has recently been forgotten or is thought to have been corrected with the latest digital technology. Ian has been living with quad DSD and listening to it for a while now. And he seems to find it lacking in certain ways that analog is not. I happen to also think that both digital and analog are lossy, and they each lose different aspects of the sound. It is complicated and I'm sure controversial, but understanding this and how to improve it are critical to being able to reproduce music which is convincing.

So, back to theofile's question: Is there an approach to system building that gets us closer to presenting the recordings as they are? Yes, there is, and it is different for all of us. But I am increasingly convinced, that this is not necessarily the approach to getting our systems to sound more like real instruments? For that, I think that we have to answer the three questions I ask above and see where that takes us.

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Keep in mind, that without the original R2R machine and master tape the digital copy was made from to compare the digital to, nobody is in the position to judge which format is lossier than the other subjectively. Subjective preference maybe, but transparency is another story.

The man who made those quad DSD recordings was at the studio involved with the mastering process. He likely has a pretty solid opinion of how lossy the transfer was.

Al et al (!) thank you for reviving this thread. I'm not sure how I missed it the first time around, but I'm glad to see it now.

The gap between live and recorded music is a topic we've all touched on before, but I suppose I'm becoming increasingly interested in the *perception* of accuracy in an ultimately flawed recording and playback system, rather than the more objective question of accuracy itself. Obviously "getting as close to what's on the recording as possible" is the ultimate goal, but while I aspire to SOTA playback at home I don't have the funds, room or time to attain it. I also think that a lot of the arguments here are due to the assumption that actual accuracy and perceived accuracy are the same thing. I don't think they always are, but that's probably another story.

Anyway, can I share an anecdote? There was a sound I used to hear on some recordings at home, a hard, nasal, honky sort of sound in the upper midrange, and it used to drive me mad. It was as if a certain narrow range of frequencies was smearing together and building on itself, robbing the sound of clarity and introducing a distraction that, once heard, was hard to overlook. I obviously assumed it was a recording or playback failing and ignored CDs that displayed the problem excessively. However, one particular day I found myself at a smallish local venue listening to a young baritone. He was singing from an organ loft into a small space with quite a dry acoustic, and at some frequency ranges I heard that EXACT distortion that was so irritating to me at home. It got me thinking about the nature of reality and what we're trying to do here.

I brought a fellow hifi nerd to another live and unamplified gig at a different venue at around the same time, and he was looking forward to hearing sax and piano and other bits and bobs up close and personal. At the end of the concert he expressed his disappointment at the lack of leading-edge definition to the sound, the lack of imaging and the lack of air around instruments. We were only around 25 or 30 feet away from the performers and the acoustic was fairly unobtrusive again, but for him the experience in purely sonic terms was lesser than sitting in front of his hifi.

In both of these cases, a recording and playback system that accurately captured and reproduced the sound from our seats would be low on "perceived" accuracy, and might even be considered coloured, dull, dark, distorted or any other of those negative things that we read in reviews. In the first case, a system that smoothed over details and masked that distortion might be considered more accurate sonically to a listener who hadn't been there. In the second, a system that added a bit of top-end sparkle and maybe tilted up the tonal balance a little might be perceived as more accurate.

Where does this leave us as listeners? Well, at the very least it allows us to argue over what "accurate" means!

Been performing and listening to live classical all my life and don't recognise this supposed "distortion" in classical music. Not sure what you are meaning here at all.

Al M. said:

In my opening post I have described two instances of it, one from a jazz concert, another one from an orchestral one.

Diapason, who is also a musician, appears to recognize the phenomenon, otherwise he would not have encouraged me to post on it (see # 41). I am not claiming that it happens all the time since often live sound is indeed smooth.

Having said that, I don't doubt your experiences, especially since different people appear to perceive things differently; this of course holds generally in life.

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Al - what do you mean? What are you hearing?

This is a great discussion. I'll give another example of the sound of live music that really surprised me and reminded me of something I actually hear through stereo systems in some rooms. It was while listening to solo cello in a living room setting in one of the great houses in Boston. I was with Al M. listening to these sonatas of cello and piano. When the cello played alone, and Al and I moved slightly to a different seat in the audience, there was the very clear perception that we were sitting in a bass node. Certain bass frequencies were increased in volume relative to others, and it sounded decidedly less smooth, almost distorted. Here is a photo from that performance:

Al M. said:

In the above post Peter describes certain sounds due to room interactions as "decidedly less smooth, almost distorted". What I describe as distortions in my opening post also seems to be mainly due to acoustic interactions of sound sources with the hall, but then at higher frequencies.

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Hi Al,

I’ve mentioned this anecdote before, so forgive me for mentioning it again here.

Many years ago I bought Erkki-Sven Tüür’s Crystallisatio on ECM (1996). During "Requiem", a piece for mixed choir and orchestra, there appeared to be a distortion on loud sustained peaks during the last couple of minutes. At first I thought it might be clipping, either at the mics or the pres/converters (it’s a DDD release). I put it down to an unfortunate recording, and moved on.

Years later, attending a choral concert for massed mixed choir, I experienced a similar thing. I have played music most of my life. I began singing in the choir as an eight-year old and since then have played in bands not limited to wind band, jazz band, brass band, orchestra and latterly, indie/rock/pop/alternate bands. I then spent time recording and producing. So I’ve been aware of situations in which the sheer sound pressure level causes temporary tinnitus and pain. This was not that “sound”.

I’ve thought about this a bit, and it’s interesting others have described something similar. We know that the outer and middle ear’s transfer function gives a peak sensitivity to frequencies roughly between 1kHz and 3kHz (i.e.; between B5 and G7). While most music doesn’t always occur in that range, the second and third harmonics of a 440kHz tone (A4) will be 880Hz (A5) and 1.320kHz (E6) respectively. So it’s fairly easy for a simple piece of music to be spectrally located within 1kHz to 3kHz depending on the instrumentation, even if sparsely scored. We also know what the ear “hears” is not the same as what the brain “listens” to - the former only relates to the movement of air, the latter to the process of perception.

But it puzzled me that it was during listening to choral music I experienced this. Yes, a stack of cranked Marshalls and a beaten-to-within-an-in-of-its-life hi-hat can be an intense pain in the ears after only one song (a distorted electric guitar amp produces harmonics wholly disproportionate to the instrument itself when played acoustically - that’s obviously what’s great about that sound). But again, this is not that sound. It got me thinking about the uniqueness of the human voice and particularly, what happens when you group the human voice together in unison.

Any tenor will, despite the fact that he will sing in roughly the same range, have a unique timbre to his voice that differentiates him from another tenor. If our tenor sings A4, it will be distinguishable from the other tenor who sings the same identical note by virtue of the fact that their tone and therefore, the harmonics generated from the A4 note will vary in degree relative to each individuals unique physical attributes and vocal technique (pitch accuracy, vibrato).

So, leaping into the utter unknown here, I’m wondering: Is what I experienced in the above two instances a form of acoustically-produced intermodulation distortion whereby the combined harmonics and wavering of pitch and modulation causes a “distortion” of the same note when sung in unison, exacerbated by the venue’s acoustics and various nodes peaking in the range of the ear’s greatest sensitivity? (That is, is it something specific to the anatomy of the ear, rather than something specific to our perception...)

I mean, I have no idea. It’s a guess, right?

But I haven’t experienced it on any other form of music - only choral - and only on loud peaks of sustained unison singing. Not from drums, or orchestras, or dark-ambient metal, or Sun Ra.

And, er, that’s it. Sorry, that’s all I got. May greater intellects than mine shine light on our quandary.

Al M. said:

Thank you very much for this fascinating and enjoyable post, 853guy.

You may be onto something with your intermodulation distortion hypothesis.

My live experiences with choir music have included enormously clean sounding music, and in two instances, when I sat close to the stage with a large choir, it was also enormously powerful and really, really loud, all while maintaining that enormous cleanness of sound. Yet on other occasions I have also heard rather 'grating' sounds from live choir, including instances where I heard things similar to what you describe. It all depends on acoustics, seating and the harmonies sung.

Just a few months ago I heard some surprising hardness of sound, from a local, rather small choir singing in a small hall. More recently later in the same hall and with the same choir, it did not sound as hard, but my seating in the hall was different.

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Hi Al,

Well, I think it's a really interesting subject.

Looking at some older research (Ballachanda: 1997) suggests the greatest pressure gain in the ear canal due to its shape, length and natural resonant frequency (four times its length - making it a quarter-wave resonator) is in the region of 2kHz to 4kHz at 10-15 dB, while the peak increment is at 3kHz for a maximum of 17-22 dB. So it seems for a given ear canal length of 25mm (the average for an adult male), one can then calculate ear canal resonant frequency by using this equation: f = c/(4xl), where f = the resonant frequency, c = the velocity of sound in air, and l = the length of the air canal. So for an average adult male whose ear canal is 25mm in length, we’d get f = 34400/(4x2.5) which gives a resonant frequency of 3.4kHz.

So again, perhaps this phenomenon is related to harmonics occurring in the range not only of the ear canal’s greatest pressure gain, but also of its natural resonant frequency. Perhaps that’s also why some experience it and some do not, due to the variance of the individual’s ear canal shape, length, and the point at which the sounds are received at the ear and the combination of the even- and odd-harmonics of the musical spectra exacerbated by the room.

Again, guessing.

Al M. said:

What is strange, and I don't know what your experience is with it: sometimes these things, the hardness and the 'distortion' are very evident with me just sitting there in a concert, but often I hear them only with eyes closed. Take that choir in the small hall that I just described. With eyes open the sound seemed very 'clean', but when I closed my eyes I noticed that hardness and the apparent reflections from the walls that seemed to be the cause. I notice that rather pronounced difference in perception with eyes closed versus open quite often. It seems that the sense of hearing is distracted from perceiving these things when the brain receives visual clues from seeing the musicians perform at the same time. Or perhaps it's just me; in any case I'd suggest to everyone to try if your perception of the sound changes with eyes closed during a live performance. Listening with eyes closed also seems the fair comparison with what I would hear from my stereo system when listening in the dark, which I usually do. But even when I have my eyes open at home they do not receive any visual clues from performers, at least not when I listen to my system. When I am watching video of a musical performance I only do that on the computer with headphones.

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Well, that would seem to concur with the current research (Vines, Krumvansl, Wanderley, Dalca, Levitn: 2010 ) that seeing a performance, as opposed to just hearing it, may lead to an increase of positive versus negative emotions in the listener, irrespective of whether the physical performance of the musicians is animated or subdued. Interestingly, evidence was found to support the theory that music has the potential to generate multivalent emotional states in which positive and negative emotions co-occur, much like life.

Perhaps we are more susceptible to negative emotional states when deprived of the ability to see, and hence, perhaps more able to be influenced by sonic anomalies (distortion, odd-order harmonics, etc) than we would otherwise.

EExtremely interesting discussions!

My $.02:

The physical space in which the music is performed has perforce an impact on the sound we hea. Yes! One can sit at the wrong place in a live performance. However much current days audiophiles want to push away Science it is all there; You will not escape the Laws of Physics by denying their existence.

The recollection of Al. M and Peter A. is just an example of small room acoustics at works IMO: Room modes dominate ins those small rooms. Same in our listening environment. Most (All) living rooms obey to the laws of small room acoustics. Whether the sound producer is a speaker or an instrument the results will be similar. I would suggest that the studies cited above (Vines, Levitin et al 2010) could IMHO be extrapolated to the tendency to hear positive things about certain systems or components when the reputation/price/prestige is known. Said perception consistently become different (more accurate?) once knowledge is removed..

FrantzM said:

EExtremely interesting discussions!

My $.02:

The physical space in which the music is performed has perforce an impact on the sound we hea. Yes! One can sit at the wrong place in a live performance. However much current days audiophiles want to push away Science it is all there; You will not escape the Laws of Physics by denying their existence.

The recollection of Al. M and Peter A. is just an example of small room acoustics at works IMO: Room modes dominate ins those small rooms. Same in our listening environment. Most (All) living rooms obey to the laws of small room acoustics. Whether the sound producer is a speaker or an instrument the results will be similar. I would suggest that the studies cited above (Vines, Levitin et al 2010) could IMHO be extrapolated to the tendency to hear positive things about certain systems or components when the reputation/price/prestige is known. Said perception consistently become different (more accurate?) once knowledge is removed..

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Hi Frantz,

That would invoke expectation bias. The study above was specifically related to the physical performance (body language) characteristics of the performers, and whether that made a difference to the emotional state of the listener. They discovered the most significant variable was not whether the performer telegraphed emotional intention through body language to differing degrees, but simply whether the listener could see the performance or not.

It would be interesting to know whether sighted vs. non-sighted listening and its effects on the perceived emotional state of the listener would come to similar conclusions, though I'm not aware of any research on this.