PDA

View Full Version : Visual is easy, audio is not



magiccarpetride
2011-03-25, 10:41
It seems very easy to evaluate a camera or a monitor screen with regards to how realistic it is in capturing the likeness of the visible world. Take a snapshot, or record a short video clip using a camera of your choice, play it back on your TV or on your monitor, and it will be plainly obvious whether the reproduced image is faithful to the real object (in terms of proportions, visible details, texture, colors, etc.)

Things are for some reason not that easy with audio. Take a recording device, point it to the live performers, record the performance, and then play it back on your stereo. You'll realize that it's a challenge when it comes to assessing how faithful to the real sound the playback gets.

Maybe this is so because of the fact that music is fleeting? While a physical object that we just took a snapshot of still remains present, and we can compare its representation on the screen with its actual presence, we can't do that with music. Once performed, the performance is forever gone.
__________________

I'm not as think as you drunk I am!

My system: the best possible source, the best possible DAC, the best possible interconnects, the best possible preamp, the best possible power amp, the best possible speaker wires, the best possible speakers, the best possible listening room, the best possible mood for listening (and finally, the quietest possible household/neighborhood)

maggior
2011-03-25, 10:55
I'm not so sure I agree. It's happened a few times that I was at a concert and obtained an audience recording of the concert weeks after the fact. I distincly remember thinking to myself "wow, this recording very faithfully captured the sound of the performance - flaws and all".

With pictures and video, framing in addition to visual quality come into a play. Take a crappy picture, crop it to frame it more properly, and you have a totally different picture. I've experienced this myself many times.

Another thought - evaluating an audio recording in this manner is complicated by the fact that both the playback and recording setups are in play. With amateur and stealth audio recording, equipment and equipment placement have a huge bearing on the sound. A crappy recording played back on the best sounding multi-million dollar audiophile's wet dream system will still sound like crap - just very faithfully reproduced crap :-).

Yet another thought - how you feel about this depends on what "type" of person/learner you are. I am both visual and auditory, leaning toward the auditory side. Taking this into account, my thoughts on this aren't surprising. Take somebody that is very visual in their learning/thinking (as perhaps you might be) and they have a completely different opinion.

Curt962
2011-03-25, 13:09
I don't think simple comparisons are really the issue here. I think I understand what you're asking, but....something gets muddled in your query.

Does anyone here REALLY need to hold a photo up to the subject, and "compare" to see which is real?

One thing that comes to me is that we live very "sighted" lives. Nobody here would be remotely fooled by a picture, or the screen of a TV into believing for a millisecond that the image was real.

Similarly with sound. Our survival depends on determining what it was we just heard, where it is, if its getting closer, and do we need to react. This assessment occurs in a fraction of a second.....ADM not required to determine that a REAL car is about to hit us.

Your audio system might have startled you with an unexpected sound, but it has never made you fear for your life, nor elicited a survival instinct reaction from you.

Actually...mine did once, but it was when my wife found a sales receipt. Ooops. Totally different thing, but no less frightening.

There is obviously a difference, and perhaps it is one of perspective.

A guitar recorded from a microphone distance of 3" will not sound the same on your audio system, as it would if the musician sat in front of you and played. I believe this is a difference in the scale of the sound rather than any gross change in the actual sound the guitar made. It leads me to believe that there may be more to IMAX theatres, and top-end surround sound than simply larger screens, and more speakers. It completely changes the perspective of the viewer/listener...from that of an onlooker, to that of a participant.

Gotta think about this some more. Interesting conversation material though.

darrenyeats
2011-03-25, 13:18
One difference between the audio and visual worlds is that video enthusiasts are more willing to accept that measurements are useful.

As a matter of fact I was reading about projector measurements. I didn't know there are several ways of measuring contrast ratio and some are thought to be more helpful than others. Obviously measurements aren't everything - my point is, people don't get flamed on AV forums for talking about measurements.

As I wrote on another thread, for audio my opinion is that measurements on line level components are more straightforward than with rooms, speakers and power amps.
Darren

magiccarpetride
2011-03-25, 13:22
my point is, people don't get flamed on AV forums for talking about measurements.

True. My guess is that it's due to the fact that in video we don't have elusive concepts and constructs such as 'imaging' and 'soundstage'. In audio, how do you measure soundstage? Obviously, you can sit down and turn your hi fi on and play some music and 'see' the soundstage in front of you, but how do you measure it?

magiccarpetride
2011-03-25, 13:25
A guitar recorded from a microphone distance of 3" will not sound the same on your audio system, as it would if the musician sat in front of you and played.

What follows is an interesting alternative take (I'm quoting verbatim) on what you've said above (this is from another audiophile responding to my relentless trolling):

"I recall a newspaper story in Albuquerque years ago. Hudson Audio set up a blind demo - a single musician (classical guitarist IIR) and planar speakers/amps/recorder (tape IIR) all behind an acoustically transparent curtain. The musician repeatedly played for a group of listeners on the other side of curtain as well the recording of same, listeners were not told which was which. The listeners were mostly able to tell which was live vs. recording, but had to listen very carefully to distinguish, and thought the two were very close.

Hardly a rigorous scientific test, but instructive. No viewer of a still or video picture would have to pay close attention to tell if it was a recording or the real thing."

Phil Leigh
2011-03-25, 13:35
True. My guess is that it's due to the fact that in video we don't have elusive concepts and constructs such as 'imaging' and 'soundstage'. In audio, how do you measure soundstage? Obviously, you can sit down and turn your hi fi on and play some music and 'see' the soundstage in front of you, but how do you measure it?

You can't because it doesn't exist... it's 100% illusion

Curt962
2011-03-25, 13:53
It's interesting to note, that in live music "imaging" is something that is only present in the most vague sense. Being able to pinpoint a specific instrument in space amongst many is done with the eyes....or in the studio with microphone and mixing techniques. If amplification was involved, you're totally hosed.

Try it next time your at a concert. Close your eyes and see if you can tell where everyone is located on the "soundstage". Best of luck!

It really pays to calibrate the ears to reality. Audiophiles obsess over the micro-details, and manufactured, verbal measures of "the musical truth" that almost never occur in real life. It's almost as if the truth isn't good enough. We want something ever better. Hyper-truth.

Analyze and Discuss.

darrenyeats
2011-03-25, 13:59
J
(this is from another audiophile responding to my relentless trolling):
Ha ha!

I agree with Curt962's point about close-mic recordings actually. But I go along with the thrust of your post (that demo didn't necessarily use a close mic technique).
Darren

magiccarpetride
2011-03-25, 14:38
You can't because it doesn't exist... it's 100% illusion

And yet, many of us are discussing different systems that seem capable of producing differing levels of that illusion. Interesting, to say the least.

Since I'm not a photographer/videographer, I'd be curious to learn whether there is a similarly elusive, illusion-producing 'feature' in the field of visible reproduction, something parallel to the 'soundstage' in the audio world?

darrenyeats
2011-03-25, 16:39
I believe image depth (on 2D visuals) is probably the equivalent?

earwaxer9
2011-03-25, 19:42
Video is easier than audio. I like plasma. I find it more real than LCD, although LCD is catching up. With video speed is very important. In audio its more complex. Its much more than that.

MediaCenter
2011-03-28, 03:38
Audio interacts with its surrounding both at recording and reproduction stages, but video only does it at the recording stage not much at the reproduction stage.

magiccarpetride
2011-03-28, 09:49
Audio interacts with its surrounding both at recording and reproduction stages, but video only does it at the recording stage not much at the reproduction stage.

??? Ever noticed how video looks different in different lighting conditions?

Curt962
2011-03-28, 13:10
There ya go MCR....a ground floor opportunity.

"Videophile lighting products". Taking a page from the audiophile handbook, a person could make a killing with "directional" lightbulbs, Cryo filaments, and the list could go on....

Don't forget Magic Pebbles to place on top of the video monitor....huge improvements. Need a new name though...."Video Crystals" or the like.

:)

Griffin
2011-03-29, 06:44
Audio interacts with its surrounding both at recording and reproduction stages, but video only does it at the recording stage not much at the reproduction stage.

The magic words in video-land are "white balance" and "color management". Tons of interesting stuff around these issues, use google and be enlightened :-D.

During reproduction, as has been said by magiccarpetride, interaction with the environment is just as important if not more than for audio.

Unlike audio reproduction though, environment optimization for video is much easier to implement than it is for audio. Reflections can easily be seen and removed, colors can easily be measured and (provided the representation media's color gamut is large enough) adjusted for and the impact of external noise can be reduced or even completely removed by closing the curtains and switching on color calibrated lights. For audio, this often is a lot harder because a lot of trial and error is involved.

Soulkeeper
2011-04-11, 14:32
We have a tradition of looking at artificial images that strive to reproduce some aspect of reality, and suspending our disbelief. This tradition is many millennia old. In many cases, we can more easily interpret stylized images than photorealistic ones, at least partly due to this tradition. In contrast, our tradition of listening to artificially reproduced sound that strives to reproduce some aspect of reality, is hardly more than a century old (excepting the imitation of animal sounds and such, no doubt important to survival, but perhaps less important to culture).

We admitted to ourselves the futility of pursuing lifelike visuals long before the concept of lifelike audio was conceived. We understood that we had to wilfully buy in to the illusion that lines and stains on a paper could create, and we did.

Our understanding of how to listen seems less mature: We want to be fooled despite our best efforts to hear the trick. We want the illusion of sound to be perfect, like the Matrix. And that's pretty different from how we read pictures, still or moving.

Maybe because hearing isn't the primary/dominant sense of Homo sapiens. Maybe because audio technology developed so suddenly, and so impressively, that our own hubris caught us by surprise. Maybe because we feel/know that unlike the perfect video illusion, it is within the realm of possibility. I don't know which.

In the future, technology may be able to create a virtual reality that is lifelike enough to fool us. If it can do it with video, it can do it with audio, and vice versa. But that's in the future. For now, we'll just have to learn how to listen, and not least how not to listen. ;)

magiccarpetride
2011-04-11, 15:39
We have a tradition of looking at artificial images that strive to reproduce some aspect of reality, and suspending our disbelief. This tradition is many millennia old. In many cases, we can more easily interpret stylized images than photorealistic ones, at least partly due to this tradition. In contrast, our tradition of listening to artificially reproduced sound that strives to reproduce some aspect of reality, is hardly more than a century old (excepting the imitation of animal sounds and such, no doubt important to survival, but perhaps less important to culture).

We admitted to ourselves the futility of pursuing lifelike visuals long before the concept of lifelike audio was conceived. We understood that we had to wilfully buy in to the illusion that lines and stains on a paper could create, and we did.

Our understanding of how to listen seems less mature: We want to be fooled despite our best efforts to hear the trick. We want the illusion of sound to be perfect, like the Matrix. And that's pretty different from how we read pictures, still or moving.

Maybe because hearing isn't the primary/dominant sense of Homo sapiens. Maybe because audio technology developed so suddenly, and so impressively, that our own hubris caught us by surprise. Maybe because we feel/know that unlike the perfect video illusion, it is within the realm of possibility. I don't know which.

In the future, technology may be able to create a virtual reality that is lifelike enough to fool us. If it can do it with video, it can do it with audio, and vice versa. But that's in the future. For now, we'll just have to learn how to listen, and not least how not to listen. ;)

Historically, we've been enjoying trompe-l'il (lit. 'fool the eye') trickery for quite a few generations now. However, the difference is that, with trompe-l'il we walk unawares into the trick, being 'fooled', not even being aware that there is some trickery being played on us. Thus, for example, we may think that there is an extension to the room, while in reality there is only hard wall there with some smudges of paint on it.

With audio, on the other hand, we know upfront that it's a simulacrum, and yet we expect the illusion to be so strong, so powerful, that it will convince us and engross us and overpower us to the point where we forget that we're sitting in front of a machine that's producing the sounds. That's an incredibly tall order, that naive expectation of being taken for a ride and experiencing temporary amnesia. I doubt we'll ever get there.

Soulkeeper
2011-04-11, 18:54
Trompe-l'il is an interesting analogy. We can let ourselves be fooled by it for quite a while, even after we've intellectually realized it's an illusion. It's static/rigid, but it's strong. But more an installation type thing. In a similar way you can simulate rain falling on the roof by using a rainstick. That can also be quite convincing, especially if you're not familiar with the sound of rain hitting the roof of the particular building you're in.

The quest for audio/video fidelity seems to be more defined by the medium, which it seems has to be portable in some way, and versatility. If it can make a convincing simulation/reproduction of both the sound of silk hitting silk, and saluting cannons, we tend to think it's good. OTOH, if it can only show different shades of blue, we don't want to watch the latest movie on it, even if they are the richest and most varied shades of blue ever witnessed by man. Etc.

Rodney_Gold
2011-04-11, 23:25
Photography does not capture the image as we see it , there is no peripheral vision , there is a fixed depth of field and colours are dependant on monitor and printer , dynamic range is compromised as well.
You will never get the captured image as you saw it at the time.
That same image can be captured many ways , for eg with shallow DOF or with deep DOF which will change the perception/perspective , as will the focal length of the lens and so on.
There are as many ifs buts and maybes in photography/videography as there are in audio , and both encompass an objective/measurement component and a subjective side.

magiccarpetride
2011-04-12, 11:02
Photography does not capture the image as we see it , there is no peripheral vision , there is a fixed depth of field and colours are dependant on monitor and printer , dynamic range is compromised as well.
You will never get the captured image as you saw it at the time.
That same image can be captured many ways , for eg with shallow DOF or with deep DOF which will change the perception/perspective , as will the focal length of the lens and so on.
There are as many ifs buts and maybes in photography/videography as there are in audio , and both encompass an objective/measurement component and a subjective side.

You're right, photography can never come even close to how we visually perceive the world. That is the reason why visual art will never get supplanted by photography. The optical perspective, governed by the objective laws of physics, differs from the mental perspective governed by the inner laws of human psychology.

For example, if you're surveying a landscape, and then take a photo of that same landscape, you will notice that the photo doesn't match your impressions. This is due to the fact that, if you spot a large oak tree in the distance, your mind, knowing that the tree is rather large, will actually ENLARGE and augment the raw signal, so that you will perceive it differently than what the camera lens and the sensor will capture.

The above is a well known phenomenon which explains why are masterful works of art more appealing to us than high precision, high resolution photography.

Phil Leigh
2011-04-12, 11:17
You're right, photography can never come even close to how we visually perceive the world. That is the reason why visual art will never get supplanted by photography. The optical perspective, governed by the objective laws of physics, differs from the mental perspective governed by the inner laws of human psychology.

For example, if you're surveying a landscape, and then take a photo of that same landscape, you will notice that the photo doesn't match your impressions. This is due to the fact that, if you spot a large oak tree in the distance, your mind, knowing that the tree is rather large, will actually ENLARGE and augment the raw signal, so that you will perceive it differently than what the camera lens and the sensor will capture.

The above is a well known phenomenon which explains why are masterful works of art more appealing to us than high precision, high resolution photography.
...and a completely analogous thing happens with ALL of our senses.

The "camera never lies" but our senses do all the time.

Blumlein figured this out decades ago (going back to audio)... the aim is maximum suspension of disbelief - not about trying to create a simulacrum of a reality that doesn't exist anyway (as far as any of us can tell!).

magiccarpetride
2011-04-12, 11:38
...and a completely analogous thing happens with ALL of our senses.

The "camera never lies" but our senses do all the time.

Blumlein figured this out decades ago (going back to audio)... the aim is maximum suspension of disbelief - not about trying to create a simulacrum of a reality that doesn't exist anyway (as far as any of us can tell!).

It is interesting then to bring all these findings back into the universe obsessed with music. What is music? Does it have any valid biological, survival function?

If not (and I'm not aware of any counter-arguments), then, being sheer unabashed entertainment, music is a complete fabrication. Which means, unlike visual cues, or even audible cues coming at us from our immediate surroundings, music is completely non-functional, irrelevant for any biological purpose.

Being as it is, music then caters to our aesthetic sensibilities (which, as far as I can tell, serve no DNA-centric biological purpose). In which case, it gets hard to establish 'suspension of disbelief'. Disbelief in what?

RonM
2011-04-12, 11:57
It is interesting then to bring all these findings back into the universe obsessed with music. What is music? Does it have any valid biological, survival function?

If not (and I'm not aware of any counter-arguments), then, being sheer unabashed entertainment, music is a complete fabrication. Which means, unlike visual cues, or even audible cues coming at us from our immediate surroundings, music is completely non-functional, irrelevant for any biological purpose.

Being as it is, music then caters to our aesthetic sensibilities (which, as far as I can tell, serve no DNA-centric biological purpose). In which case, it gets hard to establish 'suspension of disbelief'. Disbelief in what?

The evolution of social behavior is an interesting and complex topic. Music is one aspect of social behavior -- it has to do with communication and with the development of social networks, among other things. Social functioning is hardwired into our biology (as it is for everything from bees to birds, even including slime molds). All behavioral potential has a biological function.

It is important to distinguish between experience (what we "feel") and what purpose our experience serves in an evolutionary/biological sense. We "feel" shame -- which motivates us to act in a more pro-social fashion; we "feel" happy -- which causes us to engage in additional happiness-inducing behavior; we "feel" ecstatic joy during the experience of certain kinds of music, leading us to pursue more music, and develop associated cognitive skills and engage in social activity.

The fact that our capacity for any of these feelings sometimes SEEMS to serve no immediate purpose is irrelevant. The fact that we can have these experiences flows from the evolutionary history of our species, and underlies our success as a species.

If you can call it success, I suppose.

R.

johann
2011-04-12, 12:00
The above is a well known phenomenon which explains why are masterful works of art more appealing to us than high precision, high resolution photography.

That can certainly be debated.

magiccarpetride
2011-04-12, 12:55
That can certainly be debated.

There isn't anything that can't be debated.

johann
2011-04-12, 13:14
There isn't anything that can't be debated.

LOL :)

What I meant was that a lot of people actually prefer a high-res photo of for instance a wild animal or a landscape over a painting over and old painting or sculpture.

magiccarpetride
2011-04-12, 13:36
LOL :)

What I meant was that a lot of people actually prefer a high-res photo of for instance a wild animal or a landscape over a painting over and old painting or sculpture.

I know. Also, a lot of people prefer greasy Big Mac smothered in 'secret sauce' over a scrumptious gourmet meal, but who am I to argue?

johann
2011-04-12, 14:10
I know. Also, a lot of people prefer greasy Big Mac smothered in 'secret sauce' over a scrumptious gourmet meal, but who am I to argue?

I would not compare high-res photos from Bettina Rheims, Serge Bramily, Davi LaChapelle and numerous of photographers published in for instance National Geographic, etc. to be the the Big Mac of art but each to their own.

Besides, I seem to recall that you are not that interested in food at all nor do you eat meat at all, so like you said, who are you to argue.