johnnie225
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Recorded Sound vs. the Real Thing
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What shocked me was how *close* playback came to a live demo that JA and others heard recently.

so playback sounded close to an equipment demo, wow.

KBK
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If the sound of the given instrument was recorded from about half a foot out..and then the possible dynamic range of the microphone (and room affects on such added in) was the question and answer added in, then you take the speakers and the room and enlarge them so the environment was identical to the speakers being the instrument and your ear placement being the microphone position and all else (room, acoustics, etc) scaled in size to equal that..and then you hear the guitar sounding identical to the way it sounded when your ear was at the same place as the original microphone, and listening to that same guitar---only then could you make an assessment that the given reproduction sounded the same, or not. Only then.

Hopefully someone understands my point. Making giant guitars in rooms serves little to no purpose, as weighted comparatives go. It may be fun, and we all tend to enjoy this and are sometimes surprised by the results. The whole thing is that we are trying to create the sonic illusion of the same guitar as being between the speakers but the microphone has and will always have, due to placement and other issues, have a perspective that an audio system or listener - cannot. And the recording attempt ends up requiring some sort of fabrication with regard to some form of intentional falsified room acoustics and specific aspects of microphone handling/placement.

Suffice it to say that the pressure and dynamic loading of the microphone will always be different than what the ear hears, when in the same room with the given instruments.

Elk
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I have yet to hear even a guitar amp recorded near field to truly sound like the guitar amp, even played back through that same amp.

However, a guitar recorded directly (DI - plugged directly into the board or preamp and then recorded) sounds, at least to me, essentially the same as the guitar when the recording is then played back through the guitar amp.

Microphones are imperfect transducers. They are wonderful things and a delight to play with, but they do not completely and accurately capture the real thing.

And then there is everything that comes after the microphone.

Microphones inherently color the sound. We choose microphones for their characteristics when recording. There is no such thing as a transparent, infinitely quick, flat microphone.

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Quote:

Quote:
What shocked me was how *close* playback came to a live demo that JA and others heard recently.

so playback sounded close to an equipment demo, wow.

Not an equipment demo, but a 9' Steinway D.

John Atkinson
Editor, Stereophile

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I have yet to hear even a guitar amp recorded near field to truly sound like the guitar amp, even played back through that same amp.


Well, since amps color the signal quite by design, playing it back through the same amp isn't going to help.

However, miking it close-in ignores the facts of the radiation pattern of the speakers, and that by itself is enough to toss out the idea it might sound the same.

Quote:

However, a guitar recorded directly (DI - plugged directly into the board or preamp and then recorded) sounds, at least to me, essentially the same as the guitar when the recording is then played back through the guitar amp.


Again unsurprising, you're using the original system, just with some time delay via the recording.


Quote:

Microphones are imperfect transducers. They are wonderful things and a delight to play with, but they do not completely and accurately capture the real thing.


A true understatement if I ever saw one

First, most mics, if we're not talking about soundfield mikes, capture at most 1/4 of the information (skewed in different ways, but 1/4 is the relevant result) of the pressure plus the 3 volume velocities at any given point.

Then, if we look at the coherence across space, we realize that for 20kHz, we need to sample space at every 1/2" or so in order to capture the actual soundfield. In a 1 meter geodesic around the head, this translates to "a (*(*&( lot of channels to capture".

The good news is that we can't HEAR all of that.


Quote:

And then there is everything that comes after the microphone.

Microphones inherently color the sound. We choose microphones for their characteristics when recording. There is no such thing as a transparent, infinitely quick, flat microphone.

Well, in audio terms, if we can leave very high (i.e. over 60dB unweighted) dynamic range out of it, there are mikes that do something like that in the pressure domain. Of course, we're still short 3/4 of the information at that point...

There are some words to this in the "science of audio" deck at www.aes.org/sections/pnw/ppt.htm

No need to repeat it all here, most aren't as interested as those of us who do this for a living.

Elk
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Well, since amps color the signal quite by design, playing it back through the same amp isn't going to help.

Good point. It was just yet another experiment in trying to recreate a sound.


Quote:
However, miking it close-in ignores the facts of the radiation pattern of the speakers, and that by itself is enough to toss out the idea it might sound the same.

Also true. What I meant to convey is that the room isn't playing that much of a role when one records a sound source from within three feet or so and at low to moderate levels.

Have you found anyway to mic a guitar amp and get the same sound on playback? One can get many great guitar sounds this way, but it never sounds to me like the original. Recognizable, but not the same.


Quote:
Well, in audio terms, if we can leave very high (i.e. over 60dB unweighted) dynamic range out of it, there are mikes that do something like that in the pressure domain. Of course, we're still short 3/4 of the information at that point...

A good 1/4 would be a nice place to start.

Which mics would you put in this category? I think of mics such as the Sennheiser MKH-8020 and other good quality omni SDCs as being the least obvioulsy colored.


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There are some words to this in the "science of audio" deck at www.aes.org/sections/pnw/ppt.htm

I just starting looking. Excellent stuff representing many hours of work. Thanks!

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I've got a system for my acoustic guitars called the Fishman "Aura" system. Those that know acoustic guitars with piezo transducers under the saddle at the bridge, know that they have a very nasal, "quacky" sound when run DI into a PA or any relatively clean amplification system. The Aura system is an attempt to remove that quack and replace it with what sounds like a well recorded of the acoustic output of the guitar, without the piezo pickup. What they do is have an artist play each guitar model in a studio, using a variety of mics, ranging from a Shure 57/58 up to Neuman and Schoeps studio mics. The then take the difference between the mic sound and the piezo signal to create a difference signal. The user can either send his or her guitar in for a custom set of differences or use some samples already made with most of the popular models of acoustic guitars.

The relevance to this discussion is that NONE of these sounds sound like the same guitar going directly to the ear. I love the system and love to send my guitars through the Aura and hear them as if I were sending them through a Neuman. The Neuman is richer than life, the Schoeps is drier than real and the lowly Shure is surprisingly good sounding.

None of these programs matches the real sound of any of my guitars. I can hear the acoustic character of each guitar and how they differ, but it's not the same. One of my Taylor guitars had about 12 possible mic combinations, none of which sounded like the real thing, but many sounded very nice indeed, with some sweeter than real.

I've got a CD or SACD around the house somewhere that compares around 50 mics. It's designed for use by pro audio users. As I recall, it's got a female singer and a male singer, each separately singing the same phrase a cappella each of the various mics. Of course I wasn't there to hear the singers without the mics, but the mics cover quite a range of tonal color.

Forgetting about the reproduction speakers, proximity effects, room interaction (in both the recording room and the playback room) and all the equipment in between, just the mics alone will always color reproduced sound.

I've heard lots of trumpet and acoustic guitars played in open space, with no amplification. IMHO, the sound I hear live has never been captured in a recording.

That said, I still love recordings. The very often sound better than "real", but will always lack certain aspects.

Dave

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Another thing I've notcied from doing recordings is that listening to the direct micfeed (gone through A/D converters then back to a D/A) sounded more real than the recorded version playback from hard disc. This always suprised me since there was so much A/D/A going on.

There seemed to be slightly more smear in the sound when playing the recorded version. It was very subtle, but during day three of a recording session, you begin to pick up on these things - or perhaps I lost all my marbles by that stage.

My point is, microphones are certainly imperfect, but it seems to me that transfering the live mics to a recording medium also gets in our way of the original event.

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Coolest topic in all of audio.

I can count on one hand the number of times I've been 'fooled' by recorded sound sounding live, and even then the effect was so fleeting it hardly seems fair to use it as a goal of Hi Fi!

___

You know how some native peoples believe having their image taken can rob them of some of their soul/essence? It seems recording music does exactly that - something is lost on playback that is so freaking hard to recreate it can be a little depressing.

There is also a neurologic thing that happens with being 'fooled' by a Hi Fi - as soon as we figure it out, the effect becomes ever more difficult for that system to fool you again. We accomodate so quickly to the phenomenon. I think maybe that's why some people like the sound of their rig better after a few glasses of wine or the like - the frontal lobe inhibition may help recapture some of the illusion that we have learned to squelch.

Yup, endlessly great topic, thanks for bringing it up!

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I think the strongest link of the chain is the recording medium - while not flawless we have excellent ADCs and DACs as well as a way to capture the bit stream.

The microphones and speakers (and room) are the weakest links.

Many aspects of recording are deliberately voiced - even mic preamps often have a designed in sound. Many microphones absolutely do, especially vocal mics.

It may be my classical background, but I think of recording rock/pop as much more creative as you have almost limitless choices deciding what you want a guitar to sound like, what the snare should sound like, etc.

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Quote:

Also true. What I meant to convey is that the room isn't playing that much of a role when one records a sound source from within three feet or so and at low to moderate levels.


Well,that depends a lot on the room.

Quote:

Have you found anyway to mic a guitar amp and get the same sound on playback? One can get many great guitar sounds this way, but it never sounds to me like the original. Recognizable, but not the same.

No good ones,sorry.

One of the things you need to watch out for is floor bounce changing the timbre, by the way, putting them on something that has 6" (at least) of absorbtion can help,but that also changes the sound of the amp by absorbing part of its power radiation.

When you're running an amp and a speaker into deliberate distortion for artistic purposes (and that is part of what guitar amps do on purpose, they are intended to work in that mode), things like cone flex, breakup, etc, make the radiation pattern of a loudspeaker, well, "interesting". What you hear in a hall is the power response as processed through the room's acoustics. This is what people usually regard as the sound of the amp.

That is indeed hard to capture, at least with less than a dozen microphones in an array or somthing like that, 3' from the amp.

Hard problem, you do what you can, and there really can't be a completely universal solution.

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I think the strongest link of the chain is the recording medium - while not flawless we have excellent ADCs and DACs as well as a way to capture the bit stream.

The microphones and speakers (and room) are the weakest links.


Well, that, the failure to capture the diffuse part of a sound, etc. Speakers are much worse than mikes, but it is at the mike level where we fail to capture a lot of the information.

Still, it would be possible to capture more information, but now the question of "HOW MANY CHANNELS DID YOU SAY" comes out in force.:)

Quote:

Many aspects of recording are deliberately voiced - even mic preamps often have a designed in sound. Many microphones absolutely do, especially vocal mics.


Mikes and mike techniques are very often part (and perhaps an important one in electronically produced music) of the art, as well as the engineering.

Quote:

It may be my classical background, but I think of recording rock/pop as much more creative as you have almost limitless choices deciding what you want a guitar to sound like, what the snare should sound like, etc.

We surely won't argue on that point!

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Mikes and mike techniques are very often part (and perhaps an important one in electronically produced music) of the art, as well as the engineering.

I don't think I will ever tire of playing with mic techniques, even just two-channel. The interplay between the type of mic, the venue, the postion of the performers, mic array and position - unreal how everything matters.

I also fully appreciate that I will never even vaguely master EQ, even for my modest purposes. EQ alone qualifies as a life-long study.

Buddha
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One of the greatest parts of the Stereophile Test Disc is the mic comparison.

KBK
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Quote:
Mikes and mike techniques are very often part (and perhaps an important one in electronically produced music) of the art, as well as the engineering.

I don't think I will ever tire of playing with mic techniques, even just two-channel. The interplay between the type of mic, the venue, the position of the performers, mic array and position - unreal how everything matters.

I also fully appreciate that I will never even vaguely master EQ, even for my modest purposes. EQ alone qualifies as a life-long study.

All that is why that damn optometrist is still considered to be one of the greatest recording gods, ever. (IMO)

Rudy Van Gelder.

He nailed it, every time. He's a natural. The kid (young Rudy) simply has what it takes.

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The most important thing missing from live music, is the actuality of the experience itself missing in the recording. That actual creation of the moment is immediate and visceral, and well-recorded music may maintain many of the criteria of live music, but will be always missing the 'live' piece of the equation. It's physically impossible.

If intensity has a major role, and I feel it does, the responsibility lies to a great degree with the speaker system. Being able to transmit sound across a large plane, instead of a point source, and in both directions 'equally' (read dipole or an omni to a lesser or greater extent- haven't made up my mind on that one yet), seems to me one very important criterion that planar speakers have in spades, and to me, more live as the experience's scale is an important factor in live music.

Elk
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Big planer speakers have size but, in my experience, much less dynamic range/impact.

But even before the speaker, microphones pick up relatively little of what is going on.


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The most important thing missing from live music, is the actuality of the experience itself missing in the recording.

While I guess this is inherently true, I'm not convinced that this limits our perception of recorded sound.

I don't question there is something wonderful about performing or listening to music live (I played my last concert Sunday) listening to recorded music is so different I don't miss the lack of "liveness."

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Can I just say Elk, that you absolutely rock!

Thanks for continuing this discussion Elk. It just seems that discussions sometimes devolve into something 'else', and you always propel great discussion.

Kudos, man...

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Quote:
The most important thing missing from live music, is the actuality of the experience itself missing in the recording. That actual creation of the moment is immediate and visceral, and well-recorded music may maintain many of the criteria of live music, but will be always missing the 'live' piece of the equation. It's physically impossible.

If intensity has a major role, and I feel it does, the responsibility lies to a great degree with the speaker system. Being able to transmit sound across a large plane, instead of a point source, and in both directions 'equally' (read dipole or an omni to a lesser or greater extent- haven't made up my mind on that one yet), seems to me one very important criterion that planar speakers have in spades, and to me, more live as the experience's scale is an important factor in live music.

I agree with both things you say.

Just as ambience can enhance a gustatory experience, same with Hi Fi.

There is an inherent bit of cognitive dissonance that takes place as you sit and try to enjoy an orchestra, band, or ensemble...while the lamp in your room may be where the imaging of a player issues forth!

Part of our brain, no matter how terrific the Hi Fi, is constantly saying, "This is not real, you are in your living room."

I think (pure personal opion and not meant as fact) that Glotz hits the nail square on the head when he says that the original experience is irretrievably lost, no matter how good the recording or playback chain.

I also think this is the main benefit of what we seem to like about nighttime listening - less visual noise and less disconnect between the sound and what our other senses are telling us.

__

When you think about it, even your skin gives you "audio" feedback about the listening space - there is so much for our Hi Fi's to overcome, it's amazing we get as far as we do!

___

I also agree about planar speakers and how they radiate sound as being an advantage, and I'd add that horns are likely popular for similar reasons about replicating the "feel" or "impression" we take away from live music. Sometimes, with horns, I can actually feel certain effects on my skin from how a good horn loads the air. (Hope that doesn't sound too crazy.)

I even have a favorite visual tweak I enjoy a great deal simply because it "opens up" my listening space visually, which I think helps me enjoy the listening part even more! Just as a good audio room treatment helps the walls of the room fall away, so does good attention to one's visual environment.

Part of "room treatment" should include visual cues, not only for WAF/SAF reasons, but also to enhance our own listening experience.

(Kind of like, but not in the same way, how a fine restaurant enhances one's eating experience.)

I wholeheartedly endorse trying to make the listening room itself a pleasant place to be, as a sonic tweak!!!

Post script: Likely why some people think their gear sounds better after a few cocktails, other ingestant/inhalant, or even after performing a 'listener directed' tweak - those things may help overcome that cognitive disconnect that is inherent in sitting in one's home wishing to hear Beethoven's Sixth!

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Great reply, Buddha! I approve of the visual thing having a great deal of importance. This is one of the reasons I don't want my living room to look too much like a studio. I wouldn't feel good with it, and my living room is arranged for multiple tasks/experiences, many of them not having anything to do with listening to music.

Also, being comfortable in your listening environment is a part of the visual "tweaking". Maybe this explains why listening to even great systems out of your "normal environment" not always seem to pay?

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Quote:
That actual creation of the moment is immediate and visceral, and well-recorded music may maintain many of the criteria of live music, but will be always missing the 'live' piece of the equation. It's physically impossible.

Shirley Temple to J. Edgar Hover: I don't go all the way.

J. Edgar Hoover: I don't go all the way, either.

Elk
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I think you guys are right, the visuals matter - both comfort and visual dissonance play a role. One's basic mood does as well.

vantagesc
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I'm surprised that JA's article does not discuss polar response and the limitations of most speakers in this regard.

Let me ask you a simple question. When you are listening to a live piano in a room, does it sound drastically different depending on whether you sit to the player's left or right (in front or behind of the piano itself)? It probably sounds a little different, but not all that much. Now try that with a pair of speakers. I bet it sounds way different.

I would love to see Stereophile review speakers like the Steinway Model D. Big dipoles with good polar response. I would be that the sound doesn't take on a huge tonal shift as you walk around the room, like they would with those monopoles used in the test.

I'm not saying that getting proper polar response out of speakers will solve all that ails sonic reproduction, but this is definitely a major issue. The method of placing a handful of drivers in a box has run its course...time to try something new.

KBK
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The once was story in the audio days of yore, about a person who had recorded the hard 'snick' of a set of large scissors.

They could take this recording and then reproduce it sonically...and try and record the resultant sonic hard 'snick' and look at the waveforms ..and compare.

Try as they might, even up into the 10,000 watt level on the amplification end, multiple types of amplifiers, recording, reproduction, different driver types, etc, methods....they could not get it done.

They could not get it to look the same on the scope/gear and they could not get it to sound the same. The money and minds thrown at it could not reproduce the original simple event.

The end.

Buddha
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Quote:
The once was story in the audio days of yore, about a person who had recorded the hard 'snick' of a set of large scissors.

They could take this recording and then reproduce it sonically...and try and record the resultant sonic hard 'snick' and look at the waveforms ..and compare.

Try as they might, even up into the 10,000 watt level on the amplification end, multiple types of amplifiers, recording, reproduction, different driver types, etc, methods....they could not get it done.

They could not get it to look the same on the scope/gear and they could not get it to sound the same. The money and minds thrown at it could not reproduce the original simple event.

The end.

So, if they can't do scissors, how come my Dylan records sound so much like Dylan?

I can tell it's him, every time!

I can even walk around the room and it still sounds like him.

We can be pretty fetishisitc when you think about it.

It's a fine line between being amazed that Hi Fi can do what it does and opining that it doesn't do what it doesn't do.

Didn't Klipsch, or some reviewer once do the "slamming a car door" test, as well?

KBK
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I've never had chance to hear the garage door banging that is on the HFNRR test CD. Apparently it would make people jump out of their skins.

Remember, like hearing words, and visuals, we 'pre-load' a set of sonic 'images' for faster recognition. (Like hearing a guy you THINK is Bob Dylan) Experiments in the digital telecommunications industry have shown that the human mind can integrate enough of poor quality data to achieve voice intelligibility (recognize the words) at 3.5 bits of depth in data. That..is atrociously bad. It almost makes one think that the plan with MP-3's is to debase the capacity for recognition of subtlety in the overall human system, with regard to the public masses. Audiophiles move in the opposite direction of/to extreme fidelity...but the masses are programmed to do the opposite.

The joke I was using on that one, around 1990 or so, was that sooner or later we would get a cardboard disk in the CD packaging and it would have a big 1 or 0 covering it's surface...and then that would be optimum and finally reach full efficiency and simultaneous full debasement and digitization of the human function of emotion, as tied to music. Fuck me.

To listen critically, is to listen, to some extent, with emotional involvement and hopefully with some of the mental 'pre-load' of 'sonic canvas components' - both stripped away, so we can really and fully actually listen to what is going on. Listen like a child.

I generally do both at the same time. It can be done. I listen critically to the situation for the changes I expect might be there (from the changes I made) but I'm still rocking out to what I hear. And my data set is pretty vast, from having done nothing but single cause analysis on a daily basis for the past 25 years. Yes, even on Sundays. I get itchy if I don't do at least one experiment a day. emotionally, I feel guilty as if I have shirked my duty and work. Which helps drive me to extremes. Twist your own titties, so to speak. Like most of us do, in one way or another. Perhaps you do research in your own area of expertise, every day, even if you feel as if it is some form of goofing off. But you do it regardless. Considering how you represent yourself and come across on this forum, I'm pretty well willing to bet on it.

Buddha
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I admit to goofing off every day!

You are right about experimentation - hopefully we all do some observational trials every day, with some hypothesis testing thrown in for good measure.

Elk
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Quote:
I would love to see Stereophile review speakers like the Steinway Model D. Big dipoles with good polar response. I would be that the sound doesn't take on a huge tonal shift as you walk around the room, like they would with those monopoles used in the test.

The sound of big planer speakers varies a great deal as you move around them.

Of course, part of the change is the room itself - the sound of which changes depending on where you are within it.

Then there are sounds that are nearly mono-directional such as a trumpet. The vast majority of sound of a trumpet comes directly out of the bell. Move 10 or 20 degrees off axis and the sound is totally different. Yet speakers cannot reproduce this sound well either.

Your point is good however. There is a lot about speakers which are different than the original sound source.

vantagesc
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Quote:

The sound of big planer speakers varies a great deal as you move around them.

Planar as in panel speakers / electrostats? I have never heard the Steinways and don't know if they are any good at all. But they use conventional dynamic drivers, except for the ribbon tweeter, so I wouldn't call them a planar speaker, which do indeed have the problem you describe. Based on the design of these Steinways, I would guess that they don't sound all that different as you move about the room, except you lose imaging details outside of the sweet spot. That's why I'd love to see a Stereophile review. They reviewed those $100k YGs (I was surprised at the poor distortion measurements that Soundstage took, no sure they were valid measurements) so why not.

My analogy of the piano is flawed, as you point out with the trumpet example, but the point is that all rooms have reflections, which are necessary for convincing reproduction of sound. If the speakers are energizing the room unevenly at different frequencies and in a way that excites a maximum number of room resonances / "problems", then the speakers cannot even reproduce what is on the recording properly.

This is of course only on the playback end. The recording end is a whole new can of worms.

Anyway, I think at this point all we can do is buy speakers that annoy us the least, rather than buy speakers that reproduce live sound the best.

Elk
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Quote:

Quote:
The sound of big planer speakers varies a great deal as you move around them.


Planar as in panel speakers / electrostats?


Yes.


Quote:
. . . all rooms have reflections, which are necessary for convincing reproduction of sound. If the speakers are energizing the room unevenly at different frequencies and in a way that excites a maximum number of room resonances / "problems", then the speakers cannot even reproduce what is on the recording properly.


You may well be correct that a speaker must energize the room the same as the actual instrument.

I think the bigger issue is, and I think this is what you mean, a speaker must physically produce sound as it is produced in the real world. A speaker must work like a piano, a trumpet and every other instrument in how it radiates sound.

vantagesc
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Actually, no, I'm not saying speaker should behave like instruments, though it would be cool if they could. That is an interesting supposition on your part.

I think the speaker must radiate sound in a way that allows you to hear the recording for what it is, and not hear the room. When speakers illuminate the room differently at different frequencies, we hear colorations by the room. My piano analogy was flawed and confused the issue I am trying to raise. Check out this link, the second page in particular, and the analogy of light beams: http://www.mcsquared.com/speakers1.htm

Notice how the room is "illuminated" differently at different frequencies. But you may say, well I only sit in the sweet spot, so this doesn't matter. Well it does, because you hear reflected sound too. And you can't overdamp a room because reflections are needed for proper ambiance and image retrieval. Polar response is a huge issue that few loudspeaker manufacturers address, presumably because the market wants the same kind of speaker over and over (box speakers). The best we can do is hope to hear what is in the recording and then improve our recording techniques.

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I think the speaker must radiate sound in a way that allows you to hear the recording for what it is, and not hear the room.

This would be wonderful.


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When speakers illuminate the room differently at different frequencies, we hear colorations by the room.

This makes some sense, but I am having trouble accepting separating this from the effects of the room itself as these room effects are so large.

I'm also not convinced that we need our speakers to do this. Planers/electrostatics do not sound, as a whole, any more real then cone speakers - just different and better at certain things - even thought they are vastly better at providing an even polar response. Similarly cone speakers with back and side firing woofers and tweeters don't sound "better" overall.


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And you can't overdamp a room because reflections are needed for proper ambiance and image retrieval.

People often state this, but I have yet seen the foundation for it. I believe this is an assumption.

A performing space or recording space needs a certain level of ambiance to be pleasing to the ear. But the best sounding rooms for reproduced sound have no sound of their own; they take the room out of the equation.

I think the only reason that a room could possibly sound overdamped (I have yet to hear one on playback) is that the recordings we listen to are mixed and mastered in rooms that have some degree of reflected sound. That is, a certain amount of reflection is "assumed."

The best rooms for image retrieval and ambiance playback are those where the room itself imparts no sound, no coloration.

Get rid of all reflected sound in the rooms used in the production chain and I bet we will want "overdamped" rooms for playback. Recordings will be made with mics placed for more indirect sound, more reverb will be used in pop and rock recordings (heaven forbid), different EQ will be employed, etc.

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This makes some sense, but I am having trouble accepting separating this from the effects of the room itself as these room effects are so large.

Which came first, the chicken or the egg? Since almost all speakers we listen to have poor polar response, rooms only serve to exacerbate the problem. I think we are in agreement on the problem that must be solved. You fix the room, you fix the speaker, or maybe you fix both. Depends on your opinion of the problem. My feeling is that I want to listen to music in my living room, not a chamber. So I think we might as well buy speakers with proper polar response.


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I'm also not convinced that we need our speakers to do this. Planers/electrostatics do not sound, as a whole, any more real then cone speakers - just different and better at certain things - even thought they are vastly better at providing an even polar response. Similarly cone speakers with back and side firing woofers and tweeters don't sound "better" overall.

Planar speakers only have proper polar response at low frequencies, where they are limited in SPL. At higher frequencies they are directional just like standard speakers. Their dynamic range as a whole is also problematic.

There are a lot of variables to how a speaker will sound in the end, but a true bipolar speaker with an acoustical short circuit arguably has better polar response than a standard speaker. Just because you have a rear firing tweeter or side woofers doesn't mean the speaker has proper polar response.


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People often state this, but I have yet seen the foundation for it. I believe this is an assumption.

Frankly I don't know enough to comment further, other than that I don't think many people are trying to listen to speakers in anechoic chambers, for whatever reason. I would also speculate that in a completely damped room, all you are going to be hearing is direct sound from speakers. If you only have two speakers, our brains won't necessarily process this correctly. You would then need more than 2 speakers. Think about headphones and the auditory image they provide.

If you have some time, I would encourage you to listen to Mr. Linkwitz (of the Linkwitz-Riley crossover) and his hypothesis on sound reproduction. I find it interesting:

Part I of his speech here:
http://www.youtube.com/watch?v=VC-sxvNzC8I

Text here:
http://www.linkwitzlab.com/stereo%20reproduction.htm

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My feeling is that I want to listen to music in my living room, not a chamber. So I think we might as well buy speakers with proper polar response.

Even with perfect polar response speakers the room will have a larger impact on the sound until the room is exceedingly well treated.


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Just because you have a rear firing tweeter or side woofers doesn't mean the speaker has proper polar response.

No disagreement. However such speakers move toward polar response and yet do not sound appreciably more "real."

Similarly speakers such as Magnepans radiate pretty much equally to the back as the due the front in all frequencies (they have a figure eight polar response).

They do not sound appreciably more "real", just different. (Great speakers however, especially with transients).


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I would also speculate that in a completely damped room, all you are going to be hearing is direct sound from speakers. If you only have two speakers, our brains won't necessarily process this correctly. You would then need more than 2 speakers. Think about headphones and the auditory image they provide.

One would hear only that which comes out of the speakers. However the image is very different from headphones as both ears hear sound from both speakers (which headphone amp cross feed features attempt to solve).

To get a real sense of the space and a true life-like image we need many microphones and many corresponding speakers. Microphones capture very little of the soundfield and speakers similarly reproduce very little.

We cannot get this through sound bouncing of a room's walls. While this can provide a sense of spaciousness it is room dependent and has nothing to do with what is on the recording.

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I think open baffle speakers with dynamic drivers might have advantages, but it's possible that they add more "ambience" that what the recording engineer heard. I'd also like to try line sources. It seems that the ideal speaker would be a point source that radiates equally in all directions.

You might find this interesting:
http://blog.ultimateavmag.com/ultimate-tech/true_stereo/

This idea has some real potential IMO.

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This looks like great fun!

I would love to hear what this is like, especially on a two channel source that I know well.

I can understand enjoying the sound of open baffle speakers. My first serious speakers were a pair of Dahlquist DQ-10s.

The fact that some prefer a difuse sound field v. a precise sound filed begins with the original recording technique. Some prefer the openness and diffusion of spaced omni mics; others prefer an X-Y pair. Some are in-betweeners and go with ORTF. Whatever sounds best to you rules.

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With some recordings, my small 2-way monitors seem too laser sharp in imaging. With some recordings, my dipoles seem too diffuse. You can never win.

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Exactly!

I have a recording project where one of the members of the musical group has a excellent high resolution system - digital amps, Maggie 3.6s, etc. Another member's system is all about texture and timbre (tubes, etc.).

The high resolution guy keeps wanting a more diffuse recording and more room sound. The texture guy wants more direct sound.

I am convinced they both want the same sound.

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Have you found anyway to mic a guitar amp and get the same sound on playback? One can get many great guitar sounds this way, but it never sounds to me like the original. Recognizable, but not the same.

Ive found a good approximation, yep. I use a condensor(typically a u87 ) pointed on axis on the speaker that sounds the best and a dynamic(I like the transformer modded sm57) off axis...right beside the condensor)


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Which mics would you put in this category? I think of mics such as the Sennheiser MKH-8020 and other good quality omni SDCs as being the least obvioulsy colored.

I would put my josephson c617 with gefell mk221s, the sanken cu-100k (freq response 20 Hz- 100kHz) and the sonodore mics up there.... my c617s are amazing.

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I forgot to mention that that the two installations of the "true stereo" setup mentioned in the article are here in Los Angeles. I ought to go check it out!

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Taras has built anehcoic chambers before and listening to the blood moving in your neck and head is not at all that pleasant. It really reminds you of your mortality, and is quite distracting.

It also makes you feel as if you head is going to explode from the pressure. You can also clearly hear the voice coming off a person's chest, as well as your own voice doing the same. A good place to do drugs, for the over the top twist...but only for a few minutes! You would not want to be tied up in there in the dark.

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I would put my josephson c617 with gefell mk221s

Yes!

Wonderful mics.

Color me jealous.

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It also makes you feel as if you head is going to explode from the pressure.

Interesting. My reaction is the opposite. It feels like something is being sucked out of my head; the "pressure" is decreased.

I have the same reaction to well-damped rooms and studios. My guess is that there is less reflected sound and thus it feels like the room moves outward.

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I forgot to mention that that the two installations of the "true stereo" setup mentioned in the article are here in Los Angeles. I ought to go check it out!

Go and let us know!

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It also makes you feel as if you head is going to explode from the pressure.

Interesting. My reaction is the opposite. It feels like something is being sucked out of my head; the "pressure" is decreased.

I have the same reaction to well-damped rooms and studios. My guess is that there is less reflected sound and thus it feels like the room moves outward.

I think we both mean the same thing, your wording is more explanatory.

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I hope I didn't appear to be correcting you. I'm not.

We are describing the same exposure to a unique type of space, but we may subjectively experience it very differently.

It took me a while some time ago to describe the physical sensation of entering well-damped rooms. It isn't unpleasant, but it is different.

Neat stuff.

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That's what I mean. the pressure isn't in the room, as there is seemingly none on the room, the pressure is suddenly in your head and trying to equalize against the lower pressure in the room.

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If there was NO PRESSURE in the room, YOU WOULD EXPLODE!! Maybe you need a decongestant and a science book.

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That's what I mean. the pressure isn't in the room, as there is seemingly none on the room, the pressure is suddenly in your head and trying to equalize against the lower pressure in the room.

Exactly.

Interesting that we have the same subjective experience. I haven't asked others their sensation - I will now.

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It feels like you want to clear your ears, like when flying or experiencing a head cold. Too damped is lousy for listening. By the way, my response to KBK was a joke...I think alot of my attempts at humor will not translate well to this format:O)

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