Moulton Laboratories
the art and science of sound
The Microphone vs. the Ear
Dave Moulton
May 1993

Why Recordings Don't Sound Quite Like the Real Thing and Some Things You Can Do About It. An informal introduction to the realities of psychoacoustics.

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The Microphone vs. the Ear

The Problem

Like our health, we take our hearing for granted, except when something goes wrong. This is especially true with music, which is such powerful stuff that when we are experiencing it, we pay little attention to either the medium carrying it (sound) or the system through which we are experiencing it (our hearing). Usually, our perception of music is so solid, convincing and satisfying that the physics of the system disappear.

This gets us into trouble when we try recording. The sound of the music is quite palpable and solid when we listen to it, but after we record it and play it back, we often are quite disappointed with what we've lost. In even the best of cases, we notice that the music is different -- the playback doesn't sound the same as the original. The sounds we heard in the studio when we were setting up the microphones don't sound the same coming out of the loudspeaker.

If you read the advertising for recording equipment, you've probably noticed considerable hype about realistic and accurate sound reproduction. Microphone and loudspeaker manufacturers breathlessly extol the stunning realism of their particular products. Speaker manufacturers are often especially reckless, coming on about how their products reproduce exactly the sound that is on the tape (physically, of course, there is no sound on the tape, and there never was - only changing magnetic fields). So, accepting the premise of this hype as gospel, we often blame the differences that we hear on the equipment (as in, "This microphone sucks!" or "That console is just semipro junk!"). We've come to believe, from all this hype, designer audio stuff and tales from the studio, that we should be able to reasonably expect that the sound that comes out of the loudspeaker should be exactly the same as the sound that occurred in the studio. And so, we don't bother to ask a more basic question: is it possible to have the same sound come out of a loudspeaker that came out of the musical instrument?

The answer to this question is no, for a pair of reasons: first, the loudspeaker sounds different than the instrument it's mimicking, and second, the microphone doesn't hear the way our ears do!

Some other time, I'll talk about the loudspeaker problem (it's worth half-a-dozen articles, at least), but for now I want to concentrate on the input side of things in a very fundamental way: how we hear things as opposed to how microphones hear things. Once we begin to think in those terms, it gets a little easier to understand why sounds change when we record them, and what we can do to improve their realism and impact in a recording.
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COMMENTS

Staten Island, NY     Jun 10, 2006 11:36 PM
These articles are amazing, genius.... i can't wait to read all of them and then re-read all of them again... - Christopher
Christopher Sauter 
USA     Mar 12, 2010 03:46 AM
The article seems to miss that whether a mic/speaker or direct sound is emanating, the ear is going to be used and all its cool features and the brain processes inherent in that, unless we are talking about robots enjoying music. The comparison should instead be the sound that enters the ear in each instance. You would not want a mic to do the processing the ear does because the processing would be doubled with, no doubt, strange results.
Also, even though light moves faster than sound the brain take more, not less time to process vision. Watching the other musician instead of listening is probably not the best choice unless you can perceive the changes more clearly with vision than sound.
I also seriously doubt that we can tell what direction sound is coming from with one ear other than by moving our heads or already knowing how loud a sound should be if we were aimed at it optimally.
I have some hearing loss in one ear. If I put a hearing plug that ear, that mutes it by an additional 33DB, I am pretty close to deaf in that ear in that situation (which I have to do some times because the muscle he was talking about goes nuts sometimes). When that is the case I truly can't tell what direction sound is coming from with my good ear. My guess is that you are picking up some small bit of sound in the covered ear that is providing you with its direction. One ear direction I say is a total myth. Memory of a sound as it changes typically going around ones head may give cues we pick up, but if there is no relative movement history of the sound, I say I highly doubt any direction can be discerned.
mindbreaker 
Sydney, Australia     Dec 13, 2011 09:42 PM
mindbreaker is quite right; this article shows a complete misunderstanding of the way the acoustic recording/playback system works.

We would want the microphone to be similar to the ear if we were going to bypass the ear of the listener and insert electric signals directly into his nervous system, but this is, of course, not what we intend.

The role of the microphone is to capture information that is 'encoded' in air pressure fluctuations and convert it into a forma that can be stored. The loudspeaker is then called upon to convert this information back into its original form. Of course, there are many problems with this system, mostly at the loudspeaker end, but what matters at the microphone end is the completeness of the information-capture, not the exact mechanism.

Suppose, in an analogous case, that we take a page of handwriting, scan it into a computer, and then print it back into a new but almost identical page. It makes no difference that the scanner works in a totally different way from that in which the eye does, we just want it to capture as much information as possible.
Tim Smith 
Groton, MA     Dec 14, 2011 09:44 AM
Without spending a lot of time on this, there IS other research suggesting how single-ear localization happens. Further, I was startled by how robust I found that localization to be, even subject to its limitations. I'm not able to comment on mindbreaker's personal experience. My experience remains anecdotal, but easily, if fuzzily, repeatable. Thanks for writing, mindbreaker!
Dave Moulton 
Groton, MA     Dec 18, 2011 12:24 PM
Tim Smith makes some really good points in his post (although I disagree about my completely misunderstanding how acoustic recording/playback works – actually, I think I DO understand it).

Anyway, in this article I was comparing the ear to the microphone to illuminate various things about each of them, and also to show some places where we typically get confused. Tim isn't confused – he's got a really good handle on it.

The problems he doesn't get to have to do with where errors accrue in the capture of information at the microphone. We lose a lot there. Take a look at:

www.moultonlabs.com/weblog/more/we_want_really_accurate_recordings

Anyway, thanks, Tim, for an excellent and thoughtful post.

Best regards,

Dave
Dave Moulton 

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