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Re: [ARSCLIST] A fundamental Flaw: Was Sampling Theory (was Fred Layn's post on the Studer list re: Quantegy)



see end...
----- Original Message -----
From: "James Lindner" <jim@xxxxxxxxxxxxxxxxx>
> A couple of months ago I was at a series of live concerts and I started
> wondering if there has been a fundamental flaw in the way we capture
sound -
> either analog or digital. When I say fundamental I mean fundamental. I am
> inspired by the comment a few emails ago about the sound of a live band or
> double-reed. Like all of you I have spent many years with sound - both as
a
> professional and as an individual - and I have to say - that looking from
> 50,000 feet - that it feels to me that there are fundamental errors in the
> way we record and reproduce sound. I too have heard many, many different
> speakers and microphones - but really do any of them really reproduce
> ACCURATELY what we are hearing? I really don't think so. Why? I am not
sure
> - but I have some ideas, or really some questions - and I am not sure that
> the fundamental questions have really been asked in a VERY long time.
>
> For instance - is it only about sound pressure? Is it only about frequency
> response? Is it only about phase cancellation? If so - lets be honest - we
> should have had it licked a LONG time ago. But we haven't. We are not
> capturing presence - or at least much of it. Multi channel systems come
> closer - but still there are fundamental issues. I was thinking about a
> system that used a net of microphones in an area and a signaling system in
> the network that somehow took into account temporal delay at different
> frequencies reaching different "microphones" (I think they would be
> fundamentally different then any mic. made today)at different times. The
> reproduction system would have to be similarly different. I envision
> actually 2 different types of signals being captured. The audio pressure
> information that we now capture - but also the temporal delay and bounce
> across the spectrum - information that we don't capture at all other then
> capturing the RESULT as sound pressure, after it is all mooshed together -
> when it is too late. The reproduction would be changed based on the
> information contained in the temporal data stream. There would need to be
a
> similar net of speakers for reproduction. I am not sure that this is it
> entirely either - because no acoustic environment is identical - so you
> would have to take into account the acoustic environment on capture as
well
> as reproduction. Reproduce the result in 3-d space of the acoustic objects
> in the original space. Kind of like an acoustic virtual reality
recreation.
>
> It occurs to me that sharing these musings in a public list may not be the
> best place - perhaps over a beer or two would be better in a more private
> forum, these ideas may seem like craziness to some of you. Perhaps I am on
> the wrong road entirely - nevertheless I have to ask myself and ask all of
> you - an exceptional collection of knowledgeable people - the fundamental
> question - have we somewhere made a BIG mistake and missed something?
>
> I totally agree with many of the comments - while we can debate Analog and
> Digital issues - they are relatively subtle as compared to the BIG issue
> which is - why does sound recording (analog or digital) sound so bad as
> compared to the live performance? This is not subtle - it is obvious. It
> just isn't close. For me ribbon speakers come the closest in terms of
> reproducing that sense - but they fail too. What have we missed? Where did
> we go wrong? It seems to me that all our engineering went in one direction
> and no one ever looked back. Well I am looking back - and wondering. Where
> did we go wrong? If the goal was really to reproduce the sound of live
> performance - then clearly we have not succeeded. Something is clearly
> missing. What?? And how do we fix it?

My answer...yes, there is a faw...or, more accurately, a mixture of flaws!
As well, there have been a series of flaws as sound recording evolved.

Consider that our brains obtain data from our ears...not only by the
actual sounds heard but also all the data that can be deduced from
those sounds. Back in our hunter-gatherer days, this data was essential
to our survival...so we became adept at obtaining it, and in fact doing
so without conscious thought about the process!

We had to know WHAT made that noise...and WHERE it was! If we heard a
twig snap, we not only had to know what we had heard...we had to know
where it had happened. It was that information, and our success at
obtaining it, that determind whether we ate the bear...or the bear
ate us! Needless to say, folks that lacked this important skill
didn't get to reproduce.

Now, this gave us TWO important skills. First, we became able to
locate sound sources (more later). Second, we became adept at
identifying extraneous sounds...sounds we didn't want to listen to...
and it identifying and listening to the sounds we wanted to. I can
remember being able to pick out a single cw signal from a group of
them, and following it...or picking up a single station from the
chaos at 1240 kHz long enough to hear a station id itself! We can
also carry on conversations in crowded rooms or on busy city
streets...or, go to a crowded bar and listen to a band. We edit
out the "garbage" mentally, and hear (and remember) what matters
to us!

The first point above means that we need two different kinds of
aural information to satify our brains. We need the binaural data
supplied by our two ears (which "stereo" finally allowed us to
hear, more or less) and we also need the subtle information
supplied by echos and reverberation. For a good example of
this, listen to Waring's Pennsylvanians' record of "Freshie!"
Most Victor records were recorded in "dead" studios...padded
to remove all echo and reverberation. For whatever reason,
this one wasn't...and my first thought on playing it was
"This must be in stereo!" The information the reverberated data
gave my mind was that important to it.

The problem is that modern recording is just as useless in giving
our ears and minds this data as Victor's padded roomes were
decades ago! We record with any number of mikes in a variety of
positions...and then mix all of these signals together into one
"moshed" mess carrying no useful data. Even worse, we may add
artificial reverberation, which probably creates contradictory
data! When we hear the result, we have no idea "where the bear is!"

Finally, our minds are probably less efficient at editing out
recorded rxtraneous information (aka "noise") than that of a
live setting. I've always thought if someone took a pair of
microphones into a club where a band was playing and positioned
them to pick up and record what I actually had heard, I would
be shocked and appalled at how little of the music was clearly
audible! That wasn't what I remembered hearing!

Steven C. Barr


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