Very, very nice, Dan. I couldn't put it any better myself...
Martyn
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Martyn Stewart
Bird and Animal Sounds Digitally Recorded at:
http://www.naturesound.org
Redmond. Washington. USA
N47.65543 W121.98428
e-mail:
Tel: 425-898-0462
Make every Garden a wildlife Habitat!
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From:
On Behalf Of Dan Dugan
Sent: Saturday, May 26, 2007 11:29 AM
To:
Subject: Re: [Nature Recordists] 16 bit vs 24 bit Information Theory
Hypothesis
Importance: High
George Paul, you asked,
>If we have more information, then why aren't we creating a
>representation of reality that is superior?
Good question, deserves a thoughtful answer. It's a matter of where
you draw the line between "good enough" and "overkill," and that's a
personal, artistic, and economic decision.
It's going to be very difficult to tell the difference between an
excellent 16/44 recording and a corresponding 24/96 recording, for
example. But there's a general principle in media production that the
master should be of the highest quality possible, so that it has a
quality edge that will help it survive the necessary processing to
produce a useful end-product. And "legs" for future distribution
media that might have higher quality.
24-bit recordings take up 1.5 times the file space of 16-bit
recordings. 96K recordings take up 2.18 times the file space of 44.1K
recordings. So the 24/96 recording will use 1.5 x 2.18 =3D 3.27 times
the file space of a 16/44 recording. The rule of thumb for 16/44
stereo is about 10MB/minute. 24/96 recording will use 33MB/minute.
Storage is becoming cheaper by the day, so that consideration isn't
as important as it was when digital was young.
Since converters top out at around 21 bits, 24-bit seems to have
sufficient overkill. Gives us some wiggle room for conservative
levels. I don't see that changing in the near future.
Stockham, inventor of digital audio recording, found that 50K was the
optimum sample rate--anything more would be overkill. So 96K is
already probably wasting a lot of space on no useful information, and
the only reason to go higher would be to extend bandwidth into the
supersonic, useful only in science work.
If I had an unlimited budget I'd record 24/96. But I don't, and like
Walt and others, I manage (most of the time) to make recordings that
are both scientifically useful and aesthetically pleasing with MD
(ATRAC encoded) recording that is 16/44 with a low-pass at about
Message: 16KHz.
Subject:
-Dan Dugan
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