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mp3 in natural sound recording

Subject: mp3 in natural sound recording
From: "Rich Peet" <>
Date: Mon, 01 Aug 2005 17:03:18 -0000
In my comparing of various .mp3 settings I have not found a hiss
generated by the mp3 encoding.  I do find in some compressions hiss
that is more objectionable because there have been more "holes" blown
into existing hiss during the encode. For example, linked is a less
than 10% saturation mono file with the first half being the original
wave after being converted to 16bit, and the second half being the
same sound compressed into a mp3. Compression was 12.6 to 1 or 56kbps
at a 44.1 khz sample rate with a maximum bandpass of 12,002 cycles.
Encode by Fraunhofer IIS done within Adobe Audition. I leave it to
your ears if you find the high pitched hiss worse on the 2nd half of
this recording.

In mp3 compression of files I am not a fan of "variable bit rates" for
natural sound. All of these vbr methods, I conclude, make artifacts
worse in quiet recordings.

I would like a new "nature quiet" encode for .mp3. In this I would
like to see a complete 12,000 cutoff for highs, and 70 cycle for lows.
With various choices all in constant bit rate. Then I would also
prefer that the codex rather than have a pitch eliminated more pitches
are effected but at a 6 db level rather than an infinite cut level. 

2.5 meg download example at:
http://home.comcast.net/~richpeet/mp3.wav

Rich Peet


--- In  Klas Strandberg
<> wrote:
> Rob, can you make a "hiss" demo with different MP3 settings?? I am 
> unfamiliar with that sort of hiss. The noise I hear on John's
recordings 
> sounds like "typical transistor noise".
> 
> John - can we have a few seconds of the Robin or Coyote as .wav?? I
really 
> need to sort this out.
> 
> Klas.
> 
> At 03:24 2005-08-01, you wrote:
> >Thanks John! Love the yotes. Is the first single perhaps calling for
> >a  \partner thats out of range?  She/he is turning and calling in
> >different directions right?  The sources of three slap back echos
> >towards the end are interesting to think about too.
> >
> >I believe the widely distributed hiss, waivering and artifacts are
> >largely the result of the the mp3 encoding. Its 1:45 long  and
> >requires 1.6mb, so a data rate of 15.6K bytes/sec. Low even for mp3
> >standards. An uncompressed file would give us a better sense of
> >noise, if any, introduced byt the pre. Rob D.
> >
> >   = = =
> >
> >
> >At 2:55 AM +0200 8/1/05, Klas Strandberg wrote:
> > >Hi John!
> > >
> > >In his "self-noise" debate: Now when I hear your recordings again
- after
> > >getting acquainted with the NT1A, - I think I hear a hiss which
does not
> > >come from the mic.
> > >
> > >It could be atmospheric noise (leaves, grass in very minor wind)
but it
> > >sounds electronic. Is it the PMD670 or something else?
> > >
> > >Or is this what the NT1A sounds like when it is cold?
> > >Which temperature did you have?
> > >I hear it also on the Robin recording. Same "hiss".
> > >
> > >Klas.
> > >
> > >   when I listen to your recordings.At 01:08 2005-08-01, you wrote:
> > >>Last weekend I returned to the Aldrich Mountains: this time we
stayed
> > >>at Deer Creek Guard Station.  One nice thing about this forest
service
> > >>cabin (and also the one at Murderers Creek) is no electricity. The
> > >>lights, refrigerator, and stove run on propane, which does make some
> > >>noise but nothing like the annoying hums and buzzes that come from
> > >>electrical devices.
> > >>
> > >>Just after dark I went out on a walk listening for owl sounds, but I
> > >>didn't hear any.  A little later as the nearly full moon rose
from the
> > >>trees and illumined the meadow, a coyote began beckoning others to
> > >>join in chorus.  In this recording there are two coyotes, some
> > >>crickets, and a mystery bird - any takers? (1.6MB) (PMD670 full
gain,
> > >>NT1-As at 60deg and with barrier):
> > >>
> > >>http://www.rockscallop.org/ear/jh-050722-nightcoyote.mp3
> > >>
> > >>For Rob Danielson's comparisons of recorders and microphones, he
> > >>requested examples recorded at full gain. For the PMD-670, the
maximum
> > >>gain is an unimpressive 45dB.  Here's a 30 sec example at dawn
at full
> > >>gain.
> > >>
> > >>http://www.rockscallop.org/ear/jh-050723-0424_rl10-60dg-b1.mp3
> > >>
> > >>Here's another short example with the levels set at 7 out of 10.
> > >>
> > >>http://www.rockscallop.org/ear/jh-050723-0521_rl07-60dg-b1.mp3
> > >>
> > >>Here's another example (PMD670 set at 7) of coyotes joining in
chorus
> > >>around 5:30 am.
> > >>
> > >>http://www.rockscallop.org/ear/jh-050723-0526_coyotechorus.mp3
> > >>
> > >>Any comments, questions, or suggestions are welcomed.
> > >>-John Hartog
> > >>
> > >>
> > >>
> > >>
> > >>
> > >>
> > >>"Microphones are not ears,
> > >>Loudspeakers are not birds,
> > >>A listening room is not nature."
> > >>Klas Strandberg
> > >>Yahoo! Groups Links
> > >>
> > >>
> > >>
> > >>
> > >
> > >Telinga Microphones, Botarbo,
> > >S-748 96 Tobo, Sweden.
> > >Phone & fax int + 295 310 01
> > >email: 
> > >         
> > >
> > >
> > >
> > >"Microphones are not ears,
> > >Loudspeakers are not birds,
> > >A listening room is not nature."
> > >Klas Strandberg
> > >Yahoo! Groups Links
> > >
> > >
> > >
> > >
> >
> >
> >--
> >Rob Danielson
> >Film Department
> >University of Wisconsin-Milwaukee
> >
> >
> >"Microphones are not ears,
> >Loudspeakers are not birds,
> >A listening room is not nature."
> >Klas Strandberg
> >Yahoo! Groups Links
> >
> >
> >
> >
> 
> Telinga Microphones, Botarbo,
> S-748 96 Tobo, Sweden.
> Phone & fax int + 295 310 01
> email: 
>         





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