Laura, I have listened to
http://soundcloud.com/laura-hilberg/6-12-12-bhm-nesp-11 and something
digital must be seriously and totally wrong with your set up or digital cha=
in.
No microphone or other analog unit sounds like that and certainly not
a Telinga connected to a PMD recorder. Even handling noise and noise
from the dish sounds just ridiculous. Every normal mp3 file sounds
MUCH better than that, so I can't hear that that would be the cause either.
I made a comment at 0,46 that I hear a limiter or automatic gain
control in action, and the same bumping can be heard at several
locations, but I don't think it is a limiter, but something worse.
If you can, please get the same set up working again with the same
settings and just talk into the microphone as if it was a common
interview. Best is if you remove the dish. Make a few minutes at
Soundcloud the same way as before.
Klas
At 01:07 2012-07-17, you wrote:
>Hi Laura,
>
>I downloaded both your files from SoundCloud. Listening to the
>longer file I would say that the quality is appalling and unuseable
>for any research purposes. I am surprised you were sent out to do
>field work without either having someone set the recorder correctly
>for you, or showing you what you needed to do. You should have been
>monitoring the sounds you were recording through headphones, then you
>would have known something was wrong right from the beginning.
>
>In analyzing what has gone wrong, I see that the audio frequency in
>both files only goes as high as 6.6 kHz, while the birdsong is
>starting at around 4 kHz and would have included sounds higher than
>6.6 kHz. Hence, apart from any overload problems, much of the
>birdsong is simply not in the recording.
>
>Such a low sample rate would be caused by using either a very low
>quality setting in the mp3 format and/or and sample rate of less than
>16 (should be 44.1 or more).
>
>When you are looking at a sonogram of properly recorded birdsong, you
>should be seeing a window that shows sounds up to 22 kHz.
>
>Vicki Powys
>Australia
>
>
>
>
>
>
>
>
>On 17/07/2012, at 7:18 AM, laura.hilberg wrote:
>
> > Thank you all so much for your suggestions (and experiments)! It's
> > a huge relief to have a community of people who really understand
> > this stuff.
> >
> > I uploaded a short recording of a single song (the same one in the
> > picture). It is on SoundCloud, and the URL is http://soundcloud.com/
> > laura-hilberg/nesp-song-short-clip. I made it public and
> > downloadable, so hopefully it will work for everyone. I also
> > uploaded the complete, unmodified sound file (about 10 minutes),
> > which is at http://soundcloud.com/laura-hilberg/6-12-12-bhm-nesp-11.
> >
> > To try to answer some of your questions:
> >
> > 1) I am absolutely sure that the automatic gain was turned off.
> > What this meant was that I adjusted it manually for each recording,
> > trying to ensure that the gain was high enough to pick up the sound
> > but not so high that it went over. I'm not sure if this is the same
> > thing as 'fixed gain', but I do know that it was adjusted manually
> > only.
> >
> > 2) The limiter was turned off.
> >
> > 3) Is clipping the same thing as aliasing (referred to in the Raven
> > manual)? If so, then I know what you're referring to, but if not
> > then I'm still not sure what exactly that is. John, your experiment
> > with the fan sounds exactly like what I am experiencing, with the
> > white shadow eclipsing the background noises in high-volume (or
> > perhaps it is related to high frequency) sounds.
> >
> > If it has to do with aliasing (as I understand it, sounds that are
> > over the Nyquist frequency are distorted upside down somehow), then
> > Raven has a low-pass (anti-aliasing) filter. I'll experiment with
> > that and see if it changes what I see. I know the low-pass filter
> > was turned off on the recorder, so perhaps this is the problem.
> >
> > 4) My files were recorded as MP3s, with a 44.1kHz sampling
> > frequency and 16-bit sampling rate. Perhaps this is the problem...
> > if so, then I am embarrassed to say that it's a problem I'm stuck
> > with, as that was the default file format, no one mentioned that it
> > wouldn't be good enough, and I didn't know enough to change it.
> >
> > Laura
> >
>
>
>
>------------------------------------
>
>"While a picture is worth a thousand words, a
>sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause.
>
>Yahoo! Groups Links
>
>
>
Telinga Microphones, Botarbo,
S-748 96 Tobo, Sweden.
Phone & fax int + 295 310 01
email:
website: www.telinga.com
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