Cellphones and Audio (was Ghost Click, though I got no idea why)
jra at baylink.com
Thu May 3 01:11:24 UTC 2012
----- Original Message -----
> From: "Valdis Kletnieks" <Valdis.Kletnieks at vt.edu>
> On Wed, 02 May 2012 13:10:28 -0700, Jeroen van Aart said:
> > Technical specs aside I believe you are mistaken with regards to the
> > actual every day reality. My experience (and anyone else I talked to)
> > calling to and from mobile phones has been 100% a bad one with regards
> > to audio quality.
> I look at my Samsung cell phone, and the tiny speaker squeezed in up over the
> screen at one end, and then I think of the large speakers in the handset of an
> old-school Bell system rotary phone. Then I think about the fact that my
> laptop has pretty damned good sound quality when I plug in a good pair of
> Kenwood KPM-410 headphones, and sounds totally crappy over the tiny built-in
> speakers that Dell provided.
> It may not be the codec that sucks...
Me and my business partner have both spent quite a number of years involved
with sound reinforcement and other types of audio engineering, and we're
therefore better positioned to evaluate the transmit and receive audio of
various communications channels and physical interfaces there to.
It is *often* the analog components and housing that make things sound
suboptimal, and if you need proof of this, I call to your attention some
NPR phoners which are done with gear like the JK Audio BlueDriver 3, and
broadcast microphones. It's possible to get to within about 47% or so of
the sampling rate of the codec using gear like that, and it's pretty easy
(for a sound guy) to spot that combination in a live broadcast.
It's also worth noting that even if the recording format is VHS, it's very
easy to discern the difference between consumer cameras, pro SDTV, and pro
HDTV, in looking at the playback signal -- the differences are subtle, but
they are identifiable.
Now, those codecs *are* specially tuned for spoken word -- if you try
to stuff music down them, it's not gonna work very well at all...
Jay R. Ashworth Baylink jra at baylink.com
Designer The Things I Think RFC 2100
Ashworth & Associates http://baylink.pitas.com 2000 Land Rover DII
St Petersburg FL USA http://photo.imageinc.us +1 727 647 1274
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