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RE: P3D information



> > The overall sound quality of most digital cellular systems 
> is far worse than
> > the analog ones.  People sound like they are talking out of 
> a fishbowl!
> 
> Interesting observation. GSM with EFR (enhanced full rate) sounds
> quite good IMHO, and GSM without EFR sounds quite reasonable.

I second your comments.  GSM audio quality has never been an issue with me.
In the early days, there were problems with dropouts and garbled audio as
the networks were still being built, and no doubt some early handsets didn't
perform as well as the current crop.  But when it was working, I had no
complaints about the audio.

Nowadays, GSM is very good.  I can't comment on CDMA audio directly, though
I have spoken to a couple of people who have CDMA phones, and have no
complaints about audio quality on those calls (even when calling from GSM to
CDMA).  As for analog, when signals were strong, audio quality was
excellent, but in the areas I travelled, I often had problems with mobile
flutter and crosstalk between cells, the latter degrading intelligibility
severely.

One of the final checks I have on audio quality is replaying audio via a
larger set of speakers, such as a stereo system (even a good portable is
good enough).  GSM audio is readily available, courtesy of your local
talkback station, and generally comes across well in this environment.  CDMA
is a bit more difficult to tell, unless one knows the number being called.

Analog is (understandably) on a par with VHF/UHF FM, with very good audio
quality.  Bottom of the heap is good old SSB, where the background noise is
apparent in many cases, there may be a frequency error (depending on how
good one is with the RIT! :) ), and on some paths (aurora, long haul HF, low
band), there are various subtle distortions that degrade the audio
further...
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