[Wylug-help] wav file quality

[don]

Hi

I still haven't solved the problem. Setting the levels doesn't make any
difference. But I've tried a good .wav file and it sounds ok.

The audio starts off as an rmd file from the modem and it's converted to
wav format by the line below.

rmdtopvf -16 $MESSAGE | pvfspeed -s 7200 | pvftowav -16 >$WAVFILE


Don Magee


On Tue, 2003-09-02 at 12:09, Jim Jackson wrote:
>
> On 2 Sep 2003, don wrote:
>
> > I've just set up a linux telephone answering machine. But when I replay
> > the messages either with sox or xmms the quality is awful. I've tried
> > all of the different formats but none of them improve things. I think
> > that there may be issues with 8 bit samples from some of the comments on
> > the web.
> >
> > If I play the same wav file with windows software it sounds ok (well, as
> > good as 2 bit samples are going to).
> >
> > Anybody know how to solve this?
> >
>
> First off identify where the problem is. Have you played a known good
> wav file from another source?
>
> Is the quality any good?
>
> If not then, then there's a problem with the sound play back.
> Using a mixer controller have you shut off all unused inputs, have you
> played with the various volume controls to find the optimum low noise
> settings?
>
> If quality is good, then it's the recording side. Have you fully adjusted
> the mixer settings for optimum record level (NOT highest!  otherwise you
> overload the ADC and get distortion - the optimum level such that usual
> levels are recorded with a peak of about half the maximum possible so that
> slightly louder noises don'tr cause clipping and distortion.).
>
> Jim
>
>
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