[Asterisk-Users] Re: IVR GSM voice prompt quality

[Chris Maresca]

On Tue, 27 Apr 2004, James H. Cloos Jr. wrote:

> >>>>> "Steven" == Steven Critchfield <critch at basesys.com> writes:
> 
> Steven> Conversion should be nothing more than sox orig.wav orig.gsm
> 
> Are you sure they come as signed linear 8 kHz wav files?
> 
> The uncompressed files John has on his site are 44.1 kHz PCM
> aiff files, so something more like this is required for optimal
> sound quality *if* that is how Allison records the files:
> 
> sox file.aiff -c 1 -r 8000 file.gsm resample -ql

That's what I have right now, but I think that between the GSM
compression, the D/A conversion in the X100p and cell phone compression, I
am getting really crappy quality.  

Steven's suggestion was, I think, uncompressed GSM, which I may try
(although I don't know what alogorythm/quality * supports...).

What I am wondering is wether I can use different compression +
equalization to get better sound or is this just a lost cause with PSTN
analog lines?

Thx.

Chris.
 
> -JimC
> -- 
> James H. Cloos, Jr. <cloos at jhcloos.com> <http://jhcloos.com>
> 

--
chris maresca
      senior partner - www.olliancegroup.com

linux, up 22 days