[Asterisk-Users] Re: Prompt recording

[Cees de Groot]

Jerimiah Cole  <asterisk-users at lists.digium.com> said:
>Does anybody have useful tips on creating good quality recordings for 
>use with prompts in asterisk?  I'm interested in hearing input on 
>hardware (mics, dats, sound cards, etc) and software (recording 
>software, dsp) as well as recording techniques.
>
For the dutch prompts we use a condensor mike (you know, the big things
they use in studios) and a Yamaha digital studio and 44.1kHz/16bit. I
like to get the original recording in as high a quality as possible,
leaves you more leeway before you get down to 8kHz/16bit. I get the
prompts as a single file with numbers spoken before each text - these
are quite handy as cue points, you can easily identify them visually in
audacity and it greatly speeds up cutting.

After cutting the prompts and saving them (audacity works nice for
that), this little script makes sure that all the voice prompts have
more-or-less the same (maximum) volume:

#!/bin/sh
tmpfile=/tmp/rescale$$.wav
for i in *.wav; do 
  scale=$(sox $i /tmp/foo.wav stat -v 2>&1)
  if [ $scale != "1.000" ]; then
    echo -n "Rescale $i..."
    cp $i $tmpfile
    sox $tmpfile -v $scale $i
    echo
  fi
done

Hth,

Cees
-- 
Cees de Groot               http://www.tric.nl     <cg at tric.nl>
tric, the new way           helpdesk/ticketing software, VoIP/CTI, 
                            web applications, custom development