Sox Wrap is an excellent OSX GUI for SoX. It makes batch operations on files very easy. I used to to transcode several sound files for my server tonight (Music on Hold and IVR prompts) and it was easier than any method I've used so far. The process we now use for creating high quality audio is:
1. Record prompts with a USB headset into Sound Studio for editing. Audacity would work fine too. Using a laptop that is not plugged in to AC eliminates ground loop hum.
2. Edit out pauses and noises, adjust volume, etc and save as a full quality wave file.
3. Use Sox Wrap to transcode – select the file(s) and let it auto-detect input. For output options choose: .wav, Sample rate: 8000, Signed Linear, 16 bit words, 1 channel. For music you may want to reduce the volume. Select the output path and hit the Run SoX button. This will product high quality native asterisk sounds. We may want to use gsm or uLaw instead of Signed Linear depending on the application.
4. Use Fugu to upload the files to the asterisk server.
For native music on hold you need to place the files in an accessible folder, and modify /etc/asterisk/musiconhold.conf
example:
Place files in new directory:
/var/lib/asterisk/moh-default
from an ssh terminal window:
nano /etc/asterisk/musiconhold.conf
Replace the contents of the file with this:
;
; Music on hold class definitions
; This is using the new 1.2 config file format, and will not work with 1.0
; based Asterisk systems
;
[default]
mode=files
directory=/var/lib/asterisk/moh-default
random=yes
Ctrl-X, Y to exit and save the file
asterisk -r
restart now (or restart gracefully to not interrupt calls)
asterisk -r
moh files show
You should see a list of your music files.