I made this set of telephone tones for an IP-PBX running asterisk. A lot of telephone-related audio files on the Internet seem to be recordings of actual beeps, so the quality is not great. Given that they are trivial to synthesise with Audacity, I made these:
- Dial tone
- Busy tone (or single tone to loop)
- Call waiting tone (or single tone to loop)
- Ringing tone (or single tone to loop)
To convert them to .ulaw format for asterisk (click here to download archive), I saved them as a .wav file and ran this bash script over the directory:
#!/bin/bash
for a in *.wav; do
sox $a -r 8000 -t ul $a.ulaw
done
Making tones for other countries
Get a copy of the document "Various tones used in national networks (According to ITU-T Recommendation E.180) (03/1998)". It describes the tones used in most of the world. There is also a Cisco tones database, which has slightly different numbers.
Open up Audacity and use the Generate → Tones feature to make the first beep. Where there are multiple frequencies, make each frequency in different tracks, then merge them into a single track.
Use Generate → Silence to add the delay on the end, then continue from there
Afterward, you need to normalise the volume. Read the number from the volume Cisco tones database, then use Effect → Amplify, and set the new peak volume to the value shown — for the above tones this is -10 or -13dB.