International call progress tones for IP-PBX and VoIP telephony

Telephone Line Signalling

Test tone

  • Also known as the Permanent signal tone and the Test tone.
  • A tone played out to a line after an extended period of off-hook state where the line is not involved in a call.

Search for Test tones in the World Tone Database
Back to guide
Related product: CPT-Master tone generator app