A Ring Back Tone (RBT), or
Audible Ringing Tone or Ring Back Signal, is
the audible ringing that is heard on the telephone line by
the calling party after dialing and prior to the call being
answered at the receiving end.
Companies that refer to call tones as
ring back tones are only creating confusion amongst those
people who are looking for call tones for their phones.
Ring Back Tone
Characteristics
The ring back tone is different in
various countries depending on the requirements for the
ring back specification in those countries.
For example, in the NANP (United
States, Canada, and others), the standard ring back signal
is generated by summing a 440Hz tone with a 480Hz tone and
applying these to the telephone line in a 2 second on and 4
second off cadence. The tone combination produces a
warbling "ring... ring..." sound, caused by the 40Hz beat
between the two.
Most other countries use a single
tone, as do some PBX and key phone systems.
In the UK and many other Commonwealth countries, it's a
signature double beep, which has been made famous by being
included at the end of Pink Floyd's "Another Brick in the
Wall, Part 2."
The ring back signal may be generated
by the called party servicing switch or by the calling
party switch, but it is not generated by the called
telephone instrument. It is generally started and stopped
at the same rate as the ringing signal itself but perhaps
out of phase.
- Unfortunately, ringback tone is still used
to describe the ring-ring sound that people will hear
on your phone when you don't have any call
tones.
Remember:
When you are searching
the Internet for call tones, not all suppliers actually
refer to them as call tones. Some of the other terms you'll
have to search for are...
Using the above search terms, you
should find the call tones you're looking for, especially
if the call tones suppliers are using one of these
alternative descriptions.
Good Luck in your search.
Call tones are actually more
versatile than ringtones.
