Telephones--what are the notes???

Subject: Telephones--what are the notes???
From: Vixen
Date: 13 Sep 01 - 08:10 AM

'D'Cats:

I'ven't posted in awhile, but I've got a musical question I can't figure out by trial and error...

What are the notes of the numbers on a touchtone phone???

Are they standardized, so that no matter what the note is, the intervals between the numbers are consistent???

If so, what are the intervals?

I know when touch-tone first came out, there were number sequences that played happy birthday and the like...is that still true???

Those of you who know me, know that I don't hear very well, and my telephone hearing is abominable--I can barely hear the tones when I dial. In fact, most of them are beyond my hearing range in my best ear, so any help you can offer would be gratefully appreciated.

Meowchas gracias,

V

Subject: RE: Telephones--what are the notes???
From: MudGuard
Date: 13 Sep 01 - 08:29 AM

for DTMF (Dual Tone Multiple Frequency) each key is sent as a combination of two frequencies - these are standardized internationally. The frequencies and keys are listed in the table below, for each key the combination of the frequence at the top and at the left is sent. Example: for 9, frequencies 1477 and 852 are sent simultanously.

Frequencies	1209	1336	1477	1633
697	1	2	3	A
770	4	5	6	B
852	7	8	9	C
941	*	0	#	D

HTH

MudGuard

Subject: RE: Telephones--what are the notes???
From: MudGuard
Date: 13 Sep 01 - 08:31 AM

Forgot to write: most phones do not have the A, B, C and D key.

Subject: RE: Telephones--what are the notes???
From: Vixen
Date: 13 Sep 01 - 08:38 AM

Dear MudGuard--

Thank you thank you!!!!

I just *knew* there would be a mudcat (or more) who would have the answer!!!!

Thanks Again!

V

Subject: RE: Telephones--what are the notes???
From: Armen Tanzerian
Date: 13 Sep 01 - 10:29 AM

Well, if I'm reading this right, the letter keys do not correspond to the musical notes A,B,C,D, but are merely an extra row of buttons found on special phones. In fact the touch-tones are not pure notes of any key, but a few of them offer a rough approximation by which one can play little off-key tunes. My dial tone, however, is real close to a pure F.

Subject: RE: Telephones--what are the notes???
From:
Date: 13 Sep 01 - 10:46 AM

Armen, that's correct. They are TWO frequencies generated each time you press the button. Also ABCD are NOT the letters of the keypad. There are some specialized phones (we WON'T get into that) which have those buttons to do things the phone company does internally.

 

About 20 years ago, someone published two or three books of tunes playable on the telephone keypad. I used to have volume 2, but lost it somewhere in life.

See if your local library might still have such a book or two around.

Subject: RE: Telephones--what are the notes???
From: Charcloth
Date: 13 Sep 01 - 04:14 PM

Jingle bells is-----8-8-8--8-8-8---8-0-2-5-8

Subject: RE: Telephones--what are the notes???
From: GUEST
Date: 13 Sep 01 - 05:03 PM

Try clicking here

Subject: RE: Telephones--what are the notes???
From: Vixen
Date: 14 Sep 01 - 11:10 AM

'D'Cats--

This has been very helpful. After some more research, both in Physics texts and on the websites provided here, followed by some experimentation with my phone, a tape recorder, Tim, Tim's guitar, and my electronic keyboard, I have another question...(you just knew it! there's no END to the questions!)

Since the frequency combinations are not equal to any two notes of the Western scale (not in natural intonation, equal-temperament, or pythagoran intonation--can you tell I've been doing some research since yesterday???) I'm now trying to figure out how to tune a stringed instrument to those frequencies. What I THINK I need now is a tuner-type device that shows the frequency of the sound and not its "note-value pitch" (A, B, C, ... G). Does such a device exist? Also, am I correct to assume I'm risking snapping something essential on the instrument if I try tuning it's strings up to 1633Hz? I figure it had better be a treble-pitch instrument to start with, and I had better use the lightest of strings. Does this make sense? Or should I consider tuning the strings to one-half of the listed frequencies and playing at the midpoint of the neck to get the octave frequency??? Would a SYNTHESIZER do what I want--electronically producing tunable frequencies???

Any IDEAS??? Maybe I need to take an acoustic physics class, but I don't think that will help with the instrument questions...

More thanks; Mudcats are the best!

V

Subject: RE: Telephones--what are the notes???
From: Cappuccino
Date: 14 Sep 01 - 05:11 PM

That website of touch-tone tunes is fun. Can we set up a session, please? - IanB

Subject: RE: Telephones--what are the notes???
From: Armen Tanzerian
Date: 14 Sep 01 - 05:21 PM

I believe the sheer economic clout of the American market dictated that all of the answering machines being pumped out of the Far East respond to the American touch tones, which in turn caused most of Europe and the UK, where those same machines are sold, to integrate them into their systems as well. But BEFORE these tones became ubiquitous, one could buy a little hand-held tone generator. They were sold to those of us who frequently travelled in Europe or elsewhere so we could "talk" to our answering machines back in the States from the old toneless phones - you simply held the little thing up to the phone and beeped away. You might be able to find one hiding in a Radio Shack or some similar place. I assume you want to create a contemporary composition using these now universal sounds. Unless....hey, you're under arrest!

Subject: RE: Telephones--what are the notes???
From: Sorcha
Date: 14 Sep 01 - 05:21 PM

There are tuners that use a frequency needle instead of sharp/flat/ lights........one of those might work.

Subject: RE: Telephones--what are the notes???
From: Bill D
Date: 14 Sep 01 - 06:11 PM

my Korg can be set to any value of 'A' between 438 & 446...and the values of the other notes can be gotten and re-calculated, even though the readout is for notes of the scale.

Subject: RE: Telephones--what are the notes???
From: Vixen
Date: 17 Sep 01 - 10:01 AM

'D'Cats--

Thanks again for the helpful info--a tone generator sounds like just the ticket for at least working out my ideas. Armen, no, I'm not contemplating defrauding the telecommunications companies; yes, I've dreamt up "a contemporary composition using these now universal sounds." In fact, what I'm hearing in my head is a whole symphony, but I haven't a clue about how to get all the intruments tuned correctly. Especially the woodwinds and brass...That's why I asked about the intervals being consistent with western scales...if the intervals are consistent, it's just a matter of transposing out of the "touch-tone" key into a western key. However, what I've read about the subject tells me the intervals are *close* to the intervals of western scales, but not "identical" (bearing in mind that the scales AND their intervals are an artificial and mathematical attempt to impose a consistent order on the chaos of natural sound!) Also, my reading indicates that these frequencies were chosen to eliminate any harmonic resonances, and presumably, overtones, in order to make them unambiguously decodable.

Whew--

All advice and suggestions are gratefully appreciated!

V

Subject: RE: Telephones--what are the notes???
From: Rich(bodhránai gan ciall)
Date: 17 Sep 01 - 10:33 PM

A friend and former bandmate of mine, told me that while living in NYC he and other discovered that the dialtone on the payphone where they played for céilis was a perfect "A"
I don't know if that's standard or a fluke.

Rich

Subject: RE: Telephones--what are the notes???
From: MudGuard
Date: 18 Sep 01 - 02:45 AM

AFAIK the dialtone is not standardized the way the dialing frequencies are, so the dialtone might vary from place to place.

Subject: RE: Telephones--what are the notes???
From: open mike
Date: 18 Sep 01 - 02:02 PM

interesting--i was seeing a topic similar to this on a radio chat list--and it came up that most dial tones are A=440. the radio station crew was talking about broadcasting that tone, like they used to b-cast dolby calibration tones..