The command syntax for coding musical sequences is:
[phoneme<duration, pitch number>]
Each word or syllable is defined phonemically. The first number following a phoneme is the duration in milliseconds, and the second number is the pitch in Hertz. Vowels and consonants not assigned a pitch remain at the same pitch as preceding segments. You can intersperse silence phonemes if you wish. DECtalk stays exactly on pitch when the pitch is specified in Hertz (Hz). You can add vibrato (to give a more realistic singing quality) by specifying notes with pitch values from 1 to 37. Note 1 is C2 and 37 is C5 on an equal tempered scale (A4 = 440 Hz) as shown below. C2 is the second C below middle C on a piano, C4 is middle C, and so on.

An added feature of DECtalk is the ability to specify notes by their coded value equivalent (below). The coded value is simpler to write and is the exact equivalent of the pitch in Hertz.
When notes are specified, DECtalk reaches the desired pitch within about 100 ms after the start of the phoneme and adds vibrato after changing to this pitch. When you give a specific non-sung pitch, DECtalk reaches the pitch target at the very end of the phoneme with no vibrato. The following example makes DECtalk "sing" the first four notes of Beethoven's Fifth Symphony.
[d<100,17>aa<400> d<100,17>aa<400>]
[d<100,17>aa<400> d<120,13>aa<700>]