BenQ Z2 - Manual (Page 113)

Menus 97
Composer
You can edit your own polyphonic ring tone melodies, and use
them as alert sounds for incoming calls.
A polyphonic ring tone consists of musical tones in multiple
channels. The Composer function allows you to create a maximum
of 8 channels, mixing them to create the final polyphonic ring tone.
Note format
Entering default notes
Press to to enter the seven pitches in the middle
octave as quarter notes: Do Re Mi Fa So La Ti. The screen will
display: 4C5, 4D5, 4E5, 4F5, 4G5, 4A5 and 4B5.
Entering a default rest
Press to enter a quarter rest: 40.
The "4" on the left shows that the represented note is a
quarter note; the "5" indicates that it is in the middle octave.
Length Octave
Sharp Pitch