Re: Tuplet Ratios

[Keith OHara]

carltesta <ctesta <at> wesleyan.edu> writes:

> I am working on typesetting another composer's music. In their music they
> prefer to notate a 5:4 tuplet (5 sixteenth notes in the space of 4 sixteenth
> notes) as 5:1 (5 sixteenths in the space of 1 pulse (quarter note). Is it
> possible change Lilypond's MIDI encoding so that if I write the tuplet as
> 5:1 that it will play it back as a 5:4? Instead of 5 sixteenth notes in the
> space of 1 sixteenth note?
> 

Do not expect that you will need to adjust the MIDI.  LilyPond uses the same
counting of time for spacing and for MIDI, so when the placement of notes
relative to bar lines and other voices is correct, so will be the MIDI.

Maybe best to enter the music under usual conventions, and replace the printed
notation
  \once\override TupletNumber #'text = "5:1 (Wesleyan notation)"
  \times 4/5 { a16 b a g a }

You can tell LilyPond to print sixteenth notes that actually lasts four times 
as long, as if they were quarters (but it would not help you to have LilyPond 
do the math if you need to do math yourself to figure out what to input).
Details in Notation Reference 1.2.1

\relative c'' <<
 \override TupletNumber #'text = #tuplet-number::calc-fraction-text
 { g' \times 1/5 {a b a g a} b4 \times 1/5 {a16*4 g a b a} } \\ 
 {b,4 b b b} >>