On 2026-02-24 22:36, metachromatic wrote:
"We don't require this level of detail in music expressions for dynamic
ramps."
You don't -- many other composers do.
I want to correct some misinformation in Metachromatic's message for the
sake of bystanders who might otherwise be thrown off track.
Arnold proposed this scenario:
you specify the total duration (e.g. 4 measures),
the frequency (e.g. each quarter an update)
and the relative final tempo (e.g. 2/3)
This describes a ramp in tempo. LilyPond MIDI output already supports
ramps in dynamics (i.e., decrescendo and crescendo) without users having
to do the math and insert absolute levels periodically in the music
expression. At the moment, I don't see anything that would stand in the
way of doing something similar for tempo changes. To a person
interested in trying that, I'd also encourage thinking about slowing the
MIDI tempo by a parameterized amount for a parameterized time at \caesura.
inability to specify tempo changes as real numbers (from tempo
73.241 to tempo 74.856, for example)
Rational numbers are sufficient for these examples, and LilyPond
supports rational numbers.
https://lilypond.org/doc/v2.25/Documentation/notation/displaying-rhythms#metronome-marks
The MIDI output uses an approximation constrained by the MIDI design.
The default metronome mark rounds to an integer, which is reasonable for
music of the era that LilyPond's defaults usually target. As for many
other things, the user can override the stencil or add text to describe
a tempo change in any way that can be put into writing.
--
Dan
