how to send raw MIDI?

[Johannes Waldmann]

Hi.

Is there a way to send raw MIDI messages
(that is, sequences of bytes) from a description
inside a lilypond text? (possibly embedded LISP)

my application: to an external synthesizer device
that accepts a lot of control messages.

Base case: I want to send "program changes" where the argument
is an actual number, and not a general MIDI instrument name.
Then, there are a lot more messages like
(hex) [ B<chan> , 4A , <val> ] for "filter cutoff"

yes I understand it's probably not the right thing to do
(e.g., how should these messages appear in the printed score?)
but I think it'd be convenient.

Thanks - J.