[Ardour-Users] more input sought on other MIDI sequencer behaviour

David Kastrup dak at gnu.org
Thu Jun 23 00:57:52 PDT 2011

Paul Davis <paul at linuxaudiosystems.com> writes:

> another similar question has arisen which i think can best be settled
> by comparison with existing sequencers. the question is: what happens
> when you split an existing region in the middle of a note. at present
> i can see 3 possibilities:
>    1) the earlier region sends a note off at its right (later)
> boundary, the later region never sends any note commands related to
> the split note
>    2) the earlier region sends a note off at its right (later)
> boundary, the later region sends a note on at its left (earlier)
> boundary
>    3) neither region sends any extra note on or note off commands
> there may be others.

I am aware that you asked for "how do others do it" and not "how do you
wish to have things done".

My personal take is that

a) cutting a region in two and pasting it back together should yield
identical results
b) pasting 4 bars of music one right after the other should yield the
same result as having them written consecutively
c) note-on requires note-off

Given all that, the behavior I want for editing usually is to split
regions according to their note-on events, and to have the note-off
events stay with their note-on events unmodified, even if it means that
they will happen _after_ the end of the region.

Which means that when joining regions "without overlap", note-off events
of the left region might have to get sorted _behind_ note-on events of
the right region.

In a somewhat similar problem space, the music typesetter Lilypond has
to deal with acciaccatura and appoggiatura, short upbeat phrases before
the beat time, but written _after_ the bar supposedly indicating the
beat time, and before the beat itself.  If you paste bars starting with
such phrases together with other material, those phrases have to be
extended into the time of the preceding material.

In a similar vein, when creating a drum loop, you can usually paste Midi
material end to end, but you can't paste the corresponding audio segment
end to end since the last notes of the loop sound out into the next bar
and can't be cut off.

So for a lot of manipulations, I would consider it an almost necessary
convenience to have the concept of having events/sound extending past
the nominal start/end of the region.

If you have that, you can just keep note-on/note-off together unmolested
when splitting regions, based on the time of the note-on event.  Being
able to manually sort even complete notes to the other side of a region
split (corresponding with an acciaccatura/appoggiatura) would be a boon.

But the principal point would be that the region start/end for the
purpose of aligning and splitting need not enclose all events/sound
associated with the region.

I don't know how other sequencers do it.  And frankly, I don't care.

David Kastrup

More information about the Ardour-Users mailing list