One (hopefully) last question on Tempo Change subject.
I created 2 test files (4/4 time) that both contain 4 bars each, and each measure plays a whole note. Bar 1 has a metronome mark 1/4 = 60 bpm, and Bar 2 has a metronome mark 1/4 = 120 bpm
Test1a - all notes are un-tied - the created MIDI file has a duration of 10 seconds as expected (4s + 2s + 2s + 2s) Test1b - note in bar 1&2 tied - the created MIDI file has a duration of 12 seconds (I expected 10 seconds here also)
How would your sequencers handle these?
It is hard to properly convey my meaning in words only, so I sent you 2 png files to demonstrate.
You're quite correct, the file should remain with a duration of 10 seconds, whether with or without tied notes crossing a tempo change. It looks like the timing of the note that croses the tempo change is not being recalculated 'on the fly'.
Are you saying that my sequencer is handling this situation incorrectly (making a 12 second MIDI file), and your 3 sequencers each correctly produce 10 second MIDI files?
Yes, all of the sequencers I use correctly keep the duration at ten seconds regardless of tied notes. After all, it's not the notes that are the key, it's the length of each measure. One 4/4 measure at 60 bpm, three 4/4 measures at 120 bpm.
1st measure, 4 beats at 1 second per beat = 4 seconds. 3 measures at 2 beats per second = 6 seconds. Total = 10 seconds.
It makes no difference at all what is inside each measure. If a tempo change occurs, all notes need to be calculated/recalculated to fit. Especially tricky when, very often, played in sequences feature notes that are short or overlong compared to their notated values, and not exact divisions of a beat. That's musical interpretation, and MIDI sequencers (somehow) have to cope.
So for the long tied note, if the tempo remains unchanged, it would be held for eight seconds, but as it changes, the first half of the note is four seconds, but the second half is only two seconds long. Does that make sense?