I can explain where the DAWS frequently go “off-the-rails” with the compound (aka triplet) time signatures like 6/8, 9/8, 12/8. And the DAW mis-treatment of 12/8 as having two 8th notes = 1 beat (instead of 3), which leads people down a rabbit hole, wondering what the tempo is supposed to be, and what the heck is going on.

Imagine a 4/4 song, tempo of 60. Let’s say it’s a slow triplet feel blues. Now it has triplets throughout it, and someone prefers to call it 12/8. That is completely normal, and they could call it 12/8.
Now musically, we still call the 12/8 file as having tempo of 60. This is indicated as putting [dotted quarter note = 60] indicating that THREE 8th notes = 1 beat.
- the problem is that some DAWS look at 12/8, and think that TWO 8th notes = 1 beat. So they think the tempo of the file is 90, which would be needed to play the 12 notes (6 beats) in one bar. This would put the beats at non-musical points in the bar [beat 1, triplet 1] [ beat 1, triplet 3] [beat 2, triplet 2] etc.
- do now in the DAW we’ve lost the idea that this was ever a tempo = 60 song.

So the DAW is thinking that there are two 8th notes per beat, whereas COMPOUND time signature by definition have THREE 8th notes per beat. (12/8, 9/8, 6/8). If the DAW had a setting to declare that this is 12/8, but THREE 8th notes per beat, all would be well, and they would set the tempo to 60, which is the correct tempo, not 90.

Of course all this goes away if you just leave the time signature at 4/4 at tempo of 60, which BiaB does. And BiaB gives you the option to view as 12/8 notation, while preserving the 4/4 playback. As a bonus, you get to mix n match with the 90% of RealTracks and realdrums that are 4/4 based.

Attached Files (Click to download or enlarge) (Only available when you are logged in)
Have Fun!
Peter Gannon
PG Music Inc.