Understanding MIDI export results

[rotacak]

Hello,

I want to ask why when in MPT is for example D6 note but after export to MIDI is there "D5"?

I can see it there: http://tonejs.github.io/MidiConvert/

Can it be somewhat synchronized?

[Saga Musix]

OpenMPT uses a notation that is different from common MIDI note names. This is because OpenMPT is not a MIDI software and has its roots in Impulse Tracker, which has a note range from C-0 to B-9. If we were going to use MIDI note names, C-0 would suddenly be C--1, i.e. the octave would be negative.