Several of the almost-final MIDI files from the soundtrack I am currently converting (SNES to MIDI) seem to be okay, yet there are a few specific notes that do not seem to play any sound, and I'm having trouble determining why this is actually happening.
Firstly, I have isolated the channels/tracks in question and made audio recordings of the original vs the MIDI output. You can see that one channel of the stereo audio in the MIDI file (top half of the screen) is silent while it should be playing a sound, when compared with the original audio (bottom half), which is fairly similar across both stereo channels.
I've tried looking at the event lists for both tracks/(MIDI) channels in Sekaiju, but don't see anything that jumps out at me. I looked at the channel volumes and expression lines in MidiEditor, and also don't see anything that is obvious, though it's hard to determine what is what sometimes because of display issues with the GUI. Tracks 3 and 4 play the same notes, with one track delayed slightly, so the expression and volume lines are shifted between the two, but identical. I don't see anything in particular in Cakewalk either.
This issue happens because of limitations of the spc2mid converter, and can be heard while preparing the initial MIDI file for export, so my guess is there is an incorrect value being set for either expression, volume, or pan, but I can't determine which or where specifically it's happening.
I'm unclear what point in your MIDI file you are having the problem. But here is a suggestion:
In Cakewalk, try going to the Piano Roll window and looking in the controller graph at the bottom. This should make it easier to see the controller values and help you figure out the cause.
[quotePost id=15833]I'm unclear what point in your MIDI file you are having the problem. But here is a suggestion:
In Cakewalk, try going to the Piano Roll window and looking in the controller graph at the bottom. This should make it easier to see the controller values and help you figure out the cause.
[/quotePost]
Oh, yeah, sorry, I meant to put that it's at about the 10 second mark (10:20 is where the audio screenshot begins).
I fiddled around with the values in the piano roll view in Cakewalk. It looks like it might be the values of CC7 causing this particular issue. I tried leveling it out over the course of those notes and it seemed to get better. I think the heavy use of expression combined with the lower volume values for some of the notes is making some things too quiet, where they are essentially off. This entire game soundtrack I had to boost the volume by 45 in the converter for every instrument, or I was losing whole entire instruments in certain songs.
Hopefully I will also be able to track down a few pitch issues this way as well. I have some very sour "strings" in a few of the songs.
[quotePost id=15835]I fiddled around with the values in the piano roll view in Cakewalk. It looks like it might be the values of CC7 causing this particular issue. [/quotePost]
Yes, that did the trick. I loaded it in Sekaiju, and noticed that everywhere there were issues, the Volume was set to 45, while the surrounding notes were set to 73, so I changed all of the 45's to 73's and now it sounds significantly better.
EDIT: I went back and used Notepad++ with the Hex Editor plugin to search and replace 07 2d with 07 3c (raise volume from 45 to 60 instead of 73 to still maintain some variation just in case) in all of the songs. It seems to be better all around for the most part. I don't think anything else non-volume related would get affected (hopefully). test-midi-files shows no issues with any of the files.
Ahh, well, it was a noble effort. I'll have to rethink how to replace the volumes. One of the files has 07 2d in places other than a volume change, so the tracks are getting misaligned and causing audio issues. I'm also not sure if I like how the evening out of the lower volume levels affected some of the files, effectively squashing some of the already squashed dynamic range from having to boost everything so much in the converter.
Final analysis:
The issue only effects certain sections of certain files. The converter is setting a low volume plus a lower expression value, which is combining to make it too quiet. I used Sekaiju to manually edit the offending volumes and raise them from 45 to 73 to match the volume of the same instrument that is playing on another channel at the same time. This makes the volumes closely match the levels from the original game files.
I probably have to do something similar with the pitch on a few of the songs, as little bits here and there are slightly out of tune, but not enough to warrant an entire note shift. The files make heavy use of pitch shifting, so some number somewhere is probably a little higher or lower than it should be (guessing a Fine Pitch value).