Hi Bruno!
First, I would like to thank you for your work with these apps (MidiKit, Qmidi). I'd like to request a feature to you. Do you think it's possible to add a function in MidiKit that allows me to swap midi channels - let me explain why - when you have a midi file with all 16 channels used it's not possible to change let's say midi channel 1 where the melody is to put it in midi channel 4 (without merging or deleting the information on this channel). When you have empty channels it is easy. This is important because sometimes you need to correct a midi file that has melody in a channel that you want in another (the standard midi channel 4 convention to use melodies - in my case I use Roland BK-9 and it is easy to mute or unmute this channel in all my midi files when I want). With a swap function (change midi channel 1 to 4 and put midi channel 4 to 1 without deleting or merging the information on those channels) would make this process very easy to do. I hope you can do it. Thanks for your attention, João Luiz.
You're right, if you have an empty channel you can swap using the empty channel as temporary buffer... Not the case when all channels are used. Thanks for the suggestion :)
Be aware that swapping MIDI channels may have unexpected consequences in the BK-9 (and many other keyboards) if they have any sys-ex in them. And sys-ex is used a LOT for Makeup Tools work... particularly effects, MFX and drum Part edits, but also many other parameter offsets.
Sys-ex has embedded code that is specific to the MIDI channel (TBH, sys-ex isn't really channel information at all) so moving all data from one channel to another won't affect this. I recommend doing a 'Freeze Parameters' in the Makeup Tools prior to doing a channel swap, so whatever changes made there (and stored as sys-ex) that can be converted ARE converted into normal channel codes before swapping.
This won't fix everything, but it can help with some things...
In my case I think this swap function helps a lot. In many cases where all the 16 channels are used and for example the melody is in the channel 1 and I need to change it and put in the channel 4 where in the Bk-9 it's muted by default.
I have certain midi files that I've bought in the past that have the melody in channel 1 or 16 for example. In that time I used a laptop with Cakewalk Sonar and muted the corresponding channel. Now that I have the BK-9 it is more practical to change these files and make the melody on them move to channel 4.
As long as you haven't already done a bunch of Makeup Tools to the parts, and they are standard GS/GM SMF's. channel swap should work fine. But if you do hear something odd, Makeup Tools' sysex is most likely the culprit.
And, although the BK's default Channel Mute is CH.4, it CAN be changed in the Globals. So if you have the vast majority of your SMF's with it on Ch.16, it might be quicker to change the default Mute rather than channel swap most of your SMF's...
BTW, I moderate the Roland-Arranger.com forum, so if you have any other Roland arranger questions, feel free to join and contribute to our discussions there (hope you don't mind a mild plug for our forum, Bruno!).