My first step would be to save a copy of the file using a slightly different name. For example, if the file is called My_Song.mgu, save it as My_song2.mgu.
Once I have done the above, I can freely experiment with different ways of doing it because I can always get back to the original file now that a backup exists.
I'd try....
1. Change the patch.
If that didn't work....
2. Unfreeze, change the patch, refreeze.
If that didn't work...
3. Generate the song with the track frozen, unfreeze, change the patch, play the song without generating, freeze the track.
If you are using the Windows version of the software, then that means that you also have Realband.
Realband would be a much better place to work with the file because, unlike BIAB, it does not automatically regenerate the tracks and changes, because of this, can be applied without having to worry about losing things.
Also, because Realband has 48 tracks, it's possible to copy a track to a second track so that you have an easily available backup if needed.
Is this a melody that you've created or is it a file from the internet?
If it's based on a midi file from the internet, it could have patch changes embedded in it. This would then always be in place If this is the case, these need to be removed.
I'd like to try and replicate your problem. To do this, though, I need more information.
Firstly, under preferences, turn off the "Autoname track labels" as shown on the upper image below. This will make BIAB use the old track names that don't change and so helps me identify what track you mean.
1. With the above autoname option off, what track contains the notation that you want to keep?
2. Have you loaded a midi file from the internet in some way?
3. Can you please take a screen shot of your chordsheet view when in Standard Mode. To do this....
Enter Standard mode by pressing CTRL+T (if you are in Full screen mode).
Press printscreen to copy the desktop view to clipboard.
Open Paint (software that comes with windows).
Press CTRL+V to paste the clipboard contents into Paint.
Save the files as a jpg. Do not modify the image in any way.
Follow the instructions at the below link to post the image in this thread. (The lower image below shows the view that I'd like see from your computer and BIAB.)
I only used the Slap Bass as an example to show you that it's possible to change the sound. If you follow what I did above, you'll be able to change the sound to whatever you want.
Okay, it looks like the bass track has an embedded patch change at bar 29, which is why you are getting the electric bass.
So do this to fix it (it's a number of steps, but will take all of a few seconds to accomplish):
1. From the top line menu, select "Edit, Copy Special, Copy/Move Tracks".
2. Since your soloist track is empty, this should work without affecting the rest of your song. Select the Bass track as the source track and the soloist track as the destination track. You should be able to leave all channels selected.
3. Leave "Merge with existing data on track" unchecked. Click on "OK - Do it".
4. Click the Play button, but you can stop after the initial count-in. Just need to make sure everything is on the Soloist track. The Soloist track will have the wrong patch setting. So, just right click on the "Soloist" track radio button (it's the one between the one labeled "Piano" and "Thru"), then from the popup menu, select "MIDI Instrument Patch", then select "Select General MIDI Patch". From the list, choose the Acoustic bass patch you want (probably 33 - Acoustic String Bass). Click on OK and then you will get a "Question" box that says: "Soloist has embedded patches in the track, example: Fretless Elec. Bass at bar #29. OK to remove all these patches?". Select "YES".
5. Now right click on the Bass track radio button and select "Track Settings, Unfreeze Bass 1 Track".
6. Now select, "Edit, Copy Special, Copy/Move Tracks" again. But this time, select the soloist track as the source and the bass track as the destination.
7. This will copy over the soloist track to the bass track and refreeze it.
8. Now select "Soloist, Edit Soloist Track, Form, Kill Entire Soloist Part". Then click "Yes" when asked to erase MIDI data.
9. Save your file (new name if you wish).
Your bass track should now only play the acoustic bass patch.
Don't know why there is an embedded patch change, but this should fix it for you.
John
Laptop-HP Omen I7 Win11Pro 32GB 12TB SSD Desktop-ASUS-I7 Win10Pro 32GB 12TB SATA
But to remove the embedded patch, you must copy the "sick" track to a new track. Only so when you change the patch , you will get a "Question" box that says: "Soloist has embedded patches in the track! "
This is an impossible and unpredictable workaround !!!!! arghhhhh
Again, don't know why there was an embedded patch change, and in general it shouldn't happen (although there are some styles that have different patches assigned when switching between the A and B substyles - didn't see that in this case).
I'm glad it worked for you.
John
Laptop-HP Omen I7 Win11Pro 32GB 12TB SSD Desktop-ASUS-I7 Win10Pro 32GB 12TB SATA
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