Recently, I ran into a problem. I don't know if this is a bug or not, so I posted it here...
I use SFZ as a soundfont player in MPT. Everything worked fine until I tried to change the volume. I had some orchestral strings on different midi channels of the same plugin and tried to fade them out with v60, v56 etc. commands (the "volume envelope" command didn't work). I eventually reached v04 (and stopped the instrument with a == ) and all worked well until I tried to play the song again.
Now, it didn't work. The strings and even the organ (which I hadn't manipulated at all) had their volume at extremely low levels. It seemed like the volume commands had permanently set the whole SF player plugin volume down to 4 as I had put it in the fadeout. I even removed the volume commands and still it didn't play the instruments at full volume. I put v64 commands in the beginning of the song, but it didn't work. Only by restoring an earlier save I could return to status quo.
Is the volume command meant to work like this, setting the whole plugin's volume once and for all? If it is, how can I control the volume of a single channel with a soundfont instrument in it?
This is indeed a new feature you're experiencing.
Any VSTi will now be able to respond to a volume command. This wasn't possible in the past, you see.
There are 2 distinctions.
1. Playing a note with a volume command -> Sets the velocity for that note, which was always possible.
2. Playing an empty row with a volume command -> Sets the wet/dry ratio of the recently played plugin, which is new.
Basically you've set the wet/dry ratio of the plugin to 04 meaning that its almost muted. Playing a note with a volume command will not change the wet/dry ratio, but instead change the velocity of that note. In order to set the wet/dry ratio while you have a note, either setup a Zxx macro to do this, and use Z7F as value or attach your plugin to a new channel, and just put a v64 volume in that row without a note playing.
Or optionally, it might also be possible to set the v64 in an earlier pattern where the note already died playing.
To control volume with SFZ you can use its hardwired MIDI CC, I don't remember exactly which, but you can find CC list somewhere in your SFZ folder or on the manufacturer's site. I know I'm not helpful but some time ago I had this problem.
Thanks for the replies.
The empty channel volume control worked for me. I don't know a thing about midi macros or CC's and didn't find out anything by messing around in MPT, so obviously I couldn't use those solutions.