The "Default Synth" in Band-in-a-Box is supposed to be set up as a default or baseline synth for all songs, such that if you open any song it's expected to "just work". If you change settings in the plugin, BIAB expects that you want those settings changed for all songs. This works much the same way as if you had an external hardware synth like a Sound Canvas, which is what the MIDI implementation in BIAB was built for.

I think it's a good idea to be able to save the default synth settings per song, so I've put in a feature request under id# 5081.

The better thing to do for now would be to change the plugin for each individual track, as individual track plugins and settings are saved into each song file.

Originally Posted by Jim Fogle
PG Music provides two more.
On Windows we provide CoyoteWT as the default synth, plus VSTSynthFont is included in the BB\Data\Libx64 folder and can be added like any other plugin. It's also possible to use the Microsoft GS Wavetable Synth, which is built into Windows. For macOS we use the Apple DLSMusicDevice plugin which is built into macOS.

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