GPO5's Concert Grand Harp is a really nice instrument, but it's far too loud. It goes well into the red at the slightest provocation.
I'm convinced that this is an error, not a deliberate decision.
Find the instrument file called `Lyon and Healy Harp KS 1.sfz`. Line 84 has `volume = 16`.
The SFZ specification says 'values should be between -144 and 6, though many players can use values above 6'.
I’ve changed it to 4, which seems to work well for my needs. You may need to authorise permission to write to the file. (On the Mac, BBEdit will sort this for you.)