Got it! Thanks to Chris and the community for the help.
It's late, so tomorrow, I'll add a few notes here for anyone else who stumbles across the thread with a similar problem, and I'll mark Chris' post #34 as the Solution, unless he or other folks think #10 would be a better choice. It depends on the nature of the problem: in my case, #34 is the answer, but for someone using a library other than the old Tone one, #10 would be a good reference.