It rings! (louder!)
That’s it! I had it all backward. the nano was powered by the +5 from the driver, and the ln298 logic was powered from the however many volts I was ramping it up with. Now, nano has power from usb and ln298 logic has power from the nano’s +5V. And I can ramp up the power suply to max 31V to hear beautiful music, no problem! Yup, the EN pin is now connected to 5V 
Of course I still have a need to run it on battery, though. Perhaps I still need to go in the direction of @SteveMann ‘s transformer circuit? or a boost converter?
yes, I can:
And when it was still wholesome(ish):
Wonderful people, thank you!