I'm experimenting with my VU1 dials, they aren't for music, but for Gold or ETF prices they are great.
This dial shows my average paid gold price and the current spot in relation to it. If gold spot is +5 to +10% the display will go red and i'll sell some to take profits. If it's below -5% the LED will turn green and i'll buy some to lower my average price:
Contribute to extreme-sysadminning/vu-dial-gold development by creating an account on GitHub.
github.com
Some test images, grey scale without and with dithering:
Some more pics with Yamaha remote for scale:
They aren't fast enough for music, but you could use them to indicate the status of a volume knob or input or something.