I have been working with the MSGEQ7 and made a VU-Meter for my home stereo system.
It uses a stereo pot for level control. Now it can be used on a low audio level like from a PC as well as on high audio level from a beefy amplifier.
The following links describe the schematic with strip board design:
and a very basic sketch how to control the strip with only one data line:
My coding skills are limited, so I’m hoping that outstanding artists like Mat Bettinson can create some cool visuals based on it