Some businesses or homes might be the perfect fit for a large wall sized graphic equalizer. Unfortunately I couldn't find any solutions online during my first few searches… However I did find this small homemade graphic equalizer.

Something like that could be fun to put together with my son. Let's try googling for something else… How about something like "oversize LED array" and let's look at the result:

Possibly an oversized graphic equalizer could be constructed using these waterproof LED strips. Sounds like a project!