I faced a similar conundrum many (many, many) years ago when I needed to demo the 5-channel analyser I made for a university project. Eventually I settled on Alphaville's "Big in Japan". That alone probably gives you a rough idea how long ago this was...
@tomii: ...remember, "full on" is pretty danged obnoxious. Even with a diffuser.
Thise NeoPixels are really bright for sure -- I'm very much looking forward to seeing what they look like shining through my Fresnel lenses -- of course if they are too bright I can always PWM them down :-)
@Tom-ii: You should see some of my videos on using those - I find that anything above 50 (out of 255) starts to get pretty obnoxious. Also, if you're controlling brightness based on some other parameter, you'll likely want to "linearize" it.
Very interesting video -- I'll remember that for the future -- but in my case I don't think I'll be controlling brightness in quite this way.
I can't say for sure until I start playing with it, but I think my LEDs will always be full-on -- I'll be using the amplitude of each frequency band to control the "height" of the LEDs in the associated column.
@Antedeluvian: My problem is remebering to allow for power dissipation.
Ha -- I already thought of this -- there's a panel that goes on the back -- it's got a series of 1" holes across the bottom and across the top -- so I think I'll be able to get sufficient draft to keep evereything cool.