alt Hacker NewsPhyllotaxis spirals (derived from the golden angle) make such an elegant coordinate space for radial audio visualization because they avoid the density distortion of concentric circular rings.
The trickiest part in these builds is usually balancing transient response with temporal smoothing so the LEDs don't devolve into jittery noise during busy frequency passages. Curious if you're doing per-bin decay filters on the FFT or handling dynamic gain normalization upstream?
I'm still not perfectly happy with the audio response, tbh. But it mostly suffices.
I experimented with both approaches, and landed on mixing the band energy normalized by global energy vs. per-bin max energy, with a very arbitrary coefficient that seems to work. I also keep a few copies of the levels per band with different rates of decay, so I can add features in the sketches which should be sensitive to transients, vs. features which can rely on slower rates of change.
Not at all an expert in any of this and it was a lot of trial and error, still lots of room for improvement.