Mapping bass to feedback-trail zoom or symmetry scale makes the tunnel pulse with the low end

In the psychedelic style, the preferred reactivity target is the bass band (a.fft[0]), which corresponds to the kick and sub — the most physically felt musical events. The feedback-trail zoom rate or the symmetry scale are the appropriate destination parameters, because they vary the depth and size of the tunnel or mandala in lockstep with low-end hits. This creates the heavy, smeary, envelope-following reactivity that the psychedelic register demands. The qualifier ‘envelope-following’ is important: the reaction should track the sustained bass energy, not snap on individual transients (which would require onset detection, not currently available). The term ‘heavy and smeary’ characterizes the quality — not crisp and precise, but slow, deep, and overwhelming.

Examples

Hydra: src(o0).scale(()=>1.005+a.fft[0]*0.008).out(o0) — bass drives zoom rate, creating a tunnel that zooms deeper on bass hits.

Assessment

Distinguish between an ‘onset-triggered’ bass reaction and an ‘envelope-following’ bass reaction in a psychedelic visual. Which is achievable in this rig? Describe the mapping (band, parameter, typical gain range) for a psychedelic feedback tunnel reaction.