Constant MAX_ELEMENTS 

pub const MAX_ELEMENTS: usize = crate::dsp::SPECTRUM_BINS; // 64usize

Largest element count a [spectrum] table may ask for — the band count itself, because above it the 64 → N reduction stops being a partition of the array. The loader validates against this, and the render layer sizes its per-element scratch to it (Plan 0034 Phase 4), so the two cannot disagree.