pub const LOW_WINDOW_SIZE: usize = 8192;Expand description
Second, longer FFT window feeding the bands below the crossover (~171 ms at
48 kHz). Chosen by measurement in Plan 0048 Phase 1 against one rule — 4096
first, 8192 only if 4096 still leaves sub-bass bands bin-starved. Of the 20
bands below the crossover, 4096 leaves all 20 still one bin wide and 8192
leaves 8, pulling the unresolved boundary down from 246 Hz to 76 Hz. See
fft::BandLayout and ADR-0049; the_long_window_was_chosen_by_measurement
pins all three candidates.