@audio/eq-lowshelf

RBJ low-shelf filter — boost or cut below a corner frequency

npm install @audio/eq-lowshelf

import lowShelf from '@audio/eq-lowshelf'

RBJ Audio-EQ-Cookbook shelf biquad, via @audio/biquad. One section, no cascade — fc is the shelf's mid-point (half the gain is reached there), Q sets slope.

let params = { fc: 200, gain: 3, fs: 44100 }
for (let buf of stream) lowShelf(buf, params)

| Param | Default | | |---|---|---| | fc | 200 | Corner frequency, Hz | | gain | 0 | Shelf gain, dB (positive boosts, negative cuts) | | Q | 0.707 | Shelf slope (1 = RBJ "shelf slope = 1", steepest monotonic; lower is gentler) | | fs | 44100 | Sample rate, Hz |

Pass the same params object across successive calls — coefficients and filter memory are cached on it and only rebuilt when fc/gain/Q/fs change, so state carries across block boundaries automatically.

Use when: warming or thinning below a corner frequency — low end, rumble region, weight; the bottom half of a Baxandall-style tone stack.

Part of @audio/eq — the eq family umbrella.

MIT © audiojs