Janus

Janus is a linear-phase Linkwitz-Riley crossover VST3 plugin with both a high-pass and a low-pass filter on a single instance — a two-faced design where each face can be independently enabled and tuned.

The filter is implemented as a symmetric FIR. Drop one instance on each parallel band of a multi-way speaker, set both to the same cutoff frequency and slope, and the sum is mathematically flat. No phase rotation between bands. No comb filtering on summation.

Key Features.

— Symmetric FIR. The HPF and LPF sides are mathematically complementary. Two instances tuned to the same cutoff sum back to a flat magnitude — for active multi-way speaker designs where bands must recombine without artifacts.

— Linkwitz-Riley slopes from 1 to 48 dB/oct in decimal steps. Not just the conventional 12 / 24 / 48 dB/oct — pick any slope between 1 and 48 in decimal increments, tuning the crossover region precisely.

— Latency modes (Eco / Normal / High-Res). Each trades pre-ringing against processing latency. Linear-phase filtering inevitably comes with pre-ringing; Janus exposes the trade-off as an explicit user choice and reports latency honestly to the host for plugin delay compensation.

— Per-face enable. One instance can act as a clean linear-phase HPF, a clean LPF, or a band-pass — useful in single-band roles, not just full crossover chains.

DESIGNED FOR Multi-way active loudspeakers, biamped / triamped systems, mastering chains where phase coherence matters, and anywhere a steep filter is needed without phase rotation.

DESIGN PRIORITIES Phase coherence between bands and minimized audible pre-ringing — both treated as non-negotiable. Every parameter in the UI is in service of those two goals.

SYSTEM REQUIREMENTS — VST3-compatible host (DAW or plugin host) — Windows 10+ (64-bit) — macOS 10.15+ (Intel or Apple Silicon — universal binary) — 44.1 – 192 kHz sample rates.

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