VINAIcore Manual

01Overview

VINAIcore splits the incoming signal into three frequency bands with Linkwitz-Riley crossovers at 200 Hz and 3 kHz (24 dB/oct, phase-coherent). The low band runs mono for a tight, centered punch; mid and high stay stereo to keep width and air intact. Each band carries its own envelope follower and tanh saturation, with a DC blocker on every path, then the bands recombine into a final safety clipper.

The whole treatment is governed by the Adaptive Loudness Core and driven by one control. AMOUNT modulates every band's saturation threshold together. From 0 to 100% it drives low, mid and high deeper into their curves in a single move. No band balancing, no threshold hunting: turn it up until it sits, then leave it.

02The interface

• AMOUNT knob (center): the one control; 0–100% drives the saturation threshold of all three bands at once.
• Band metering (LOW · MID · HIGH) shows the 200 Hz / 3 kHz split, with low running mono and mid/high stereo.
• Final clipper switch selects the master-stage ceiling: CLIP · ROUND · OFF.
• Pre / Out section holds Pre Low Cut, Pre In Gain, Out Gain and Bypass to set level around the curve.

03Knobs & buttons

04The final clipper

05Under the hood

Signal flow

Pre Low Cut → Pre In trim → 3-way Linkwitz-Riley split → per-band envelope-driven tanh saturation → band recombination → DC-blocked sum → oversampled safety clipper → Out trim. The bands are reconstructed by complementary LR4 filters, so the magnitude sum is flat and phase-coherent across both crossover points. Everything downstream of the split runs sample-accurate; the only added delay is the clipper's lookahead, reported to the host for plugin-delay compensation.

• Crossovers are 4th-order Linkwitz-Riley (24 dB/oct), implemented as cascaded Butterworth sections, at 200 Hz (low/mid) and 3 kHz (mid/high). LR4 sums to a flat magnitude response with an allpass-equivalent phase, so reconstruction is gap-free.
• Band routing sums the low band to mono before saturation for a centered low end; mid and high remain fully stereo to preserve width and air.
• Per-band saturation gives each band its own envelope follower feeding a tanh saturation stage. AMOUNT modulates the tanh threshold of all three stages simultaneously, so a single control drives low, mid and high deeper into their curves in lockstep.
• Safety clipper: the recombined sum hits a master-stage clipper running 8× oversampled (polyphase up/down conversion with anti-imaging / anti-aliasing filters). CLIP is a soft-tanh ceiling, ROUND a soft-cosine knee, OFF bypasses the clip and lets the bands run hot into the next stage.
• DC blocking puts a first-order DC blocker (~7 Hz corner) on every band path, so asymmetric saturation can't accumulate a DC offset before recombination.
• Latency is ~3.5 ms total lookahead, reported to the host for full PDC; the plugin reports its exact sample latency so the session stays in time.
• Output integrity means the post-sum signal is spectral-purity gated: silence in yields silence out, with no idle tone, hiss or dither floor injected by the processor.

06Measured

Measured in-house (headless host + numpy/scipy), 48 kHz.

07Specifications