Spectral Agent is back with a vengeance. Version 2 retains the core Master/Yielding engine that received praise in V1, with some key advancements: new interaction modes, improved latency, and tighter control across the board.

From a top-level, Spectral Agent:

Compares frequency data between tracks.
Determines frequency clashes.
Dynamically implements notch filters to favor lead tracks.

Structurally, the plugin works as a full-mix unmasking manager by giving you the power to create an ecosystem of Master/Yielding interactions across all your tracks.

Windows and macOS-compatible (VST3 and AU)

New in Version 2

Negotiate mode - a zipper merge for "equal priority" tracks that just need some separation, without placing one over the other
Ducking mode - very low latency ducking envelope, ideal for fast percussion transients. Achieving ~4ms detection at 60Hz with no lookahead; gets faster as you move up the spectrum (sub-3ms everywhere above 100Hz).
Slidable EQ Bands - dynamic EQ bands, newly equipped with per-track knob multipliers: perfect for fine-tuning across the spectrum
Groups - Controlled Master/Yielding/Negotiating groups, as well as 3 custom groups: each one with per-group knob multipliers, designed for DAW automation and batch modifications

All complemented by a GUI upgrade.

~Tune the knobs in ducking mode to define your envelope(s)~

~Tinker with your EQ bands to enhance some frequency regions, while protecting others~

~Use custom groups to automate (and even invert) master/yielding pairs~

The Ecosystem Concept

Put up to 64 instances of Spectral Agent on the tracks or buses in your mix, and they will automatically broadcast data to each other (no sidechaining necessary). Select one of the other tracks, and the analyzer window will display an overlay of the tracks' frequency data. The plugin will identify peaks, as well as frequency collision points between the two tracks.

You can then begin to determine which tracks should lead (by setting them to Master), yield (by setting them to Yielding), or simply negotiate — the new equal-priority mode that nudges two tracks apart instead of picking a winner. The analyzer window will display a new Green curve displaying post-processed data on the Yielding track. Even if a track is Yielding to another, it can still be Master in another interaction. This is where the "ecosystem" concept starts to come alive — with the layering of priority settings and complex hierarchy structure.

Each per-pair interaction gets its own parameters to dial in: notch depth, sensitivity, Atk/Rel, freq band, etc. Spectral Agent limits the number of notches and uses a weighted priority algorithm to determine the most optimal placement of the notches at any given time — to prevent a track from getting completely crushed if it's Yielding to several others.

Under the Hood

A priority ecosystem, not static cuts: a lock-free internal registry lets instances share spectral data in real time. A Master broadcasts its dominant peaks; a Yielding instance deploys targeted, transient-responsive notches exactly where — and only when — a collision happens. When the Master stops playing, the notches release and the Yielding track gets its body back.
Intelligent slot allocation: seven general-purpose hysteresis-controlled notch slots plus one dedicated Bass slot. When several tracks compete for the same space, a weighted priority algorithm decides who wins the frequency.
Acoustically-tuned envelopes: attack and release scale automatically across the spectrum, so you avoid artifacts whether you're ducking below 100Hz or above 10kHz.
Precision visual feedback: an 80-band log-scale analyzer draws the local input, the remote track's spectrum, and the post-processed output at once, with DSP-accurate collision markers.
Nominal CPU tax: a fully lock-free audio callback with all heavy FFT analysis offloaded to a background thread — built for high track counts.

Per-Pair Controls

When you link two tracks, these controls apply strictly to that specific relationship — so the unmasking behavior stays local to the pair:

Depth (0–12): how aggressive the gain reduction gets. Low values are gentle presence management; high values are deep, surgical separation.
Q (0.5–8.0): scales the bandwidth of the dynamic cuts above the frequency-optimized baseline.
Sensitivity (0.2–4.0): shifts the detection threshold. Higher widens the net to catch subtle overlaps; lower demands a tighter, more direct collision before anything triggers.
Attack & Release (0.1–8.0×): multipliers on the adaptive timing baselines, for tailoring the notch response to the envelope of the source material.

Whether you're overhauling your mix for clarity on vocals, or subtly edging guitars over pianos, Spectral Agent offers a scalable solution for prioritized unmasking.

Still on Version 1?

The original Spectral Agent is still up on Gumroad for existing customers who need to re-download or get support: Spectral Agent V1 · V1 demo. Questions about either version — immanentaudio@gmail.com.