Modular Multi-Effect Processor
23 studio-quality effects, now with a frequency-selective Ducker on every slot and the master bus, UI scaling, an expandable Master strip, and a redesigned Saturator. Route, stack, and shape your sound with complete creative freedom.
Build updated 2026-05-28: Ducker stereo fix and tightened-up defaults. If you grabbed an earlier 1.3.0 prerelease, please re-download. See changelog.
What's New
Frequency-selective ducking on every slot and the master bus, scalable UI, an expandable Master strip, and a redesigned Saturator.
Ducker — on Every Slot and the Master Bus
A frequency-selective ducker with a parallel broadband path lives on every slot's Out cluster and on the Master strip. Set Freq + Q to carve out a band, then dial Spectral and Amount against shared Attack, Hold, Release, Threshold, Range, Stereo Link, and up to 10 ms of Lookahead. Mode picks between Level (classic level-tracking sidechain) and Transient (each onset fires a one-shot duck-and-recover — held chords don't pin ducked). A per-Ducker Trigger Source picker keys each slot off Routed In, Self, Main Input, or any earlier slot; the master can key off Main, the pre-FinalMixer wet bus, or any single slot.
UI Scale — 75% to 200%
A new UI Scale submenu in the logo right-click menu lets you make the entire editor uniformly larger or smaller at six tiers (75% / 100% / 125% / 150% / 175% / 200%). Sits on top of the existing dynamic resize: pick a scale tier, then drag the editor corner as usual. Scale is per-user, not per-project, and clamps to the display so the resize handle stays reachable.
Expandable Master & Draggable Divider
Click Out in the signal flow diagram to expand the Master panel full-width, the same way clicking slots 1–4 expands those. A thin hairline in the gap between slot 4 and Master is now draggable to widen Master at the slots' expense or vice versa; double-click resets to the symmetric default. Useful as the Master strip accumulates controls (Ducker just landed) and you want more room, or want to step back and audition four slots side-by-side at different proportions.
Saturator Mode Redesign
The Shape knob now does something meaningful in every mode. Soft Clip: sweeps knee hardness from gentle tanh rounding to hard clipping. Cubic: an odd-harmonic polynomial with Shape adding higher odd harmonics — 2× oversampled. ArcTangent: a tilt filter before the nonlinearity makes Shape sweep frequency emphasis (warm ↔ bright). Asymmetric: Shape sweeps from fully symmetric (odd harmonics) to maximum pos/neg difference (even harmonics). Transfer-curve and harmonic-bar visualizations updated to match.
Why Spectrus?
4-Slot Modular Architecture
Chain up to 4 effects in series or parallel. Each slot has independent level control and wet/dry mixing for precise sound design.
Flexible Signal Routing
Route any slot to receive from the main input or any previous slot. Create complex effect chains with ease.
23 Studio Effects
From classic modulation to lush reverbs, tape delays to spectral processing, including 10 reverbs led by Cloud Reverb's granular engine and the Stutterus tempo-synced glitch repeater.
Dark & Light Themes
Switch between a polished dark theme and a bright light theme to match your DAW or your mood. Every control, meter, and visualizer adapts instantly.
Per-Slot Tone & Stereo
Dedicated Air (sparkle) and Body (warmth) knobs on every slot, plus a new Stereo In control on every effect that continuously blends between classic mono-sum processing and full stereo. No more choosing between vintage character and width.
938 Factory presets
Save and recall your favorite configurations. Organize presets into folders. Lock slots to preserve settings across preset changes.
Low CPU Usage
Optimized DSP code means you can run multiple instances without bogging down your session.
Try All 23 Effects Free
Demo mode gives you full access to every effect (including all 16 Pro effects) so you can explore everything before you buy. A gentle periodic fade is the only reminder.
Slot Lock, Drag & Drop, Copy & Paste
Lock any slot to preserve its settings while browsing presets. Drag slots to reorder them, or right-click to copy and paste an effect configuration between slots.
Cross-Platform & Multi-Format
Available on Windows, macOS, and Linux. Supports VST3, AU, LV2, and CLAP. Works with all major DAWs.
23 Effects Included
7 effects free forever. Unlock all 23 with Pro.
Modulation
- Chorus
- Vintage Chorus PRO
- Flanger
- Phaser
- Tremolo
- Ring Modulator PRO
- Rotary PRO
- Sample & Hold PRO
Delay
- Echo
- Tape Delay PRO
- Spectral Delay PRO
- Stutterus PRO
Reverb
- Plate Reverb
- Prism PRO
- Bloom PRO
- Ember PRO
- Shimmer PRO
- Freeze PRO
- Velvet Room PRO
- Velvet Hall PRO
- Glacier PRO
- Cloud Reverb PRO
Utility
- Saturator
Choose Your Version
Free
- Chorus, Flanger, Phaser, Tremolo
- Echo, Plate Reverb, Saturator
- 4-slot modular system
- Flexible routing
- Preset system
- Demo mode: all 23 effects & 938 presets
Periodic fade — not for production use
Pro
- All 23 effects
- 4-slot modular system
- Flexible routing
- 938 Factory presets
- Free updates
Free vs Pro at a glance
Both versions run on Windows, macOS, and Linux in VST3, AU, LV2, and CLAP formats.
| Feature | Free | Pro |
|---|---|---|
| Effects | ||
| Modulation | 4 of 8 | All 8 |
| Delay | 1 of 4 | All 4 |
| Reverb | 1 of 10 | All 10 |
| Utility | 1 of 1 | All 1 |
| Core features | ||
| 4-slot modular architecture | ✔ | ✔ |
| Flexible signal routing | ✔ | ✔ |
| Dark & Light themes | ✔ | ✔ |
| Per-slot Air, Body & Stereo In | ✔ | ✔ |
| 938 factory presets | ✔ | ✔ |
| Free updates for life | ✔ | ✔ |
| Pro unlocks | ||
| Try all 23 effects | Demo mode, periodic fade | Always, no fade |
| Production-ready, uninterrupted audio | — | ✔ |
| Price | $0 | $49 $29.40 one-time |
System Requirements
Operating System
Windows 10+
macOS 11+ (Intel & Apple Silicon)
Ubuntu 22.04+ / Linux x86_64
Processor
Intel Core i5 or equivalent
RAM
4 GB minimum
Plugin Formats
VST3 · AU · LV2 · CLAP