Multi-Q

Multi-Q is a universal equalizer that combines three legendary EQ designs into one powerful plugin — completely free.

Overview

Instead of buying separate plugins for different EQ tasks, Multi-Q gives you everything in one place:

• Digital — Modern surgical precision with dynamic EQ
• British — Classic console character
• Tube — Vintage vintage passive tube warmth and musicality

Switch between modes instantly while keeping your session settings. Each mode has been carefully crafted to capture the essence of the original hardware.

Digital Mode

Modern parametric EQ with per-band dynamics and dynamic processing built in.

Features:

• 8 fully parametric bands
• Per-band dynamic EQ (threshold, attack, release, range)
• Multiple filter types per band
• Linear phase option for transparent processing
• Low-pass filter with multiple curve types
• Real-time spectrum analyzer with pre/post display

Dynamic EQ: Each band can respond dynamically to the input signal. Set a threshold, and the band will boost or cut based on the audio level — perfect for de-essing, dynamic resonance control, or frequency-dependent compression.

British Mode

Classic console EQ emulation — the same engine as our 4K-EQ, integrated into Multi-Q.

Features:

• 4-band parametric (LF, LMF, HMF, HF)
• Brown (E-series) and Black (G-series) modes
• High-pass and low-pass filters
• Bell/Shelf switching on LF and HF bands
• Analog saturation with Drive control
• Per-band harmonic modeling

Brown vs Black:

• Brown — Musical, broad curves with transformer warmth
• Black — Surgical, tight response with proportional Q

Tube Mode

Vintage passive tube EQ with tube saturation — the legendary “boost and cut at the same frequency” trick.

Features:

• LF Boost and Attenuation with selectable frequency
• HF Boost and Attenuation with bandwidth control
• Mid Dip/Peak section for presence shaping
• Tube Drive control for harmonic saturation
• Passive EQ curves that interact musically
• Vintage teal panel aesthetic

The vintage passive tube Trick: Boosting and cutting at the same low frequency creates a unique curve that adds punch without mud — a technique used on countless classic records.

Technical Specifications

Digital Mode

• Bands: 8 fully parametric
• Filter types: Bell, High/Low shelf, High/Low pass, Notch, Band pass
• Dynamic range: Up to 24dB boost/cut per band
• Linear phase: Zero phase distortion option

British Mode

• Topology: Console-accurate biquad filters
• Saturation: Multi-stage analog modeling
• Q behavior: Fixed (Brown) or proportional (Black)

Tube Mode

• Curves: Passive LC filter emulation
• Tube model: 12AX7 triode saturation
• Interaction: Authentic boost/cut frequency coupling

Performance

• CPU usage: ~2-4% per instance (varies by mode)
• Latency: Minimum phase: ~32 samples / Linear phase: ~2048 samples
• Memory: ~15MB per instance

Installation

Linux

VST3: ~/.vst3/Multi-Q.vst3
LV2:  ~/.lv2/Multi-Q.lv2

Windows

VST3: C:\Program Files\Common Files\VST3\Multi-Q.vst3

macOS

VST3: ~/Library/Audio/Plug-Ins/VST3/Multi-Q.vst3
AU:   ~/Library/Audio/Plug-Ins/Components/Multi-Q.component

Beta Status

Multi-Q is currently in beta (v0.9.0). Core functionality is stable, but we’re still refining:

• Additional presets
• UI polish and responsiveness
• Documentation and tooltips

Please report any issues on GitHub.

Open Source

Multi-Q is open source under GPL-2.0. View the source, report issues, or contribute on GitHub.

Multi-Q combines emulations inspired by classic British consoles and vintage American tube EQs. This project is not affiliated with or endorsed by any hardware manufacturer.