Free · Discrete transistor-based EQ
EQ5500
Studio grade – discrete transistor-based EQ
A faithful emulation of a legendary American EQ design featuring op‑amps and distinctive Proportional-Q circuitry. Smooth, musical tonal shaping at subtle settings. Tighter, more aggressive response as gain increases.
VST3 · AU · Standalone · macOS + Windows
- Windows VST3 · Standalone · 64-bit
- macOS VST3 · AU · Standalone
- Mac Apple Silicon + Intel · 10.13 or later
- Price Free
Play it
The real panel.
The real curves
This is the plugin's own window, its rendered knobs and keys, and the screen above it runs the plugin's own model. Drag a knob, step through the factory presets, unlink the channels, switch CLEAN to CHARACTER, and watch a boost get narrower as it grows.
Computed live from the plugin's model, both channels, the bands and HP-FILT relative to 0 dB. The screen is for this page; the plugin itself is the panel.
What's on the panel
Proportional-Q
Pushing emulation
to a new level
EQ5500 faithfully emulates one of the most sought-after EQ modules in recording and mixing history, capturing its distinctive tonal character and musical response.
At its core is a Proportional-Q design, where the filter bandwidth narrows as the amount of boost or cut increases.
EQ5500 is engineered to faithfully reproduce the original hardware's frequency response, extending into the highest frequencies of the spectrum to preserve the detail, clarity, and character of the original design.
- +1 dB
- +3 dB
- +6 dB
- +12 dB
The model
Accurate advanced
modeling
To capture the original unit, we ran extensive frequency sweeps through the hardware at every stage of the signal path. From the deepest lows to the top of the audible range, each sweep mapped exactly how the circuit responds, not just at flat settings but across all kinds of boost, attenuation, bandwidth and frequency combinations.
Instead of guessing the response between a handful of points, the model is fitted to the real machine and rebuilds its response live as you turn the knobs. The result is an EQ that reacts like the hardware, wherever you set it.
EQ5500
Real. Versatile.
Precise. Free.
Free. No catch. Click, get the key by email.
VST3 · AU · Standalone · macOS + Windows
Specifications
- Formats: VST3, AU and standalone app (64-bit)
- Windows and macOS (universal: Intel and Apple Silicon, macOS 10.13 or later)
- Mono or stereo. Click-free switching on every step and detent, state saved with the session
- Runs internally at 176.4 kHz or above, so the top detent is a real bell
- Your presets are plain text files:
%APPDATA%\MTHRBORD\EQ5500on Windows,~/Library/Audio/Presets/MTHRBORD/EQ5500on macOS - Completely free to download and use forever
EQ5500 is a model of a hardware design, made from our own measurements. It is not affiliated with or endorsed by the maker of the original.
Long live the underground.