Which formats and operating systems does Quell support?

Quell ships as AU and VST3 for macOS 11+ (Apple Silicon and Intel) and Windows 10/11. It runs in any DAW that loads AU or VST3, including Ableton Live, Logic Pro, FL Studio, Studio One, Cubase, Bitwig, Reaper and Pro Tools.

Free download · pay what you want

Quell — the free spectral resonance suppressor.

Q: Is Quell really free?

Yes. Quell is a free download — it is offered pay-what-you-want, so you can get the full plugin for $0 with no credit card, or tip any amount to support development. It is the complete plugin with no trial limit or watermark.

Q: What is a spectral resonance suppressor?

A spectral resonance suppressor, also called a dynamic resonance EQ, analyses audio across the whole frequency spectrum and dynamically reduces harsh, ringing resonant peaks the moment they occur — without permanently dulling the source. Quell does this automatically in real time.

Q: What can I use Quell on?

Quell works on any source with harsh or ringing resonances: vocals and sibilance, boxy or honky acoustic and electric guitars, ringing snares and drums, piercing cymbals and hi-hats, room tone, and full mix busses.

Q: How is Quell different from a normal EQ?

A static EQ cuts a fixed frequency all the time. Quell is dynamic and spectral: it only reduces a resonance while it is actually ringing, then lets the frequency through again — keeping the source natural while removing harshness.

Quell hunts down harsh, ringing resonances and tonal build-up across the spectrum in real time — so vocals, guitars, drums and cymbals stay smooth and controlled. The full plugin, free.

Free $0 · pay what you want Full plugin · AU & VST3 · macOS & Windows · instant download · no credit card

Download Quell free ▶ Watch the demo

No credit card Full plugin, no limits AU & VST3

Real-timeresonance detection

$0no card needed

Made for everything that rings

One plugin for every harsh resonance

Harsh vocals & sibilance Boxy & honky guitars Ringing snares & toms Piercing cymbals & hi-hats Resonant room tone Muddy mix busses

What's inside

A smarter way to de-resonate

Quell is the real plugin, free. Load it on a track and hear harshness disappear — surgical, dynamic resonance control that never dulls the source.

Real-time resonance detection

Quell continuously scans the whole spectrum and clamps resonant peaks the instant they ring out — no manual sweeping, no guesswork.

Dynamic & transparent

It only reduces a frequency while it's actually harsh, then lets it through again — removing ring and harshness without thinning the tone.

Built for any source

Vocals, acoustic & electric guitar, drums, cymbals, room tone and full busses — one tool for every harsh resonance in the mix.

Sensitivity & depth

Dial in exactly how hard Quell reacts — from gentle polish on a delicate vocal to aggressive control on a ringing snare.

See what it tames

A clean spectral display shows exactly which frequencies are being suppressed, so you always know what Quell is doing.

Light on CPU

Efficient processing means you can run Quell across your whole session — multiple instances without slowing your DAW down.

Three steps

From harsh to smooth in seconds

Download & install

Grab the free installer for macOS or Windows, run it once, and Quell appears in your plugin list as an AU/VST3 effect.

Drop it on a track

Insert Quell on the harsh vocal, guitar, drum or buss that's ringing. It starts analysing the spectrum immediately.

Set & forget

Set sensitivity and depth to taste. Quell tracks the resonances and suppresses them in real time as the performance plays.

Why it matters

Studio-grade resonance control — for free

Dynamic resonance suppression is usually a premium effect. Quell makes it free, so it can live on every channel in every session.

Doing it by hand

The slow way

Sweep a narrow EQ band to hunt each resonance
Static cuts dull the source even when it isn't harsh
Resonances move — your fixed bands don't follow
Minutes of tweaking on every single track

With Quell

Automatic · free

Detects and tames resonances automatically
Dynamic — only acts while a frequency is harsh
Follows moving resonances across the spectrum
Set sensitivity once — done in seconds, on every track, free

Compatibility

Runs everywhere you work

AU & VST3 in any host that loads them — on Windows, Apple Silicon and Intel Macs.

Price: Free — pay what you want ($0+, no credit card). The full plugin, no trial limit.
Formats: AU (Audio Unit) and VST3 — both included.
macOS: macOS 11 Big Sur and later · Apple Silicon (M1–M4) native & Intel.
Windows: Windows 10 and 11 · 64-bit · VST3.
Hosts: Ableton Live, Logic Pro, FL Studio, Studio One, Cubase, Bitwig, Reaper, Pro Tools and any AU/VST3 DAW.
Delivery: Instant download via Gumroad — signed installers for macOS and Windows.
Maker: Built by Reinhardt Buhr / Buhr Audio — clean, musical, CPU-friendly plugins.

Free forever

Get Quell free

Download the full Quell spectral resonance suppressor for $0 — pay what you want, no credit card. Tame harsh resonances in your very next session.

Download Quell free Watch the demo ☕ Buy me a coffee

From the blog

Get the most out of Quell

Free guides on taming harsh resonances and mixing cleaner — featuring Quell.

Guide

The best free resonance suppressor plugin in 2026

What a spectral resonance suppressor does, why it beats a static EQ, and how to get one free.

Read → Tutorial

How to fix a muddy mix (free)

Low-mid buildup, masking and ringing resonances — a clear, repeatable process to clean it up fast.

Read → Tutorial

How to remove harsh resonances from vocals (free)

A step-by-step walkthrough for smoothing harsh, sibilant, ringing vocals with a free plugin.

Read → Explainer

Resonance suppressor vs dynamic EQ

How each works, the key difference, and when to reach for which — plus a free option.

Read → Comparison

The best free Soothe2 alternative in 2026

How dynamic resonance suppression works, what a free option can do, and how to get one.

Read → Explainer

Free dynamic resonance suppression, explained

Dynamic resonance suppression used to be premium-only. Here's how to do it for free.

Read →

FAQ

Good to know

Is Quell really free?

Yes. Quell is a free download, offered pay-what-you-want — get the full plugin for $0 with no credit card, or tip any amount to support development. There's no trial limit and no watermark; it's the complete plugin.

What is a spectral resonance suppressor?

A spectral resonance suppressor (also called a dynamic resonance EQ) analyses audio across the entire frequency spectrum and dynamically reduces harsh, ringing resonant peaks the moment they occur — without permanently dulling the source. Quell does this automatically, in real time.

Which formats and operating systems are supported?

Quell ships as AU and VST3 for macOS 11+ (Apple Silicon & Intel) and Windows 10/11. It runs in Ableton Live, Logic Pro, FL Studio, Studio One, Cubase, Bitwig, Reaper, Pro Tools and any AU/VST3 host.

What can I use Quell on?

Anything with harsh or ringing resonances: vocals and sibilance, boxy or honky guitars, ringing snares and toms, piercing cymbals and hi-hats, resonant room tone, and full mix busses.

How is Quell different from a normal EQ?

A static EQ cuts a fixed frequency all the time. Quell is dynamic and spectral — it only reduces a resonance while it's actually ringing, then lets the frequency through again, so the source stays natural while the harshness is removed. Learn more in our guide to dynamic resonance suppression.

Where do I download Quell?

Click any Download Quell free button on this page. It opens the Quell page on Gumroad, where you can set your price to $0 and download the installer for macOS or Windows instantly.