Knocktonal

Name: Knocktonal
Price: 39 USD
Author: Swivel Audio

by Swivel Audio · EQ · Note-based drum resonance EQ

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Knocktonal is a note-based resonance tool from Swivel Audio that tunes drums by boosting or cutting their resonances and overtones, without pitch-shifting.

MIDI input can move the target note in real time, and a limiter keeps boosts in check; it is $69 at Plugin Alliance or $39 on sale from Swivel Audio.

Best for: Drums, Drum Bus, Bass, Sound Design. Genres: Hip-Hop & Trap, Pop, Electronic & EDM, Rock & Indie.

Keywords: drums, MIDI-controllable, bass, kick, snare, 808s, bus processing, creative, drum bus, mixing, sound design, static, subscription, visual feedback.

What it does

Knocktonal is a drum-tuning EQ from Swivel Audio. Instead of re-pitching a drum, you pick a musical note and it boosts that root and its harmonic overtones, or cuts resonances that clash, for "note-based resonant drum tuning".

Resonance EQ: choose a note to push a root frequency and its even and odd overtones, with a Range dial, a Focus dial and a presence control for the harmonics.
Overtones and Octaves modes: Overtones boosts the full harmonic series; Octaves boosts only octave multiples of the note.
Subtractive EQ: Frequency, Cut, Q and Overtones controls to remove the drum's existing ringing first, giving a blank slate before you add the new note.
MIDI control: MIDI channel 1 sets the Resonance EQ note and channel 2 sets the Subtractive EQ frequency in real time, so tuning can follow a bassline or chord changes.
Resonance display: a visual display of the resonances being shaped.
Safety limiter: a built-in limiter and output volume keep big boosts from clipping.

Because it works as an EQ rather than a pitch shifter, the drum's transient and attack stay intact. Version 1.2.0 arrived with the Plugin Alliance release in August 2025. Plugin Alliance offers a 14-day trial, and it is included in the CORE and PRO subscriptions.

Source: Swivel Audio product page

When to use it

Knocktonal is the better pick when you think about drum tone in notes rather than hertz. You could do the same job with narrow bells in FabFilter Pro-Q 4, but Knocktonal places the root and all its overtones in one move and can follow MIDI, which Pro-Q 4 cannot. Unlike soothe3, which finds and tames resonances automatically, it lets you choose a note and boost it as well as cut. Compared with pitch-shifting a sample, it keeps the original attack and length of the hit.

Best for: fitting kicks, snares, toms and 808s to the key of a track, and MIDI-driven drum tuning that follows chord changes.
Genres: hip-hop, pop, EDM and rock.
Look elsewhere if: you need real pitch-shifting, a built-in tuner, or general-purpose EQ (Pro-Q 4, TDR Nova).
Tip: automate the Resonance EQ note for pitch-slide effects on kicks and toms (MusicTech).

What producers say

Reviewers see it as an innovative, focused tool for drum resonance, with a few missing conveniences.

MusicTech (Alex Holmes) gave it 8/10 and called it "an innovative new tool", praising the clear GUI, fast workflow and preserved transients.
Uses: MusicTech found it excellent on kicks, toms and snares, and useful as a MIDI-controlled creative effect.
Criticisms: no built-in bypass for A/B checks, no tuner, no frequency readout while setting the boost note, and a subtractive EQ that struggles with sounds that have several resonances.

MusicTech review

Where to buy

Swivel Audio: $39 (regular $69)
Plugin Alliance: $69
PluginFox: $69

Tutorials and reviews

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