Ondinha

Ondinha Split EQ

An EQ that hears the difference between a hit and a held note.

Split EQ divides your audio into a transient layer (attacks, clicks, noise bursts) and a tonal layer (sustained, pitched sound). Every band has its own gain for each, so you can add bite to the snare without the cymbal wash getting brighter.

Runs on macOS, Windows and Linux: VST3 everywhere, plus Audio Unit on the Mac.

Download for macOSDownload for WindowsDownload for Linux

Version 1.0.2, released 8 October 2026. macOS 17.5 MB, Windows 2.7 MB, Linux 5.1 MB. Changelog

Ondinha Split EQ window: transient and tonal EQ curves over a live spectrum, six bands, layer meters and the match bar

What it's for

Masters

More kick punch in the lows on the transient layer only, more air up top on the tonal layer only. The top opens up and the hats stay where they were.

Drums

Bring the stick attack forward without boosting the room ring. Pull the ring down without dulling the hit.

Tighter wide mixes

Narrow the transient layer and keep the tonal layer wide: punch in the middle, space around it.

Matching a reference

Load a reference track, or feed it to the side-chain, and learn. Each layer gets its own match curve, so your drums can take the record's click while the sustain takes its body.

Features

  • Six bands (low shelf, four bells, high shelf), each with a transient gain and a tonal gain of up to 18 dB
  • Its own window: both layers' curves over a live spectrum, drag points to shape them
  • Per-layer level and stereo width (0 to 200 %)
  • Reference match per layer, from a file or from the side-chain while the track plays
  • Transparent when flat: the two layers add back to the input exactly
  • Analog-matched EQ curves, no cramping near Nyquist
  • Latency reported to the host, so your DAW keeps everything in time

Controls

ControlRangeWhat it does
BandsLow shelf, 4 bells, high shelfFrequency, Q or slope, transient gain and tonal gain (+-18 dB) per band
Split-12 to +12 dBMoves the line between what counts as transient and what counts as tonal
Separation0 to 100 %How strictly the two layers are kept apart
Level-36 to +12 dBTransient and tonal layer level
Width0 to 200 %Transient and tonal layer stereo width
Match0 to 100 %, smoothing, rangeHow much of the learned reference curve each layer takes
Output-18 to +18 dBOutput level

Factory presets show up in your DAW's preset menu: Master: punch low, tonal air.

How it works

Split EQ runs harmonic / percussive separation (after Fitzgerald, 2010) on a short-time Fourier transform. For each frequency bin, the median over about 110 ms is the tonal level, and the median across frequency of each bin's rise above it is the transient level. A soft mask divides the two. The masks come from both channels together, so the stereo image stays put, and they always sum to one: with every band flat, the layers add back to the input exactly.

Specs

Formats
VST3, Audio Unit (macOS)
Latency
about 96 ms at 48 kHz, reported to the host
Side-chain
Yes, for live reference matching
Price
Free
macOS
11 or later, Apple Silicon and Intel: VST3 and Audio Unit
Windows
10 or later, 64-bit: VST3
Linux
x64: VST3

Works in Ableton Live, Logic Pro, Reaper, Bitwig Studio, Cubase, Studio One, FL Studio and other VST3 or AU hosts.

Install

macOS

  1. Unzip the download.
  2. Copy Ondinha Split EQ.vst3 to ~/Library/Audio/Plug-Ins/VST3 and Ondinha Split EQ.component to ~/Library/Audio/Plug-Ins/Components.
  3. The plug-ins aren't notarized yet, so clear the download flag once in Terminal: 
    xattr -dr com.apple.quarantine ~/Library/Audio/Plug-Ins/VST3/"Ondinha Split EQ.vst3" ~/Library/Audio/Plug-Ins/Components/"Ondinha Split EQ.component"
  4. Rescan plug-ins in your DAW. Logic Pro scans Audio Units when it starts.

Windows

  1. Unzip the download.
  2. Copy the Ondinha Split EQ.vst3 folder to C:\Program Files\Common Files\VST3.
  3. Rescan plug-ins in your DAW.

Linux

  1. Unzip the download.
  2. Copy the Ondinha Split EQ.vst3 folder to ~/.vst3.
  3. Rescan plug-ins in your DAW.

Changelog

1.0.2

  • The plug-in window and the Ondinha themes use the logo's colours: the transient layer in rose, the tonal layer in sky blue.

1.0.1

  • The plug-in window wears the Ondinha palette: the transient layer in coral, the tonal layer in sky blue, so the two layers never look alike.
  • Without the Ondinha app installed, the plug-in opens in the charcoal (dark) look.

1.0.0

First release: the transient / tonal split EQ with six bands, per-layer level and width, and reference matching per layer.

All releases on GitHub

Questions

Is Ondinha Split EQ free?

Yes. Download it from this page or from the GitHub releases.

Which DAWs does it work in?

Any host that loads VST3 plug-ins, or Audio Units on a Mac: Ableton Live, Logic Pro, Reaper, Bitwig Studio, Cubase, Studio One, FL Studio and others.

Why does it add latency?

Telling a hit from a held note needs a short look ahead (about 96 ms at 48 kHz). The plug-in reports it, and your DAW's delay compensation keeps every track in time.

macOS says the plug-in can't be checked. What do I do?

The plug-ins aren't notarized yet. Run the xattr command from the install steps once, then rescan plug-ins in your DAW.

Source and issues

Found a bug, or a host where it misbehaves? Open an issue on GitHub with your DAW, its version and your operating system.