Leaky4

Leaky4 is a stereo tool for controlled inter-channel bleed. It lets you take a filtered portion of one component of your stereo signal (Left, Right, Sum [Mid], or Difference [Side]) and leak it into another. Nothing more complicated than that — and that simplicity is exactly what makes it powerful.

The story behind Leaky

The idea for Leaky came from a specific mastering problem. I was working on a track with an incredible low end, but everything between 20–30 Hz was out of phase. Every tool I tried made things worse — the magic in the sub simply disappeared. Out of that frustration, I built the first version of Leaky. By leaking only the left channel in that range, while leaving the rest of the spectrum untouched, the low end locked in perfectly. The track suddenly sounded exactly the way it was intended. That single experience became the reason Leaky exists.

How I use it today

These days, I use Leaky in almost every project where the stereo image needs adjustment — whether it's widening or narrowing. One of its biggest strengths is the ability to widen the stereo field without affecting the Sum (Mid), which can make a mix feel more open without losing its center. On the other hand, narrowing the stereo field in a specific band can help center a vocal or create a stronger phantom center, giving the track more focus and punch.

How it works

Choose a Leak From source (L/R/Sum/Difference), set a Filter to define the frequency band, optionally adjust Phase Rotation or add Delay to control how the leak interacts, then send it to the Leak To destination (L/R/Sum/Difference).

Key controls

• Leak From / Leak To – pick the source and destination (L, R, Sum/Mid, Difference/Side).
• Filter – define the frequency range that leaks through.
• Phase Rotation – rotate the leak to control how it interacts with the destination.
• Delay – shift the leak in time to avoid phase problems.
• Anti-Flutter – removes transients from the leak, making it easier to blend where it's sent.

What's new in Leaky4 vs Leaky3

• Phase Rotation on the leak path for finer control of interaction.
• Delay as an alternative way to avoid phase issues.
• Anti-Flutter to remove transients from the leak, for smoother blending.

Straight talk: Leaky doesn't "process" audio in the broad sense. It simply routes filtered portions of the signal between channels. That's why it can be both transparent and transformative.

Price & availability

• Patreon: available to active Patrons from $6/month.
• One-time purchase: $30 via the Patreon shop (includes all minor updates within the 4.x cycle).