Klevgränd has brought us a very wide range of iOS apps and Brusfri is yet another good example of this. Apparently Brusfri means “Noise free” in Swedish. Which I did not know before this.

Klevgränd describes Brusfri as

A highly advanced audio noise reducer, packed into a simple and straight-forward interface. It is very well suited for cleaning up noisy audio recordings, while retaining sound quality. Unlike many other noise reducers on the market, Brusfri doesn’t mess with audio phasing to suppress noise (a technique that often comes with audible side effects). Instead, multiple fine-tuned gates are used to silence unwanted noise.

Of course noise reduction can be useful in lots of situations, especially in the iOS worlds with mics that aren’t perhaps as good as they could be. One very useful feature in Brusfri is its “Learn” function. Press “Learn” during a couple of seconds of isolated noise to record a “profile” for noise. You could open Brusfri in any AUv3 compatible host, find a region in the recording that only contains noise and play it. Tap and hold the “LEARN” button for a short while (a second will be enough).
When the LEARN button is released, Brusfri starts reducing noise.

There are also parameters that affect the noise reduction algorithm:

  • ATK / THRS / REL (Attack Time / Threshold / Release Time)
  • Threshold – basically determines how much noise to be removed. A lower value means more reduction
  • Attack and Release sets the time it will take for the reducer to start working.
  • EDGE: Controls the reduction aggressivity. A lower value gives a smoother reduction.
  • HPF: Reduces low frequencies.
  • HIGH: Compensates high frequencies by boosting them.

NOTE! Brusfri is CPU intensive and iPhone 6S / iPad AIR 2 or better is recommended. We highly recommend freezing/bouncing tracks to reduce CPU usage. Brusfri is currently AUv3 only, which means it won’t work in stand alone mode. It must be used as a plugin

Brusfri costs $7.99 on the app store now (includes a 33% launch discount)