Brusfri launched – Klevgränd add a noise reduction tool to their iOS music app collection

Download from iTunes App StoreI’ve reviewed a number of iOS music apps from Klevgränd Produktion here on the blog over the last year or two – Vandelay, SquashitSvep, RoverbEnkl, WeeelKorvpressor, PressIt,  Esspresso, Jussi, HaazePads and Baervvag amongst others.

A number of these are also available in an AU plugin format for these working on an OSX desktop system and Klevgränd took a pretty bold step a few months ago when the also added AU support under iOS; it was great to see… and, in every case, I’ve been impressed with the creative possibilities that these apps provide. In addition, the novel – and very streamlined – user interfaces are ideal for the AU format.

Klevgränd have launched a further app today – Brusfri – and this is something a little different from their audio effects and virtual instrument app offerings to date. Indeed, as Brusfri is essentially a noise reduction utility processor – something that I’ve not seen before under iOS – it is perhaps ‘something different’ full stop.

Brusfri – Klevgrand bring noise reduction to iOS.

As with all their recent releases, Brusfri is delivered in formats for desktop (AU, VST; available from Klevgränd’s website) and iOS (AU). Again, there is no Audiobus or IAA or standalone option under iOS; Klevgränd see AU as the future and so are focusing on that format. Under iOS, the app is universal, requires iOS9.1 or later, is a 17MB download and is launched at UK£7.99/US$7.99 price tag.

Software for doing audio restoration on the desktop is pretty commonplace and – in one form or another – has been around for many years, although, at it’s very best (iZotope’s RX options for example, it is not cheap). Brusfri uses a technique that’s found in many of those desktop utilities where you ‘play’ it a bit of the audio signal that contains just the noise element, it ‘learns’ the frequency response of that noise, and then removes that ‘noise’ from everything else that passes through it. So, if you have, for example, a vocal recording made with a somewhat hissy preamp/mic combination, Brusfri ought to be able to clean things up a bit and ‘subtract’ the noise element from the whole recording.

The app is AU only under iOS… and desktop version are available in the popular plugin formats.

Sampling the ‘noise’ simply requires you to hold down the large ‘ear’ icon for a few seconds in a section of the audio (or while monitoring incoming audio) that should be silent (and just contains the noise). Once you let go of this button, the app than takes the noise profile and subtracts it from the signal. You get some control over how that’s done with the ATK-THRS-REL controls (which control how fast the noise reduction is applied when a real audio signal is present and how loud the ‘real’ signal has to be in order to ‘pass’ through the processor). You can also apply a little bit of post-processing EQ via the EDGE, HPF and HIGH controls. Rather nicely, the display shows the exact values of these controls as you make any adjustments.

Anyway, Brusfri is very easy to use and, providing the noise you wish to remove is both consistent in nature (a regular hum or a buzz), and providing it is relatively quiet compared to the actual sound you are trying to record (or have recorded), then the app does a very respectable job without obvious ‘damage’ to the sound being repaired. That you can get this quality of noise reduction from such an inexpensive bit of software is really rather impressive.

It will be interesting to see if Klevgränd follow up this release with a similar app/plugin aimed at click, pop and crackle removal. This kind of audio restoration requires a different sort of processing algorithm but can also be very useful…..  Watch this space.

The launch price is 33% off what will be the eventual full price of the app for a short period. If you find yourself battling the occasional noise problem because of noisy equipment, microphone preamps that are not of the highest quality, or simply because you do location recording in less than ideal circumstances, Brusfri might be well worth having to hand in your iOS app toolkit. Check out the demo video below and then hit the download button to find out more via the App Store.


Download from iTunes App Store


  1. When I watched Klevgrand’s demo video, I thought “I REALLY need this”, as I often have to deal with noisy guitars, mikes and environments. I figured that if Brusfri works even half as well as the demo, it would be better than nothing…

    I bought Brusfri a couple of days ago, and have done a bit of testing with it. It’s certainly pretty effective, as long as you remember it’s intended to remove “consistent” noise (such as background hum and pickup hiss) and not “transients” (pops, clicks, etc.). I found Brusfri in the main does its job quite transparently, although on occasions I thought I could detect a slightly phasey/swimmy edge to the de-noised audio. This is common with other noise-cancellation utilities (Audacity’s can be especially bad for displaying this effect), but it may have been down to me using Brusfri poorly. More testing will be done :-)

    Remember that being an AU app, Brusfri can be added to tracks in Garageband as an FX insert (and I learned this week how to do that – in “Track Settings”). I tried this on my iPhone 6S with an electric guitar track, using a “distorted” amp preset which was suitably noisy. Adding Brusfri as an insert effect, it removed the noise almost completely; however, the guitar audio became a bit “choppy”, which led me to believe the iPhone 6S might not have the CPU “grunt” to handle the amp-simulation and playback with the noise-reduction, at the same time. Again, more testing needed?

    Overall, though, I think Brusfri is now one of my “toolkit” iPhone music-production apps, and I know I’ll be using it a *lot* in future. I just wish I could’ve “made a move” on the Mac AU plugin when it was 30 euros… I want it in Logic as well!

Speak Your Mind