VirSyn have a good reputation in the iOS world and have done for a long time now. Bark Filter is the latest in their long line of apps and is an interesting addition to their portfolio. I haven’t tried it as yet, but the combination of a filter and compressor is something I’d be interested in trying out.

Here’s the app in VirSyn’s words:

The multi band filter in Bark takes the approach to match the reception characteristic of the gate where all sounds must pass through: the human ear. The ear behaves as if it contains a bank of filters, each filter passing frequencies within their respective critical band. Two tones apart more than the frequency dependant critical bandwidth are perceived as separate tones. For this reason Bark contains a filter bank with 27 very steep bandpass filters matching the critical bandwidth characteristic of the human ear. In fact, the human ear have also its own built in multi band compression system which are based on the critical bands.

Why the name Bark ? The Bark scale is a frequency scale on which equal distances correspond with perceptually equal distances. Above about 500 Hz this scale is more or less equal to a logarithmic frequency axis. Below 500 Hz the Bark scale becomes more and more linear.

Multiband compressors can act differently on different frequency bands. The advantage of multiband compression over full-bandwidth compression is that unneeded audible gain changes or “pumping” in other frequency bands is not caused by changing signal levels in a single frequency band.
Bark can act both as single band compressor and with up to 27 bands in multiband mode by linking critical bands.

The linear phase filter bank with its steep filter slopes can be used for unusually pronounced filter effects too…


  • Multi band dynamic range compressor with up to 27 bands
  • Variable number of compressor bands (1..27)
  • Threshold/Ratio Attack/Release and Makeup Gain
  • Linear phase precision filters for maximal transparency
  • Real time pre/post processing calibrated spectrum analyser
  • AudioUnit for AUv3 compatible hosts.
  • Inter-app audio compatible effect.
  • Audiobus 3 compatible with state saving.
  • Low latency live usage with mic and headphones.
  • Audio recorder

Luckily enough Doug from the SoundTestRoom has already made us a video of Bark Filter in action.

Bark Filter requires and iPhone5s / iPad mini 2 / iPad Air or better. The app is on an introductory price of $6.99