Music Unfolding has released OttoPhilter and xTrem, the latest additions to the Twister Series of AU plug-ins for Mac OS X.

OttoPhilter is an auto/touch wah filter with LFO control and sub-octave generation and a second auto/touch wah filter on the sub-octave. There's a level meter tied to the touch wah sensitivity to help you adjust OttoPhilter to suit your playing dynamics. OttoPhilter has two driven resonant filter sections - one on the input signal and one for the generated sub-octave. The filters sweep by using triggered envelopes or tracking the input signal or using LFOs.

OttoPhilter costs $19.99 and is also available as part of Music Unfolding's new Guitar Player's Bundle.

xTrem is a tremolo unit capable of a range of tremolo shapes; it works as a mono or stereo tremolo. In mono mode, the left channel controls are active. The two channels are fully independent except for the tremolo depth setting, this gives it the capability of producing some interesting panning/tremolo combinations.

xTrem is free.