Maxon AF-9 Auto Filter

General

The AF-9 Auto Filter is Maxon's take on the legendary Mutron III envelope filter and, we have to admit, its organic wah-sounds live and breathe Seventies funk and soul and have a vocal-like quality. Next to the Range switch to determine the frequency range for the effect, the AF-9 features sensitivity and peak parameters that are tweaked via two dedicated controls. Using the Sensitivity control, you can decide how hard you need to strike a note before the filter responds, while the Peak control is used to boost the frequency range set using the Range switch and emphasizes the 'quack' effect of the filter - similar to the resonance parameter of a filter pedal or synth.

Vintage Auto Filter: Up & Down Wah

The filter can work both ways and drive the sound up or down. In Down mode, the sound is best described as a traditional 'wah', while in Up mode, the effect is reversed and sounds like a wah-wah pedal being moved upwards. Since the AF-9 can switch between three filters (high pass, band pass and low pass), it's compatible with almost all instruments and works especially well with a bass guitar to bring Bootsy Collins-style funk to the stage.

• Please note: A power supply is not included.