“The MXR Envelope Filter is a professionally designed, competitively priced tone modifier which enables you to create a wide variety of “wa-wa” sounds. The Envelope Filter is a voltage-controlled, low-pass filter in which the upper cutoff frequency is determined by the amplitude, or level of the input signal. The louder the signal, the higher the cutoff frequency.”
“The loudness of the signal therefore controls the “brightness” of the sound. Two controls are provided on the MXR Envelope Filter. A Threshold control varies the sensitivity of the filtering action. An Attack control varies the attack time of the filter. At full clockwise position, the filter responds almost instantaneously.”
“Longer attack times serve to create a “wa” at the beginning of each note played. The MXR Envelope Filter may be used with any electric keyboard or stringed instrument, including guitar, bass, piano, and clavinet. The Envelope Filter will add variety and expression to both solo and accompanying performances.”
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