The MINI MU is a compact version of the classic Mutron III envelope filter. It retains the same fat and funky filter sweeps but in a smaller enclosure. It features an active clean gain stage and an additional “in between” position on the range switch. The MINI MU can run on +/-9V with the included charge pump, eliminating the need for a special power supply or two batteries.

The development of the MINI MU began with the demand for an autowah pedal based on the original Mutron III. The design started as a clone with a volume control and underwent numerous tweaks to improve the filter’s response, increase headroom, and enhance versatility.

The MINI MU excels at adding quack and funk to your tone but is not suitable for slow filter sweeps. It utilizes optocouplers with a faster reaction time, which was a crucial aspect of the original circuit.

The controls on the MINI MU include:

– LEVEL: Provides control over the volume, ranging from off to 20dB of gain with the added clean boost at the end of the circuit.
– GAIN: Sets the pre-gain before the filter, affecting sensitivity and range of the filter sweep. It has been modified to offer maximum clean headroom.
– PEAK: Adds feedback to the filter, increasing bite and resonance in the autowah’s sweep.
– DRIVE: Determines the direction of the filter sweep. Up starts low and goes higher, while Down starts high and goes lower.
– MODE: Sets the type of filter – HP for high pass (brightest), BP for band pass, and LP for low pass (fattest).
– RANGE: Adjusts the overall frequency range of the filter sweep.
– INTERNAL CONTROL: A trimpot on the main board allows for tuning the sensitivity of the optocouplers, adding sensitivity or adjusting the filter’s frequency response.

Summary created by AI from the original source.