Resonant analog lowpass filter. Does the same job as moogerfooger MF-101, minus the drive button and exit controls, plus the ability to reverse, and certainly less expensive and much smaller!
Connectivity: input/ouput/9v/pedale expression.
True bypass with relay.
Made in New Orleans (so once a year they are flooded and it takes a bit to take back some of the prod orders)

UTILIZATION

The settings are quite sensitive and go from one extreme to the other: no sound too sound (Start taming the beast low volume on the amp ...), no filtering of self oscillation of the filter. Requires a bit of work to understand what is happening. Loses 50% of its use without expression pedal.

SOUND QUALITY

Construction: ok.
Sound quality: did the job requested.
Noise: ok beaches in "normal". When a setting of self-oscillation and bypassed, a slight repisse oscillating frequency is audible.
Saturates in extreme settings (normal. .. And given the level sent it better because it limits the volume "surprise" output of the amplifier)

Moogerfooger compared to MF-101, Iron Ether explained that the grain is a little less "soft" or more "acid", I have not checked.

OVERALL OPINION

As the name suggests it, it is a resonant low-pass filter, known more commonly by guitarist "auto wah" or "wha wha" fully customizable.
I use it with a guitar, but it is also good with a bass.
Uses:
- As an auto wha the pot "meaning" to adjust the sensitivity of the attack, the switch S / F allows a fast or slow response to the attack, the pot "freq" maximum frequency is reached, the switch up / down allows you to move the filter to the severe acute (normal wu-> ah) or acute downward (wha -> hoo!). All this is very funky.
- As wha wha, with an expression pedal, lowering the "meaning" to zero.
- As frequency generator by pushing the pot "res" after 3h (gaffe in volume).
- As a "synth" by plugging in a fuzz upstream, it's "WwiiinnzzzzWwiinnnzz" awesome!

In all cases it is a very nice tool that allows a large pallets and wha sounds crazy.