The award-winning Moog MF-101 Low Pass Filter is a successor to the original modular Moog synths, containing two modular functions: voltage-controlled low pass filter and an envelope follower. Use the MF-101 to create dynamic-controlled filter sweeps for your guitar, bass, keys, or essentially any instrument that can be plugged in. You can even choose between brighter 2-pole filter frequency and the deeper 4-pole - the MF-101 tries to give you as many options as possible in building your tone.