DOD 440 Envelope Filter
They say:
Speak with vowel-like sounds, cry with slow-filter sweeps that react to your pick attack
The 440 has all of the quack, squee, squonk, chicka, mwomp, and weeeooow, that you could ask for. It works equally well on guitar, bass, and keys. Use out for funky chordal work, simulated wah, or trippy drawn-out filter sweeps. While 440 is a faithful recreation of the vintage 440, the addition of the up/down toggle gives it a modern sonic twist.
