a Sennheiser MD 421-II dynamic microphone

Sennheiser dynamic microphone, part of Butch Vig's array of microphones for the massive guitar overdubs in Siamese Dream. Mics were placed by cranking Billy's amp up to full gain, boosting the headphone send, then moving the mics around using the guitar echo's phase-shifting hiss as a guide. The 421 accented the sound's midrange.
[product page (MD-421 II)]