The MD 421 is a well-known Sennheiser microphone of proven reliability and performance for many years now. Due to its excellent quality it has been used for every kinds of applications.
The MD 421-U has a black housing and balanced XLR connector. The 421 U4 and U5 versions differ in the thread on the removable microphone clip. Version U4 has an interchangeable thread, while U5 has a thread with a fixed 3/8-inch dimension for the American market.
The MD 421-U is provided with a 3-pin Cannon plug (XLR). It is, as the other two models, a low-impedance mic which is symmetrically wired. A roll-off ﬁlter is provided. Two versions of the MD 421-U are available: MD 421-U-4 with adapter for ⅜-inch threads and MD 421-U-5 with adapter for ⅝-inch x 27G threads. The MD 421 N and the MD 421-2 are available in light grey heavy-duty ﬁnish. The models MD 421-U-4 and MD 421-U-5 feature a matt-black housing.