Sennheiser MD 421

The Sennheiser MD 421 is a German cardioid dynamic microphone, widely used for speech in broadcasting and for music in live concerts and the recording studio.

Its wide frequency response (30–17,000 Hz ± 3 dB) exceeded the former Hi-Fi standard and came close to the performance of condenser microphones.

The MD 421 offered a smooth, closed plastic housing without ports, retaining its directional pickup pattern no matter how it was held.

[1] At the end of the 1950s, Fritz Sennheiser directed engineers Paul-Friedrich Warning and Johann-Friedrich Fischer to develop a new microphone.

This high-pass filter has proven itself both when used as a vocal microphone (suppression of the proximity effect and plosives) and when broadcasting and recording outside to reduce wind noise.

The characteristic shape of the MD 421 was part of the appearance of countless press conferences, political speeches and television reports well into the 1990s.

But it excels at its intended job: Jazz guitarist Brian Tarquin referred to the ubiquitous American Shure SM57 when he described the MD 421 as "an SM57 on steroids... probably one of the most diverse mics ever made.

"[5] The MD 421 can withstand high sound pressure levels, and it can record a wide dynamic range.

Various solutions suggested by engineers include ways to prevent movement of the quick-release mechanism, for instance with a small zip tie.

The microphone is intended for tight locations such as a drum kit or in front of a guitar amplifier on a small stage.