Shure SM58

The Shure SM58 is a professional cardioid dynamic microphone, commonly used in live vocal applications. Produced since 1966 by Shure Incorporated, it has built a strong reputation among musicians for its durability and sound, and half a century later it is still considered the industry standard for live vocal performance microphones. The SM58 and its sibling, the Shure SM57, are the best-selling microphones in the world. The SM stands for Studio Microphone.

Like all directional microphones, the SM58 is subject to proximity effect, a low frequency boost when used close to the source. The cardioid response reduces pickup from the side and rear, helping to avoid feedback onstage. There are wired (with and without on/off switch) and wireless versions. The wired version provides balanced audio through a male XLR connector. The SM58 uses an internal shock mount to reduce handling noise.

A distinctive feature of the SM58 is the pneumatic suspension system for the microphone capsule. The capsule, a readily replaceable component, is surrounded by a soft rubber balloon, rather than springs or solid rubber. This gives notably good isolation from handling noise, making it a popular microphone for stage vocalists. It is a key feature of Shure's high-end microphones intended for hand-held stage use, rather than stand or instrument miking.

The SM58 is unswitched, while the otherwise identical SM58S model has an on-off switch on the body. Other variants refer to the accessory kits supplied with the microphone: -LC models are without a cable, -E models include a 5/8" screw thread adapter for the stand mounting clip.

The SM58, and other Shure microphones, have been extensively counterfeited. Most of these counterfeit microphones are at least functional, but have poorer performance and do not have the pneumatic suspension. There are many other subtle details which can reveal most of these fakes.

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Wikipedia