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 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 its 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, one reason for its being a popular microphone for stage vocalists. Microphones with this feature are intended primarily for hand-held use, rather than on a stand or for instrument miking.

The SM58 is unswitched, while the otherwise identical SM58S has a sliding on-off switch on the body. Other suffixes refer to any accessories supplied with the microphone: when a cable is provided, the model is actually SM58-CN, while the SM58-LC has no provided cable; the SM58-X2u kit consists of the SM58-LC and an inline X2u XLR-to-USB signal adaptor (capable of providing phantom power for condenser microphones, and offering an in-built headphone jack for monitoring).

Specifications

 * Type: Dynamic (moving coil)
 * Frequency Response: 50 to 15,000 Hz
 * Polar Pattern: Cardioid, rotationally symmetrical about microphone axis, uniform with frequency
 * Sensitivity (at 1,000 Hz Open Circuit Voltage): −54.5 dBV/Pa (1.85 mV); 1 Pa = 94 dB SPL
 * Impedance: Rated impedance is 150 ohms (300 ohms actual) for connection to microphone inputs rated low impedance
 * Polarity: Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
 * Connector: Three-pin male XLR
 * Net Weight: 298 g

Awards

 * In 2008, for the second year running, the SM58 microphone won the MI Pro Retail Survey "Best Live Microphone" award.
 * In 2011, Acoustic Guitar magazine honored the SM58 with a Gold Medal in the Player's Choice Awards.

Counterfeiting
The SM58, and SM57, 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.