The original SM7, photographed in 1973. Photograph/media licensed by and courtesy of Shure Incorporated.


The Shure SM7B: Five Decades In, Still Shaping the Soundtracks of our Lives

By Sarah Jones

Chances are, if you’re reading this, you have a Shure SM7B in your studio. The iconic dynamic mic, revered for its warm, smooth vocal reproduction, is one of most prolific microphones of the past two decades, used by legions of artists, engineers, and podcasters to capture some of the most important recordings in recent history.

It’s helped shape albums by Michael Jackson, Metallica, Bob Dylan, and the Rolling Stones. The Red Hot Chili Peppers, Sam Smith, Logic, John Mayer, My Chemical Romance, and Black Pumas record with it. It’s the mic behind thousands of podcasts, including such blockbuster hits as 99 Percent Invisible and Pod Save America. It’s also a mainstay in broadcasting and voiceover work. The SM7 is so popular here at Gearspace that there’s even an entire joke thread dedicated it. (Some highlights: “Knock, knock. Who's there? SM7B. SM7B who? SM7 be the best mic ever.” “You know that voice in your head that tells you right from wrong? Well, it was recorded with an SM7.”)

The SM7 was introduced in 1973, but its origin story begins much earlier than that. Shure was founded in 1925 as a radio parts mail-order company, but by 1932 was manufacturing microphones. This pivot came during an era of great growth in broadcasting and recording: Radio was exploding in popularity, with radios found in four out of five homes in America by the end of the 1930s. Meanwhile, recording studios had transitioned from acoustic recording to electrical recording. Suddenly, everyone needed microphones, and Shure was ready to deliver.



A 1973 flier for the SM7. Photograph/media licensed by and courtesy of Shure Incorporated.


Before 1939, single-element dynamic microphones were nondirectional. RCA and Western Electric, the biggest players at the time, developed unidirectional microphones, but they had to incorporate two different elements in the same housing, which made them bulky and expensive and prone to inconsistent performance.

At Shure, a 25-year-old transducer engineer named Benjamin Bauer found a way to design a unidirectional microphone with a single element, by adding rear openings into the dynamic element and incorporating a phase-shifting acoustic network.



A 1977 ad in Billboard magazine. Photograph/media licensed by and courtesy of Shure Incorporated.


This breakthrough, which became known as the Uniphase Acoustical Network, earned Bauer the first of more than 100 patents and paved the way for the design of Shure’s first dynamic microphone, the legendary Unidyne Model 55. That mic quickly caught the attention of both heads of state and popular performers including Frank Sinatra, Ella Fitzgerald, and perhaps most notably, Elvis Presley, earning it the nickname “the Elvis mic.” Unidyne microphones are among the most recognized mics in the world, and are still in production today.

In the early 1950s, Bauer designed a smaller version of the Unidyne, the Unidyne II, which offered the advantage of not obscuring performer’s faces on television. Increasingly, singers wanted to hold mics as they moved around. Up to this point, all Shure unidirectional mics were side-address models. In 1959, Bauer’s protégé, Ernie Seeler, broke new ground with the Unidyne III capsule. This innovation led to the introduction of end-address microphones, which meant more uniform, stable polar patterns and greater gain before feedback. (The Beatles were pioneer users of the Unidyne Model 545, taking a set of loaners—complete with windscreens held in place with rubber bands—out on tour in 1965.) In the late 1960s, this element became the foundation of the ubiquitous SM57 and SM58 and informed the design of the SM7’s forerunner, the SM5 broadcast microphone.

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SM57, SM58, SM7B: What’s the Difference?

The SM57, SM58, and SM7 all share a similar acoustic network based on the Unidyne III element. Here’s how Shure explains the differences between the SM7B cartridge and the SM57/SM58 cartridge design:

The SM7B diaphragm is slightly different and optimized for increased low-end response;

The larger housing of the SM7B allows for a larger rear volume behind the cartridge which extends its low end response;

The internal shock mount of the SM7B is optimized to reduce mic stand vibrations, while the shock mount in the SM57/SM58 is optimized to reduce noise in handheld applications.
The SM5, introduced in 1964, was first marketed as a boom microphone; it became popular in radio and film studios, and was adopted as an on-air broadcast mic. But the two-pound, ten-inch behemoth was costly and cumbersome, making it impractical for many studios. According to Shure legend, acoustical engineers were given a mission: Build the best microphone possible, with no limitations on size or cost. The result was the SM7, which looks almost exactly like the modern SM7B available today.

The SM7 was designed for universal studio applications. Its Unidyne III capsule exhibits frequency peaks between 2 kHz and 7 kHz that make it well suited for human voice, but that’s just part of the story: The microphone’s large housing captures extended low end and imparts a rich tone to voices. Compared to the SM57, the SM7 has wider, more neutral frequency response; it includes a highpass filter to reduce low-frequency rumble and a mid-frequency attenuator to flatten its inherent presence peak.


The Shure SM7B’s frequency response. Photograph/media licensed by and courtesy of Shure Incorporated.


Most of the SM7’s earliest adopters were voiceover studios and radio stations; legendary DJ Wolfman Jack was said to be one of the first users. The mic was slow to gain momentum outside broadcasting, but in the late 1970s, began to catch on in studio applications. Because the SM7 is a dynamic mic, it’s less sensitive to low-level high-frequency sounds than condenser mics, making it a great choice for capturing vocals while eliminating other sounds in the environment. Meanwhile, its wide frequency response and ability to withstand high SPLs make it ideal for recording a range of sources from vocals to horns to guitar amps to kick drums.

Mick Jagger recorded with the SM7—often using it to dual-record vocals with a condenser mic—and David Bowie and George Harrison had SM7s in their mic cabinets. Producer Chris Kimsey (Rolling Stones, Peter Frampton, Peter Tosh) says he always appreciated that singers can get in close, telling performers “you can eat it.”



The Shure SM7B’s cardioid polar pattern. Photograph/media licensed by and courtesy of Shure Incorporated.


Everything changed in 1982 when legendary recording engineer Bruce Swedien used an SM7 on Michael Jackson’s Thriller sessions to capture Jackson’s vocals for “P.Y.T. (Pretty Young Thing),” “Billie Jean,” and other tracks. Swedien was a big fan of the SM7, owning six; in his memoir, In the Studio with Michael Jackson, he called it one of his “absolute favorite microphones." Soon, engineers everywhere started recording with the SM7, hoping to capture some of that multi-Platinum magic.

Throughout the 1990s, the SM7 was used exclusively by audio engineers. Yet despite its growing popularity in studios, sales remained flat, and the mic was in danger of being discontinued after 30 years. Then, somewhere around 2007, something surprising happened: SM7Bs suddenly started flying off the shelves. Podcasting was taking off like wildfire, and the emerging market created new demand for high-quality voiceover microphones. You can hear the SM7 in action on podcasts such as Snap Judgement, Song Exploder, My Favorite Murder, and Conan O’Brien Needs a Friend. (The Twenty Thousand Hertz podcast dedicated an entire episode to the microphone.)


Tips for getting the best performance out of an SM7B. Photograph/media licensed by and courtesy of Shure Incorporated.

A few years later, streamers and gamers started getting in on the action, and today, the SM7 can be found everywhere in live sound, broadcast, and recording.

The microphone hasn’t changed much over the years: In 1999, Shure introduced the SM7A, which added an improved yoke mount and incorporated a better humbucking coil, offering shielding against electromagnetic interference from CRT video monitors. In 2001 the SM7B debuted, featuring a larger windscreen.

Generations after its debut, the SM7B continues to play a key role in the recording of today’s biggest albums, capturing everything from vocals to drums. It’s been used on tracks by Jack White, Death Cab for Cutie, Metallica, and Green Day. It’s often favored in rock, thanks to its pronounced midrange and high-SPL capabilities, but you can also hear its imprint on recordings by Keith Urban, Maroon 5, Childish Gambino, and The Weeknd.

So, next time you grab your SM7B, consider the fact that you own a piece of recording history—and that you’re in great company. Learn more about the SM7B at Shure.com.