Fascinated by music and audio technology since building a crystal radio set as a child, Michael Pettersen is now the Director of Corporate History at Shure. Employed at the audio company since 1976, Pettersen is a contributing author to the 1,550 page reference tome, “Handbook for Sound Engineers.”
In his personal life, Michael is a professional musician, published composer of choral arrangements, co-author of a biography about jazz guitarist Freddie Green, and a notorious raconteur.
Broadcast Beat’s Frank Beacham interviewed Michael Pettersen from his Shure office in Chicago.
Beacham: Shure was founded by Sidney N. Shure in 1925 as a supplier of radio parts kits. There’s obviously been a lot of history in the company through the years. What exactly does Shure’s historian do on a daily basis?
Pettersen: That’s a good question. This morning, I was consulting with our agent in Australia where there is a film being made about Robbie Williams, who’s a pop singer. They wanted to make certain that the proper period microphones are being used in the different scenes in the 80s and 90s. Each week I write what’s called an applications tip tech tip.
I’m also involved in Shure’s philanthropic arm. One thing a lot of people don’t realize is that when the Shures were alive, they were very, very generous with their wealth. They gave most of it away. And when they passed away, they wanted to make certain that the company continued to operate like that. Shure today is owned by a trust, which is held by the employees. The beneficiaries of the trust are humanitarian and educational not for profit organizations. So it varies from day to day, Frank, but that’s what is fun about the job.
Beacham: History makes good stories. One was the development of the first single element unidirectional microphone in 1937. I think it was branded the Unidyne.
Pettersen: Ben Bauer was the guy that invented that. He was hired by Mr. Shure in 1936, as a co-op student still in college. Within several weeks, it was clear he was a genius.
One of Bauer’s tasks was to come up with a way to make a unidirectional microphone with only a single element. The first one was crystal and the second was a dynamic with a moving coil. Bauer’s work literally changed microphone design.
About 95 percent of the unidirectional microphones in the world today use some variation of what Ben came up with. We applied for a patent, which we got in 1941. The first unidirectional single element microphones that we brought out were in 1939.
Beacham: That was the Elvis mic, right?
Pettersen: It was the large dynamic Elvis mic, the model 55. But there was a model a few months before that was called the model 730, which was a crystal microphone. There’s a famous photo of Billie Holiday with that circular microphone, as opposed to the birdcage mic design.
Beacham: Isn’t a version of the Elvis mic still made today?
Pettersen: That’s correct. We made the larger one from 1939 to 1951. And then we brought out the smaller version, which we still make. In effect, one of those Elvis mic models has been in production since 1939.
Beacham: There is a rumor that the design of the Elvis mic came from the front grille of an Oldsmobile.
Pettersen: It was based upon the front-end grille of a 1937 Oldsmobile Coupe Six. I don’t know if Mr. Shure owned that specific model, but I do know he drove Oldsmobiles because in our archive, we have a receipt for when he bought one. He was obviously a fan of the car. If you look at the front end of a 1937 Oldsmobile Six Coupe, it is exactly what a Unidyne microphone looks like.
Beacham: During World War II, Shure made many mics and headsets for the military, and Mr. Shure apparently wrote in a memo “those screws, washers and other small parts mean the difference between life and death to millions of fighting men in the widespread battle lines of the allied forces.”
When the war ended, Mr. Shure decided to keep using military specifications for its peacetime products. He determined that it resulted in lower scrap rates during manufacturing, fewer product returns and better reliability. Do you see that decision as a key factor in the company’s later success?
Pettersen: Yes, absolutely. That was a pivot point for us. It could have been very easy to say, okay, the war is over, let’s get rid of the military spec because the products are more expensive to build.
But Mr. Shure was always a guy that saw long term. In retrospect, it was absolutely essential that we did that. And we still use military spec today far beyond what most of our competitors do.
Beacham: The SM57 has been on the podium of every U.S. president since Lyndon Johnson. Why is that?
Pettersen: If you go back and look at Eisenhower and even Kennedy, there was no consistent mic setup for the President. He would pretty much use whatever microphones were available at whatever location they went to. Sometimes that was good. Sometimes it was bad.
It was around the mid-60s when the White House Communications Agency was formed and they set-up microphone standards. The President always has to sound good. When the White House contacted us at Shure, they happened to talk to a guy named Lee Gunter, who worked here for over 50 years. He was a military guy during World War II and then was hired by Mr. Shure after the war ended. He knew how to deal with the federal government.
And he said, we’re going to help you and loan you some products to try out. We are going to give you an education in microphones. But we’re not going to give you any product, which was really brilliant, because if you gave things to them, it could be considered a bribe. We knew the SM57 would work well for sound reinforcement, because it’s twin sister, the 545, which was introduced in 1959, was being used for live rock and roll. The Beatles and the Rolling Stones were using it, and we knew it could be loud. The White House wanted that so the President could be heard above crowds. Even today, with President Biden, the White House has never had a failure of the SM57 mic.
Beacham: Is part of that because of the reliability of the dynamic element and the fact that it can handle a range of different environmental conditions?
Pettersen: That’s right. A dynamic element doesn’t care if it’s wet, or cold, or humid or hot. It handles all those conditions without any problems whatsoever. There’s something called meantime between failure. The SM57 has only about 40 parts inside and there’s very little to fail. So the simplicity makes it very, very reliable.
Beacham: The SM58, introduced in 1966, has become the musician’s microphone. How did that happen?
Pettersen: We had very little to do with it. In the 60s, the Beatles tried to play big arenas and the sound reinforcement systems were inadequate for it. So there were companies trying to figure out how to make systems which were much louder. One of the key events was the Monterey Pop Festival in 1967. A company called McCune Sound decided to mic up the entire stage with Shure SM56 mics, which were a predecessor to the SM58.
Monterey Pop is where The Who destroyed their instruments and where Jimi Hendrix lit his guitar on fire. The sound was so good that McCune started using the SM56s for all of their festival work on the West Coast. While this was going on, Shure was trying to sell the SM58 to radio and TV stations for interviews — the wrong market.
Then Woodstock came along, and Bill Hanley of Hanley Sound used the model 565, basically chrome versions of the SM58, along with Shure M67 mixers.
Eventually, the touring sound people started to switch over to SM58s. I would say in all honestly Shure didn’t realize that the SM58 was being used for rock and roll until sometime in the early 70s. Now it may be the best-selling mic in the world for musicians.
Beacham: You attempted to get Frank Sinatra to try a successor model to the SM58. What happened?
Pettersen: It was 1977, and Shure brought out the SM59. It looked different and sounded different from the SM58. I was 24-years-old and my boss told me to take the new SM59 to Las Vegas and show it to the sound engineers in the various venues. Frank Sinatra was at Caesars Palace rehearsing in the afternoon. I took the SM59 and showed it to Dave Rogers, the sound engineer at Caesars Palace. Sinatra was using an SM58 and Rogers asked Sinatra’s sound man if Frank would try the new mic. I’m in the sound booth when Sinatra comes out for the rehearsal. He looks at the SM59, which is not the mic he was expecting. He asks “where’s my f…. mic?” His sound engineer answered, “Oh Frank, this is a new mic from Shure. Would you mind trying it out?”
He’s not happy, but he kind of shrugged his shoulders. So he counts off the band for his first song, which was “Come Fly With Me.” He sang about eight bars, pulled the SM59 off the stand, and with all his might threw it hard, so that it bounced along the floor and hit the wall. He yelled, “Get me my microphone,” meaning the SM58. When Sinatra got his SM58 back, he was happy. After the rehearsal, Sinatra’s sound man returned the SM59 to me and said in a very quiet voice, “He didn’t like it.”
Beacham: Shure’s SM7 mic was introduced at the end of 1972. It was designed for radio, TV and recording studios. Then, in 2007, something extraordinary happened. The SM7B became popular for podcasting and gamers. Sales really took off. What is so special about that mic and why is it so widely used today outside of studios?
Pettersen: What a lot of people don’t realize is that the SM7B is basically a SM57 on steroids. It has a slightly enhanced low end.
Beacham: A lot of people feel that the SM7B’s low output makes it desirable in poor acoustical environments.
Pettersen: That is a factor. But it’s not the only factor. It also happens to have a really, really good cardioid pattern as well, which helps. It kind of limped along from 1972 to 2007 as a pretty successful voiceover microphone for radio and TV. And then podcasters got a hold of it. Sales really shot up. In 2015, gamers started using it. So now you have a mic that’s going to be 50 years old at the end of 2022 and we’re selling more of these things than we've ever sold.
When you compare the diaphragm of an SM7B to a condenser, it’s got a big, heavy voice coil of wire inside that weighs about 1000 times that of a condenser diaphragm. So it takes a lot more sound energy coming in to get it moving. When you work with the SM7B up close it works well. But sounds that are far away are so weak by the time they hit the mic’s elements, it becomes hard to get it to move. Having a heavier diaphragm assembly is actually to your advantage in this case.
Beacham: Thank you, Michael Pettersen!







