Musitronics—better known by the nickname Mu-tron—produced some of the best-sounding and best-made effects of the 1970s. They also produced the Dan Armstrong line of effects.

Today’s guitarists have nearly limitless choices when it comes to effects. However, 40 years ago the effects roadmap was still being drawn—designs we now take for granted hadn’t even been conceived. Mike Beigel of Musitronics—a company better known by its nickname, Mu-tron—was one of the effects pioneers whose decisions about the sonics, functionality, and appearance of effects would influence countless subsequent builders.

Throughout the 1970s, Mu-tron products were second to none in quality and innovation. Classic Beigel-conceived effects include Mu-tron’s dual-oscillator Bi-Phase and the Mu-tron Octave Divider, but the company also had a hand in the miniature effects marketed under the Dan Armstrong brand. The latter included the Orange Squeezer compressor and Green Ringer ring modulator, whose circuits inspired countless imitators. The most celebrated Musitronics effect is probably the Mu-tron III, the first envelope-controlled filter in modular form. It became one of Jerry Garcia’s signature sounds. Frank Zappa, Larry Coryell, and Bootsy Collins were also users, and Stevie Wonder used one for the quacking clavinet tone on “Higher Ground.”

However, great technical ideas can fall victim to poor economic decisions, making superior brands fall by the wayside while lesser ones prosper. Mike Beigel recently spoke to Premier Guitar about how a mechanical white whale destroyed his influential company—and how horses imbedded with RF chips may have helped fund his latest venture.

What were your first electronics projects? When I was a kid I used to take TV sets apart just to see what was in them. I got an electronics kit when I was 11. I made some science fair projects: a biofeedback sensor and a thermoelectric sensor. When I was 15 or 16, I started building hi-fi sets and learned to play guitar. Eventually, I had to decide whether to go to music or technology school. My parents advised me that technology school was a surer way to eat, so I chose MIT [Massachusetts Institute of Technology].

What years were you there? I got there in '64 to study electrical engineering. I got my second degree in 1970. They had a music department, but they had no knowledge whatsoever of electronic music. The first electronic piece I ever heard was Karlheinz Stockhausen's Gesang der Jünglinge. It made an awesome impression on me. Meanwhile, I got interested in philosophy, psychology, and art. Engineering wasn't enough for me, so I asked my advisor how could I combine engineering with the humanities. He said, “I don't know what to tell you.” Then, one rainy Saturday night in November of ’67, I was playing the clarinet and saxophone into the soundhole of a 12-string acoustic-electric. I turned my amp up and got an electroacoustic sympathetic string effect.

Like drone strings on a sitar? Yeah. We were all listening to Indian music a lot then. Ravi Shankar would come to MIT and give concerts. My third-year professor, Barry Blesser, was one of the guys who started digital audio. We had to do a project, and I asked if I could explore using an electro-acoustical model with strings, pickups, and a box to deliver sounds that would turn into sympathetic vibrations. That ultimately became my bachelor's thesis. I took a second degree in electronics and humanities, majoring in music. Meanwhile, my crazy buddies and I had a radio show, The Electric Chair, on the MIT radio station. We would do things like play five or six kinds of music at the same time, while talking about things you were vaguely not allowed to talk about. A high point came after a Mothers of Invention concert, when Frank Zappa and the band came and did an interview. Around then I decided that I really wanted to make electronic music my career.

So that’s when you built some of your first prototypes? Yes. One day a friend of mine was walking around Tech Square in an altered state, and he walked in on some people actually building a yellow submarine. He spoke with the project financier, and the next thing you know, we had formed a think tank of sorts. My friend was busy with school, so he made me president. The first thing I did was start building the machine I'd done my thesis about. Then I started building really weird synthesizers—more in the direction of Buchla than Moog. I ended up making this thing that looked like a four-key trumpet. Synths were monophonic at the time, but on this little thing you could play all the chromatic notes with different finger patterns, and with the other hand you could control parameters. One day the financier guy came in and said, "Look, the stock market's crashed. I've got no more money for you guys." The company folded, but a couple of months later we got a call from Guild guitars.

…one rainy Saturday night in November of ’67, I was playing the clarinet and saxophone into the soundhole of a 12-string acoustic-electric. I turned my amp up and got an electroacoustic sympathetic string effect.

So you developed the synth for Guild? Yes, Al Dronge from Guild ended up buying the project. I remember sitting in the Guild office in Hoboken [New Jersey], and [Grateful Dead guitarist] Bob Weir walked by! We started on the synthesizer with the strange hand-piece controller and the keyboard. But one spring morning, in the middle of production, we got a call saying Al had crashed his plane. The vice president—an accountant—terminated our project. The guy who built the amplifier line for Guild saw the writing on the wall for his division and decided we should form a company using the knowledge we had gained from the synthesizer project.

At first we were going to do a ring modulator, but decided it was a little too strange for the mainstream. We decided to do an envelope follower, using the side of the synthesizer we called the “timbre generator” and one of the four voltage-controlled filters. We put them together and made the Mu-tron III, which was at first called the Auto-Wah. We decided to name the company Musitronics, but an investor thought of the contraction Mu-tron. The “III” came about from my preference for the number three. They were sold at E.U. Wurlitzer in Boston. They sold well, so we made more. Then Stevie Wonder used one on “Higher Ground.” He came out to play some music with us and talk. He was a great, open-minded guy.

What about subsequent Mu-tron effects? We knew we couldn't have a one-product company. We wanted to make a phaser, because Maestro was doing well with theirs. I was ignorant, though, and actually made a bucket-brigade flanger. It was very elaborate and didn’t go into production—it had controls for everything. I still have it. We called it a “phase synthesizer.” Larry Coryell used it on one song of his Eleventh House record.

We did eventually make a phaser using a transconductance amplifier instead of FETs. It was great, but it had dynamic-range limitations and a little distortion. For the Mu-tron III, we'd tried out all kinds of filter configurations, but the electro-optical thing just sounded best. We tried applying that to phase shifters. We developed the Bi-Phase, a dual phaser that you could sync and use in a lot of different ways. It had a lot of knobs and was way too big, but at that time big was considered good.

Probably because people didn’t use as many effects then, so space wasn’t such a concern. That's true. People rarely had effects boards then.