Ed was born in 1910 in the small mining community of Eureka, Utah. Ed spent all of his childhood years there, only leaving to attend university in Salt Lake City. In 1927, Ed enrolled as a physics major at the University of Utah. Given the expenses of university and living away from home, Ed took a part time job as the night man at a local mortuary.
Ed came close to completing a degree, but did not graduate from the University of Utah. While in school, Ed continually moved up in position at the mortuary and decided to focus on his job for the time being. He ultimately stayed for the next 20 years. Eventually, he bought a 50% share of the company from his employer and became an equal partner in the business.
During this time in Salt Lake City, Ed pursued a hobby that would lead to a career change. This was his fascination of all aspects of music reproduction. He built home made tuners and amplifiers and was also active as a ham radio operator. He built his first loudspeaker in the late 1920's that consisted of a straight sided cone and field coil motor. This is remarkable considering that the first dynamic loudspeakers were invented in the mid 1920's.
Ed's son Rich recalls the massive system that comprised Ed's home audio system in the 1940's. The speakers consisted of a 2 x 2 multicellular horn driven by a Western Electric 594. Bass was reproduced by a Western Electric reflex enclosure containing an 18" bass driver. AM was the prime radio source and the tuner was a very modified Sparta bandpass TRF of very remarkable quality. His power amplifier consisted of push-pull WE 300B's with a UTC LS 58 output transformer. At this time, Ed was very active in the local Masonic temple, and this put him in touch with local radio producers, broadcasters and others in the audio industry.
In 1953, Ed decided that he had enough of the mortuary business. At the age of 43, he sold his funeral home and made a clean start in Dallas. Through his Masonic connections, he was able to get a job as a salesman for Muzak Corporation. While not particularly enamored of this work, he became interested in the business of the company that shared the building with Muzak. This was a small audio contractor, run by Jack Frazier, that was building public address systems and renting them out across the state for small fairs and public gatherings. Frazier also did a number of sound installations in the Dallas Ft. Worth area. One in Dallas was the Hotel Adolphus that incorporated a very early form of room equalization developed by Dr. C.P. Boner. The system was called 'ring mode equalization' where system gain was increased to feedback threshold and a notch filter tuned to this frequency was inserted in the signal path. Not many filters were used, but the results were impressive.
Ed and Jack got along well enough that they decided to become partners and formed the Frazier-May loudspeaker company. Frazier-May continued the development of professional sound equipment consisting mainly of bass and high frequency horns that were not dissimilar to the Altec Voice of the Theatre systems. They also made a successful effort to capture a portion of the burgeoning hi-fi market with home speakers such as the Dixielander.
During this time, Frazier May used OEM drivers, with Quam Nichols as their main supplier. Ed was always on the look out for better performing drivers and was very impressed with the JBL D208. He was developing a system that used a horn-loaded 8" driver and this JBL performed better than any previous transducer. Nonetheless, a fair amount of technical work was undertaken by Ed in getting optimum performance out of the D208. He worked closely with JBL in doing this optimization. In turn, JBL took note of Ed May's high level of technical ability. In 1956, JBL called with an offer for Ed to join the company.
Ed accepted and moved to California to work at JBL's new Casitas headquarters. He immediately became involved in all aspects loudspeaker engineering. Within three years, he would become JBL's primary transducer and systems engineer. He initially worked closely with Richard Ranger to develop the Paragon, Metregon and Minigon. He also worked closely with Bart Locanthi, who as a consultant, had been the primary technical resource at JBL since 1950. In 1960, Bart joined JBL full time as Corporate Vice President of Engineering. Ed became a Director, reporting to Bart, responsible for all new product development. In these capacities, Bart and Ed would work as a team for the next decade. Bart was the acknowledged theoretician while Ed was the practitioner that could take basic concepts and develop them into fully detailed products.
Their first collaboration was the development of the Linear Efficiency (LE) series of drivers. The name is somewhat meaningless and grew from the initials of the working name of the project – the Low Efficiency transducer project. The name was accurate in comparison to JBL's previous product lineup. However, it was considered corporate heresy to renounce the high efficiency that was so closely associated with the JBL name. Thus the name change to Linear Efficiency.
The LE series was developed in recognition that compromises in absolute accuracy had been made in previous JBL drivers to achieve maximum efficiency. The focus of this project was maximum accuracy and linearity, and thus there was a willingness to accept compromises in efficiency. Even so, the compromise was not that great. While less efficient than the classic JBL's, they were still more efficient than much of their competition.
Two of the LE series of drivers (LE15, LE8) pioneered the use of underhung voice coils at JBL. This motor topology ensured that the coils operated in a permanent magnetic field of constant strength, no mater what the excursion. Many of the bass drivers used Lansaplas coatings to lower the resonant frequency and extend low end response. Half-roll "Lansaloy" surrounds were developed for increased linearity at higher excursion and superior damping of the cone edge.
To many, and particularly according to his son Rich, one speaker of this series became the crowning achievement of Ed's career. That speaker was the LE8. It is a remarkable 8" driver that is practically full range, very linear within its bandwidth and capable of significant output. It truly is a universal driver and has found application as in home speakers, monitors, and more recently, high end auto installations. It remains in production to this day as the LE8T-H.
Another of Ed's innovations from this era was the 'passive radiator' or 'drone cone'. While discussed by Harry Olsen of RCA fame, JBL's use was the first commercial application. The driving force behind the development was the outdoor L57 loudspeaker. The enclosure could only remain environmentally sealed with the use of a passive radiator, while retaining the JBL reflex design. An additional product with a passive radiator was the Trimline 54 a very thin enclosure designed for wall mounting.
Ed May was responsible for all of the individual LE driver designs based on parameters set with Bart Locanthi. Ed was also involved with the design of the many systems that used these new drivers. The Olympus, the Apollo and the Lancer series were all designed to take advantage of the new LE series of drivers. Included in this new lineup was JBL's very first dedicated studio monitor - the D50SMS7. This was a 2-way monitor based on the new LE15A bass driver, LE85 compression driver and LX5 cross-over. It was JBL's first significant opening in the professional market, and would be fully capitalized upon with Ed's next major designs, the 4300 series monitors.
In 1968, Capitol Records had approached JBL for an update to the D50SMS7. This would become the renowned 4320. The power handling on the D50 was restricted by the low 500hz cross-over point. Integration between the drivers was also compromised by this cross-over. Ed designed the 4320 with a new 800hz cross-over that significantly increased power handling while providing both flat axial and power response. Where the D50 gave JBL a foot in the door in the studio market, the 4320 made JBL an established presence. Shortly after its introduction, the 4320 became Capitol's standard main monitor. For the first time there were also significant sales to record companies beyond Capitol.
Around the same time, Ed developed the compact 4310 monitor. This, and it's domestic conversion, the L100, would become the most successful loudspeakers yet produced by JBL. The 4310 was developed at the request of Bob Fine, an influential New York studio operator and engineer. Bob had just acquired a new Ampex 8-track recorder that was a significant advance on the previous, standard 3-track recorders. Bob's first thoughts in implementing this new technology was to have 8 studio monitors in the control room, or one speaker for each track. Using the industry standard Altec Lansing 604 Duplex would not work in this application since the enclosures for that driver were far too large to allow 8 in a control room. Therefore, Bob approached JBL to develop a monitor that had the same sonic signature of 604 but in a small package. The starting point was the two-way L88 that Ed had developed two years previous. It used a modified D123 called the 123A. It eliminated the duraluminum dustcap since it would not be needed in a two-way system and added a thick Aquaplas coating to extend the low frequency response. This driver was mated to the newly developed LE20 tweeter.
The sonic signature of the 604 was defined by a rising midrange response in the 2khz to 4khz range. Ed emulated this rising response a new midrange driver of his design called the LE-5. This made the 4310 into a three-way system that had good power handling, high output and a matching sonic character to the industry standard 604. The 4310 was an instant success. It small size fit perfectly with small independent studios that were beginning to take a larger role in the recording industry. It gave rise to the concept of nearfield monitoring that greatly mitigated room effects. While this monitor was in many ways Ed's most influential loudspeaker design at JBL, it would be his last for a number of years. In 1969, he was lured away by Cetec Gauss.
Cetec Gauss was a company known for magnetic tape recording technology. It had recently been purchased by MCA, and the new owners were looking to expand into different markets. In particular, they felt there was an opportunity for professional loudspeakers since the demand for musical instrument (MI) and studio transducers was growing at an exponential rate. Ed designed a complete range of loudspeakers including bass drivers, compression drivers and ring radiators. The MI bass drivers were unique in their use of twin spiders and heat sinks cast into the magnet structures. They gained a reputation for power handling and quality that kept them in production for nearly 30 years without changing the basic design. They were only discontinued in 1998.
JBL quickly recognized the loss caused by Ed May's departure and he was recruited back in 1972. He was first employed on the development of the Decade series. This was JBL's first foray into the mass market and became one of Ed's greatest challenges. There was JBL's longstanding reputation for quality to protect, juxtaposed with the desire to have product at a price point lower than anything previous. The resulting Decade series remarkably balanced these objectives to result in the most successful series of speakers yet produced by JBL.
Ed next turned his attention to more high end speakers. In the short space of two years, he turned out the L65 Jubal, L166 Horizon, and set the concept for the L212. The L212 was a groundbreaking speaker for JBL. In the past, JBL's design philosophy was based on the quality of its components. On this basis, JBL believed that system quality would be inherent. The L212 would be a departure from that tradition. The quality of that system would be defined by an overall systems engineering approach. It would include network tuning, time alignment and transducers specifically engineered for an overall system requirement.
Unfortunately, Ed would not have the opportunity to develop his concept into a production system. He left JBL in 1976, just as detailed design was just beginning. He joined Marantz Superscope to become their head of loudspeaker design. A custom design facility was built specifically for him. He used it to turn out three complete lines of loudspeakers in very short order. However, this was the last loudspeaker work he would perform. Edmond May passed away suddenly in 1980 while still employed at Marantz.
This profile opened with the assessment that Ed May was one of the most accomplished acoustic engineers of the past half century. This may seem to be overstating the case since the body of his published work is actually quite small. Nonetheless, the quality of his work, sheer output and influence in the industry speaks volumes. This is best exemplified by the quote at the end of this profile. It is by Bill Woodman, founder and senior designer for ATC Acoustic Engineers of Cotswold, England. ATC is one of the most respected manufacturers of high-end studio monitors and home speakers. Even though he never met Ed, here is what Bill had to say in a 2000 interview:
"The man who inspired me mostly, in truth, was Ed May, one of the very early designers at JBL. A lot of the thinking he incorporated, we've incorporated into our design. All one can hope to do is better engineer what is already known"
© 2003 Don McRitchie