A look inside the research and development approach that continues to deliver as the company celebrates its ninth decade.
By Keith Clark • February 13, 2018
At Electro-Voice, sound quality is paramount. It’s been that way across the company’s illustrious 90-year history, and has never been more so than today. The backbone of the effort is a world-class research and development team, which works in state-of-the-art facilities stocked with leading-edge tools at company headquarters in Burnsville, MN, just outside of Minneapolis.
“It all starts with the people, and what we seek from every member of our team is the right combination of solid, foundational engineering skills blended with creativity and passion,” explains director of engineering Bill Gelow, who’s led the department for more than 17 years following key roles with several top professional audio manufacturers.
The bedrock of the EV approach to product advancement is exuded by chief engineer Dave Carlson, who’s played an enormous role in the development of numerous game-changing (and patented) loudspeaker technologies over more than three decades with the company, working with great group of younger talent such as principal engineer Mike Kasten, who came aboard immediately after earning a degree at Michigan Tech.
“There’s a wealth of engineering talent in the younger generation, and that’s exemplified by Mike,” Gelow notes. “We learned of him via his involvement in an outstanding AES (Audio Engineering Society) chapter at Michigan Tech, and in fact, we’ve also brought onboard two more engineers from that deep talent pool, including a PhD mathematician who’s a speaker guy. It’s been a driving catalyst that spurs our development efforts to further heights. These are very knowledgeable individuals, of course, but the real difference-maker is that they also have a true passion for audio, technology and engineering.”
Kasten hit the ground running upon joining the department in 2006, focusing first on refining the digital signal processing (DSP) that works in tandem with many of the company’s loudspeakers, as well as refining data and measurement processes. “The goal was taking what we’d been doing, which was already quite good, and improving upon it with new and alternative approaches; in other words, taking things to the next level.”
He’s since transitioned to loudspeaker system design, including participating in the transducer development that’s key to the success of those systems. Over time the role has expanded to all facets of loudspeaker systems: “Everything from cabinets to rubber feet and everything in between,” he notes with a laugh.
Carlson, meanwhile, serves as the “glue” of the loudspeaker development program. Since joining the team in 1985, he’s contributed to countless systems, including Manifold Technology, X-Array and X-Line concert systems, and has mentored many new pro audio engineers along the way in step with these developments in system design.
Carlson too possesses the multi-discipline skill-set that’s a hallmark of the EV engineering team, beginning with a primary focus on large-scale sound reinforcement systems that continues to this day, along with transitioning to also working with transducers and horn design. “It’s a little bit of everything, contributing what I’ve learned as well as fostering the work of others,” he explains.
This is a main theme throughout the EV engineering group: a diverse set of engineers working side by side, sharing what they know with each other. With new engineers working alongside seasoned veterans on all EV engineering projects, it’s a rich learning environment, and sometimes it’s the veterans who learn from the younger team members.
While he’s already quite busy directing and staffing a dynamic, growing R&D effort, Gelow manages to stay engaged in hands-on activities as well. “I remain fascinated by compression drivers and waveguides, so that’s where I put my focus every chance I get,” he says. “There’s just something about generating tremendous high-frequency energy and then being able to focus and control it that really intrigues me as an engineer.”
He also points to the X-Line Advance X2 line array as a particular recent highlight and one that exemplifies the EV approach: “It’s a project that morphed over time into something that Dave, I, the transducers folks, and a couple of others really wanted to do, and then a whole lot of our team contributed valuable work in making it happen. It was a collaboration of dynamic talents, and the end result of that teamwork is something we’re all quite proud of.”
What defines the “EV Sound” that’s at the core of every product? In fact, it’s a question the organization asked itself several years ago, and the definition distilled down to two words: accurate and pure.
“Obviously, there’s a lot of explanation that go into those terms,” Gelow adds, “but what it boils down to is a process we apply to everything, no matter what it is.” The product development process often begins by looking for ways to further improve upon the most recent accomplishments of the team, all while keeping the core sonic attributes firmly in focus. “No matter the price-point, no matter the scale and size, making it sound good without a compromise to quality is the challenge.”
An example of how well this process can work is EV’s current market share in portable systems, with Carlson noting, “One big benefit is having people who’ve worked on high-end, high-performance products who share what they’ve learned for even the most price-sensitive, lower-cost products. That’s an advantage of our depth in terms of experience.” Gelow follows, “There’s very much an understanding that you don’t ever compromise the sound quality. You may have to make trade-offs such as compactness, or price, or power/output, but the sound quality must remain sacred.”
Electro-Voice designs all components in-house – enclosures, waveguides, drivers, amplifier modules, and DSP – a factor that helps ensure a cohesiveness and consistency in everything from stand-alone loudspeakers to networked systems. Additional constants of the process are an eye on complete transparency and linearity in the place it all starts with loudspeakers: the transducers. As a result, the need for external processing is minimized but, when DSP is used, it is highly focused to achieve optimum performance.
The genesis of every product is what the company calls a CRS (customer requirement specification) that defines every single attribute that’s important to customers. Once the CRS is set, it’s translated into the design specification, covering aspects ranging from class of transducers, power, DSP, enclosure type and size, and so on.
The transducer level is addressed first, and once that’s known, it’s on to other key factors. It’s a process marked by rigorous testing and measurement before, during and after development commences. “There are several very important aspects in measurement: understanding what to measure and why it’s important, the ability to make measurements and make them with high accuracy, and then understanding what all of this data is telling us in using it to inform and optimize the design,” Carlson says.
As a result, measurement methodology, transducers, and systems are a constant focus, with stepping stone improvements made along the way, plus two complete upgrades of processes, methodology and equipment in just the past decade.
In fact, the engineering group just completed the latest advances on the department’s two-axis rotator system, which facilitates high-resolution spatial measurement as well as three-dimensional mapping. The ability to rotate even large loudspeakers at two-degree resolution, which the company established more than 30 years ago, is rare in professional audio, and that capability has now been furthered in its third generation.
It’s the continuation of a 90-year-old engineering heritage that dates back to the company’s earliest days, when founders Al Kahn and Lou Burroughs set the pace with numerous pro audio firsts and patents, followed by a commitment to further the research of sound with one of the first anechoic chambers outside of a research laboratory. In fact, that original chamber still exists at the Burnsville facility, transferred from the company’s previous Buchanan, MI location under Carlson’s supervision.
Staffed by several engineers and support staff, EV’s well-equipped labs include power testing capabilities where voltage and current can be measured on more than 30 channels simultaneously. There are also complete acoustical, structural and magnetic modeling and simulation capabilities, with another highlight being a mechanical and structural testing facility centered around a 10-ton pull-test fixture.
“I built the first pull-test site in Buchanan in the mid-1980s with a capacity of 10,000 pounds, and we’ve since doubled the capacity to 20,000 pounds,” Carlson notes. “This is invaluable in developing the integrity of both rigging as well as the loudspeaker cabinets themselves. Of course, the effort all starts with serious math before moving along to the actual pull-testing. Everything needs to be as strong as it can be, and we must account for worst-case situations.”
The deep R&D team also includes members who excel in creating prototypes, there’s a complete machine shop on site to bring their creations to life. In addition, standing by are two 3-D printers that are very helpful in creating components and prototypes.
Yet another benefit comes from being located in the Minneapolis area, the home of leading technology companies such as 3M, Toro and several medical device developers. Companies like these support facilities for rapid prototyping, die-casting, additive manufacturing, and in general, fostering technologies for faster development with cutting-edge quality.
Getting back to transducers, EV’s lab (purpose-built by EV engineer Alan Babb) provides the ability to wind voice coils, magnetize magnets, develop motor structures and even manufacture transducers right on site. This is extremely helpful to the group dedicated to transducer design.
“Pretty much whatever anybody wants, if it’s possible, we can do onsite when it comes to transducers, accompanied by very sophisticated measurements capabilities,” Gelow says. “There’s a 3-D scanner that can deliver 3,000 measurement points from a diaphragm in motion, so we can investigate break-up modes and see a whole lot of additional relevant data and parameters that translate to performance.”
The application of the considerable benefits of laser technology is also a staple of the design and development process. Again, it’s a capability steeped in the company’s deep engineering heritage, dating all the way back to the early 1970s when EV pioneered the use of holographic interferometry (laser technology) to study the motion of microphone diaphragms.
Speaking of microphones, they remain integral to the EV Sound, supported by a tightly knit, dedicated group of specialized engineers outfitted with facilities mirroring those of their loudspeaker counterparts, including their own anechoic chamber. Under the direction of engineers Bob Eaton and John Rosenow, every detail is analyzed and optimized, from the diaphragm, to how to port the design for directivity control, down to the mechanical suspension to keep it quiet.
The result is a steady stream of innovation such as that delivered by the RE320, the company’s latest Variable-D design, which is equipped with a unique “Dual Personality” switch that creates two ideal mics in one: one position provides a lively yet natural tonal response for vocals, electric, and acoustic instruments; the other delivers a curve designed specifically for kick drums.
Another example is the ND Series of wired vocal and instrument mics, which debuted last year, incorporating even more advancements in neodymium technology that EV originated more than three decades ago. The result is new levels of sonic performance combined with innovative mechanical solutions that solve challenges that have plagued users for decades.
With both microphones and loudspeakers, double-blind listening is a significant part of the development process, evaluating the devices on their own merits and then comparing them with established and often much more expensive products to serve as a vital measuring stick.
Another important aspect is the R&D team’s increasing use of highly accurate acoustic simulations that assist in attaining the desired sonic performance before the critical double-blind listening evaluations. For example, the leading-edge COMSOL Multiphysics software platform proved crucial in refining the acoustical performance of the X-Line Advance Series of line arrays, and Infolytical is used to design high efficiency, low distortion motors for transducers.
“These tools deliver vital input, giving us a very good idea of performance at both a system level as well as in larger scale arrays,” Gelow explains. “They are highly accurate in terms of both the models and simulations, which translates into efficiency in helping us deliver designs that are right the first time.”
Prototypes of all but the largest loudspeaker systems can be deployed and evaluated on-site, including the ability to erect and even fly mid-size rigs. Again, the Twin Cities area provides advantages in this regard, with numerous live performance venues of all types available to serve as real-world test labs, including the Xcel Energy Center in downtown St. Paul that’s noted as providing one of the finest acoustical signatures of any large arena on North America. As a result, it facilitates a truly meaningful evaluation process.
Key customers also play a role in development and optimization, sought for their invaluable input on overall performance as well as factors such as fine-tuning DSP. For example, several sound companies were involved in refining the company’s FIR-Drive platform for the X-Line Advance Series. “The views and input of our users is absolutely vital,” Gelow states. “There are things you can’t do, even with big rigs in appropriate test conditions, which can be accomplished with the help and expertise of audio professionals working with the gear in real-world field conditions.”
The support of the support of parent company Bosch GmbH, itself an engineering-based organization, brings further benefits to the EV engineering table. “Bosch has a commitment to engineering, and that’s a company-wide commitment, which is a real plus,” Carlson notes. “They’ve been a good steward of Electro-Voice.”
Yet another asset comes courtesy of EV’s German sibling brand Dynacord, also Bosch-owned, which develops electronics in sync with EV loudspeaker designs, utilizing algorithms usually developed by the team in Burnsville that are perfectly in line with each product.
In addition, Dynacord recently debuted two new power amplifier series, the L Series (for live/portable) and the C Series (for installations). Both incorporate onboard DSP that includes multi-band parametric equalizers, crossovers, limiters, and delay per channel, as well as true channel grouping control with extra DSP capabilities like parametric EQ, graphic EQ and delay for each group.
While they have deep roots in the tradition of EV engineering and product development, both Gelow and Carlson have their eyes firmly on the future of the organization. “Dave and I are both very committed to passing along everything we know to the coming generations,” Gelow emphasizes. “We like what we do and the people we do it with, and together we continue to create technology that’s meaningful to our customers as well as to the world of sound reinforcement.”
Credit Keith Clark Editor In Chief, ProSoundWeb & Live Sound International