Mic Check: How Vesper’s Revolutionary Microphones Allow Voice Interfaces to Exist Nearly Everywhere

Marion Desmazieres Jun 12, 2020
Alexa Voice Service Inspiration Spotlight Alexa Fund

Vesper is building next-generation microphones for smartphones and connected devices, revolutionizing technology that has not seen significant innovation in more than a century.

The architectural and material principles of many microphones used today have remained largely unchanged since Alexander Graham Bell patented the first device in 1876. Today’s most commonly-used technology is the condenser microphone, which traps air between a thin membrane and solid metal plate, reacting to distance between the two surfaces.

There are significant downsides to this method of audio capture: condenser microphones are highly susceptible to water, oil, dust, and particle contaminants – thus limiting the environments in which they can be used. They also require a constant power source in order to operate.

That’s where Boston-based company Vesper saw an opportunity, pioneering a new form factor for microphones that can operate in nearly any conditions where sound is possible. It’s not simply their environmental flexibility that makes Vesper’s microphones so powerful, but also their ability to generate electrical charge when bent or stressed, known as piezoelectric force.

Harvesting energy from the vibrations of the voice itself, these devices require minimal electrical input in order to operate. As a result, Vesper’s microphones – and the voice and sound devices in which they operate – can be freed from a wall socket or power input, offering vast new possibilities for smart devices and voice interfaces. 

The Scales Are Lifted

Vesper’s CEO Matt Crowley began working with piezoelectric devices in 2007, when the field was in its infancy. In 2014, he partnered with Bobby Littrell, who was developing piezoelectric microphones for possible use by NASA and DARPA (the Defense Advanced Research Projects Agency, responsible for developing new military technologies).

“NASA was using microphone arrays outdoors to monitor airplanes,” Crowley said, “but they had to bring all the microphones indoors every night because if you left them outside, any kind of adverse weather would break them. At the same time DARPA was pushing the idea of event-driven sensors, devices that will turn off and on automatically in response to the environment, so our low-power listening devices that weren’t sensitive to the weather seemed like a perfect fit.”

Initially, Vesper intended their devices for use in highly technical environments that would require bleeding edge innovations. However, with the emergence of voice interfaces and ambient computing on a consumer scale, Vesper’s use cases immediately expanded from the rarefied world of research and development to everyday use. “It wasn’t long after we secured our seed funding that the Amazon Echo was launched,” Crowley said. “Suddenly voice just started taking off, and it completely changed the direction of our business.”

The applications and form factors that Vesper’s piezoelectric microphones could enable made them a perfect fit for voice. “You don't have to worry if the system is going to be left indoors or outdoors… or if it's going to be exposed to dirt or smoke,” Crowley explained. “And then because it’s battery powered, I can have portable voice systems. I can put a little voice pod in every room.”

But with newfound opportunities came new challenges – specifically the ability to scale manufacturing to fabricate tens of millions of low-cost units every month, rather than a few hundred, as they had initially envisioned. Beginning in 2014, the Vesper team started work with semiconductor foundries and technology fabricators to develop a fabrication process that could allow them to scale up. They also developed a unique acoustic testing process for each of the microphones they ship, in order to improve quality assurance.

Working with the Alexa Fund

The Vesper team already knew some of the engineers at Amazon, and when they learned about the launch of the Alexa Fund they asked for an introduction. Vesper was among the Alexa Fund’s earliest investments in December 2016.

Many of Vesper’s current partnerships were facilitated by the Alexa Fund’s portfolio development team, which helped advocate for Vesper by facilitating introductions with various businesses within Amazon.

“A lot of the projects that will be available to customers later this year or next were facilitated by the Alexa Fund team,” Crowley said. “For example, within Amazon, the Alexa Fund introduces us to business teams, so that when they’re generating ideas for new products, they’re aware of the capabilities we may be able to bring. Someone might say, ‘this product would be great if it was battery powered, but we can’t do it,’ someone from the Alexa Fund will say, ‘Wait a minute. There is a technology you might want to look at.’”

Among the third-party devices where Vesper’s microphones can be found today are simplehuman’s voice-operated garbage cans. Linkplay has also integrated Vesper microphones into their audio modules and integration boards. 

The Future is Sound

While Crowley and his team can’t disclose precisely what they’re working on, there are entirely new product lines on the near-term horizon for Vesper. The team is also developing sophisticated signal processing techniques to separate unwanted ambient noise from a speaker’s voice, allowing for the use of microphones in adverse conditions.

As a member of the Voice Interoperability Initiative, Vesper is also working to ensure that voice-enabled devices promote customer choice, allowing the user to choose their preferred voice service through multiple, simultaneous wake words.

“The emergence of voice, and all these new voice-powered devices, has been critical to the success of our company,” Crowley said. “And there’s such a huge diversity of devices and possibilities – not only are we working with a company to make a voice-powered garbage can, but we’re also working with biotech and medical device companies, agricultural operations, and home safety devices. And there’s a lot of growth ahead.”

Learn More