Trumbull music lover gives wife the gift of stereo sound on the go

TRUMBULL — Daniel Glass has long loved music. 

The Trumbull resident began playing violin at 4, then bass guitar in middle school. When not playing, he listened to music — the enjoyment of which he would one day learn he was taking for granted. And that was a lesson that led to the creation of a device to better help those with unilateral deafness hear with more clarity. 

“It was only after I met my wife that I began thinking about how single-ear sound localization could benefit listeners with unilateral deafness,” Glass said. “I asked her what headphone setup she used when she listened to music, and she told me, ‘Just normal headphones.’" 

The realization made him think that there must be many people out there only hearing half of their music without even knowing it, he said.

“So, I made it my mission to try to help her and all those other people hear their music in as close as possible to the way most people can," he said.

Unilateral hearing loss occurs when a person loses the ability to hear most sounds in one ear. More than five million – including Glass’ wife, Mado – suffer from this auditory issue. 

And so, Glass — a licensed clinical psychologist by trade and founder of Yuni Technologies — put his creative skills to the test, inventing a device to help address this hearing issue: the Yuni V2. 

“I've also been a music lover and done a bit of recording and mixing,” Glass said, “So I'm very aware of the importance of stereo sound to the experience of modern music, gaming, and cinema.” 

Mado said when she was younger, she rarely told people that she was unilaterally deaf for fear of being perceived as different. 

“I once told someone, and the response was, ‘So, you can't really appreciate music.’ I was confused and upset, as I thought listening to music on my headphones from one ear couldn't be any different than anyone else,” Mado said. “I was wrong.” 

Upon meeting Glass and sharing with him her hearing limitations, Mado said he almost immediately started to think of what he could do to help her appreciate stereo sound. 

“Being a musician, he knew what would help,” she said. “I am now able to appreciate music while on the go, and in the way that the artist intended it to be heard."

She described the ability to hear music in stereo as "incredibly special."

The Yuni V2, which Glass said is the only single-sided stereo headphone on the market, is a Bluetooth headphone that allows listeners to hear 100 percent of their audio with a single ear in true stereo sound. This, he said, opens an entirely new dimension of their audio experience. 

“Since most modern audio recordings use stereo sound, which consists of left and right channels carrying two separate signals, listeners who are deaf in one ear are missing half of their audio when they listen through standard headphones,” Glass said. 

Current solutions involve collapsing the two stereo channels into a single channel, which is then played through one ear of a standard pair of headphones. But this approach, Glass said, causes the audio to lose its sense of space and depth. 

"The Yuni V2 resolves this problem by applying modern psychophysiology research into how the human ear localizes sound in vertical space,” he said. “By sending the two stereo channels to two speakers positioned above and below the ear canal in the same ear, the Yuni V2 leverages our natural ability to distinguish sounds from different elevations to bring the stereo effect to headphones for people with unilateral hearing loss.” 

Glass’ voyage into invention began when searching for a way for Mado to enjoy true stereo sound. 

“I searched for a product that could help her listen to true stereo sound, and the closest thing I found was a single-sided earbud that collapsed the stereo signal into a mono signal,” he said. “It was great that the company catered to this need, but the sound was a bit muddy and cramped because they were collapsing two channels into a single channel. There was no clarity or sense of space."

Such a solution also could create an awkward social situation because someone seeing her wearing a single earbud could then speak into her other ear, assuming she could hear them, he said.

So he took on the problem himself, he said.

“I consulted with a friend of mine who's a mechanical engineer who helped me write a patent,” he said about his initial startup in 2011. “My first proof of concept was a pair of Apple earbuds taped to a plastic Tupperware, and it was enough to convince me that a person can differentiate and localize two sound sources from a single ear."

The next prototype consisted of cheap earbuds glued to an existing headphone shell.

"And that worked well enough, too," he said. 

By 2013, Glass had commissioned a 3D-printed version of the Yuni from Chris Caswell, who now runs 3D Central, a 3D-print shop in Richmond, Va. 

“We ran a small but successful Kickstarter in 2013 to cover the cost of the prototype development, and it gave us enough seed funding to go into business selling individually hand-made Yunis,” said Glass, adding that the original version was priced at $80. 

It was through user feedback that, a decade later, he produced the Yuni V2. 

While many people loved the fresh 3D-printed look of the original Yuni, Glass said users said they wanted “the look, feel, fit, comfort, and sound quality of a factory-produced model. The new model, Glass said, meets the need. 

"Holding the factory prototype of the Yuni V2, and hearing clear single-sided stereo from a headphone that looked and felt like a retail product was overwhelming and felt like the culmination of over a decade of work,” Glass said. “I know we have a lot of work left to do before the dream is fulfilled of getting this product out there to the people who need it.”