The Glide: Spartanburg music teacher invents new instrument

Under the dim lights Saturday night at Georgia Tech's Ferst Center for the Arts, Keith Groover held his breath.

Groover knew his home-brewed music machine, The Glide, had been well-received by judges at this year's Guthman Musical Instrument Competition in Atlanta, but the Spartanburg-based inventor was up against strong entries from all over the world, including Australia, Chile, India and Italy.

He especially fretted over GeoShred, a digital instrument for tablets that has already won over music producers and journalists.

"It has something like 75,000 users, and I knew it was going to be the darling," Groover said. "So when they announced it had won second place, I just kind of closed my eyes."

That's the moment he realized The Glide was going to take home the competition's top honors. In less than a year, Groover had taken a simple idea — to build a music device around a person instead of forcing a person to conform to an instrument — and produced a functioning prototype using off-the-shelf components and programming skills he taught himself along the way.

The end result is a two-handed device featuring glowing buttons and a small joystick that looks like a video game controller. The Glide uses accelerometer sensors, tiny devices that measure acceleration, to clock the change in speed over time. Each controller has three sensors, which measure acceleration over multiple axes — in this case, X, Y and Z.

The combination of joystick, buttons and acceleration allow users to produce 48 different notes, with control over pitch, volume, rhythm, tone, glide and more.

It's about the person

"Most of the great musical instruments have one primary thing to manipulate," Groover said. "If you play the violin, you get really good at learning what makes a string vibrate and how to do that different ways. Trumpets manipulate a column of air. The primary variable you learn to mess with in The Glide is acceleration."

As a music teacher, Groover said traditional instruments like guitars are constructed for their ability to produce sound, but many are awkward to hold and awkward to use.

"They have a job to do, and that's not often user-friendly," Groover said.

Working from a blank slate, he said he tried to imagine an instrument that would be the opposite. He'd seen demonstrations in the past using accelerometers for air drums, but he didn't like the execution. A double-fisted design became his solution.

Getting it all to work

Groover said his instrument largely uses components anyone can buy these days, tech that would likely have been cost-prohibitive just 15 years ago.

Accelerometers are now ubiquitous in devices like smartphones. They allow you to tilt your screen to change its orientation, for instance.

He taught himself Arduino, a programming language first developed in 2003 that allows for an easy, cheap way to program simple circuits to manipulate devices like sensors.

"The physical hardware to assemble the first prototype was actually really simple," Groover said. "That took maybe a month. The majority of the process was in learning Arduino and how to get it to do what I needed."

With no programming background, Groover said he waded into the task armed only with a friend's advice and online tutorials. The device that won in Atlanta is only his second "finished" prototype, but the ability to reprogram the circuit allowed him to toy with different features — Groover estimates hundreds of times — to get it right.

He used the Spartanburg County Public Libraries' SPARK Space to print the cases for his designs.

What it's like to play

Currently, The Glide produces sound through applications via Bluetooth, but Groover said he hopes to be able to produce sound directly through the controllers in coming months.

He's the world's first Glide musician, so he said he's working on teaching the instrument to others.

"As a music teacher, one of the guiding principles is that you want a student to have a smooth learning curve," Groover said. "For this, I'm thinking about a beginner mode where you can kind of scale back the features. When you understand how to do the fingering and notes, then you can turn on the next features."

While Groover is the world's best Glide player right now, he said he expects that to change soon.

"One of my kids laughed and said somebody would be better in less than six months," Groover said. "And they're probably right. Adults nearly always have to think about skills they've learned later than, say, people in their mid-teens. Kids pick things up fast and just run with it. I'm hoping that's exactly what happens with this."

Groover expects to begin producing The Glide by this summer.