What if a silicon computer chip could produce sound? That’s the idea behind xMEMS’ Sycamore, a full-range, open-air, solid-state speaker driver that aims to revolutionize headphones, smart glasses, and other wearable devices.
Magnetic speaker drivers—which we’ll call “conventional speaker drivers”—have remained largely unchanged over the past century. They’re pretty simple, too: a copper voice coil is manipulated by an electrical current to vibrate a diaphragm and produce sound.
There are some constraints to this conventional design. Magnetic drivers are, at minimum, about 3mm thick. And size is a huge obstacle when building small form factor electronics, such as headphones, smartwatches, and smart glasses. Just look at Meta’s transparent Ray-Ban smart glasses. Its kidney-shaped drivers, located in each arm, take up a ton of space.
The xMEMS solid-state driver design follows some conventional rules. There’s a moving diaphragm, for example. But solid-state drivers are cast to a silicon die and take up far less space than an old coil and cone. They look similar to accelerometers and other MEMS-manufactured silicon components. They’re effectively computer chips.
I first learned about this technology when xMEMS introduced the Cypress solid-state driver in 2023. And although the Cypress was impressive, it wasn’t an open-air speaker and didn’t find much use outside of earbuds. This problem is rectified in the new Sycamore driver, which is designed for open-air applications.
The xMEMS Sycamore is just 1mm thick and 9mm tall. It’s about one-seventh the size of a conventional driver, and it only weighs 150 milligrams. I haven’t tested Sycamore and can’t attest to its sound quality, but xMEMS promises full-frequency performance comparable to that of a conventional speaker. In fact, the company claims that Sycamore will outperform old-fashioned full-range speakers at frequencies above 5KHz; great for voices, notification tones, and music with a lot of treble detail. (For this reason, headphone manufacturers may use the Sycamore as a tweeter alongside a conventional full-range driver. Earbud brands like Creative did something similar with the xMEMS Cypress.)
Even if the sound quality falls short of expectations, Sycamore could be an asset to wearable manufactures who are desperate to build comfortable, stylish, ultra-portable products. I should also clarify that Sycamore boasts an IP58 dust and swim-resistance rating; it’s fine for sports.
Sycamore-equipped wearables should arrive at the tail end of 2025 or the beginning of 2026. xMEMS plans to show manufacturing samples to journalists and business customers through the first months of 2025, with mass production beginning in October of that year. I hope to get a hands-on during the sampling period, and I’ll report on the experience if things work out.
Source: xMEMS
