The first over-ear headphones with solid-state micro speakers are almost here, AMPACS said Tuesday. It noted reference-design prototypes with xMEMS solid-state micro speakers are now available. That brings us one big step closer to headphone makers putting it in their new headphones. That could start after the production version of the design becomes available to them in September. Before now, the new micro speakers were limited to earbuds.
xMEMS Labs’ patented 2-way module architecture uses solid-state micro speakers for mids and highs and a dynamic driver for bass. It improves spatial audio accuracy and reduces weight for gamers compared to conventional single-driver cans, AMPACS said. The new reference design is a cost-effective advance that could figure into multiple audio brands’ headphones.
Ahead of the latest news, Cult of Mac conducted an interview with folks behind the development from xMEMS Labs in May. After all, you have to wonder if some future AirPods Max or Beats cans might incorporate the technology (for the record, xMEMS told Cult of Mac it’s open to working with all partners, but confirmed none).
Ampacs and xMEMS Labs partner on over-ear headphones with solid-state micro speakers and dynamic drivers
So essentially, electroacoustic product design company AMPACS and micro electromechanical systems (MEMS) semiconductor pioneer xMEMS Labs moved forward Tuesday toward over-ear headphones with solid-state micro speakers that you can actually buy, like you can with earbuds. But what they’re talking about is a 2-way reference design, currently only in prototypes. Fortunately, though, headphones makers can buy and use it in their products as of September. If a bunch of companies buy the 2-way architecture, we could see a variety of new cans with the technology soon after that. But there’s no telling when or if Apple products might be among them.
“As a global leader in headphone ODM designs, AMPACS is uniquely positioned to bring xMEMS’ industry-changing innovations to audio brands and manufacturers throughout the world,” said James Hsu, vice chairman of AMPACS. “Leveraging our robust research and development team and advanced production technology, we’ve designed and integrated a truly disruptive solution that sounds better and costs less than single-driver headphones on the market today.”
Here’s how AMPACS describes the upcoming design release, which uses an “ultrasonic” Cowell micro speaker Cult of Mac wrote about in November 2023:
The design leverages xMEMS’ Cowell, the world’s smallest solid-state micro speaker, for precisely rendered highs and mids, and AMPACS’ dynamic driver providing deep, satisfying bass. The result is a ready-made, modular solution that headphone manufacturers can plug into virtually any headphone design, including open-back, closed-back, wired, and wireless, for next-level gaming and music listening experiences.
The journey from earbuds to big ear cups in headphones
Photo: Ampacs
During a call I had in May with xMEMS’ VP of Marketing and Business Development Mike Housholder and others, they spoke of the whole process of developing the new technology leading up to the AMPACS announcement.
‘You know, [we] internally at xMEMS were always questioning whether a technology that was designed for earbuds would really have enough power and influence and capability to really perform well in a bigger ear cup,” Housholder told Cult of Mac. “So we were almost in denial internally that we just didn’t think that the speakers we had at the moment were really appropriate for for this category.”
But then xMEMS folks met an engineer from audio company Turtle Beach, Neal Breitbarth. He soon came over to xMEMS Labs as director of Audio Applications. “He is is 100% responsible for us making progress on this technology,” Housholder said.
The potential for synced stereo phasing and fast impulse response Breitbarth found in xMEMS prototypes excited him, especially for applications like eliminating lag and fine-tuning 3D audio for gaming.
“It’s kind of like a light switch. It’s on it’s off,” he said. “If I have a light switch that can turn on and off versus a dimmer that I’m turning down and turning up to get my light on and off — that’s the difference between what’s going on with the xMEMS part versus what’s going on with a dynamic driver.”
Soon enough, Breitbarth’s experimentation paid off. He said the current prototype result adds greatly to what you get from listening to a dynamic driver by itself:
It made it so that I could actually create a headphone that sounds much more like speakers than what had been done in the past on it. That was something that it was like an ‘aha’ moment where I’m like, oh, wait a minute. This is really, really nice code. And when you turn our part on, we do a demo where you can listen to the low-end driver and it’s working through the crossover. You’re still gonna hear vocals and stuff. But as soon as you turn [our] part on, all of a sudden, you get this full image of left and right. And it’s kind of shocking and especially if you’re listening to bells and percussion, things like that. All of a sudden, it has full width to it that you weren’t hearing before when you were just using a dynamic speaker by itself.
Great for spatial audio headphones
And the new reference design should be especially good for spatial audio, Housholder and Breitbarth said. xMEMS developed the 2-way headphone concept “to provide audio brands with a wider soundstage for spatial audio with improved sound clarity and detail while also providing a faster time-to-market solution that reduces production costs,” according to press materials.
“Our collaboration with AMPACS is driven by our firm belief that solid-state MEMS speakers will redefine all forms of personal audio,” Housholder said. “And in creating this 2-way design, we’re moving the headphone market one step closer to a solid-state future. We encourage all interested brands to contact AMPACS so they can immediately begin producing headphones quicker and more affordably, while ensuring their products are lighter and better sounding than anything currently available.”
Better sound separation
Advances in driver design plus a decent amount of space inside speaker enclosures long allowed bookshelf speaker makers to separate highs and mids from bass to deliver a clearer, more detailed listening experience. But even the most advanced single-driver headphones can’t do that. And that’s where the Cowell micro speaker comes in.
Fabricated as a single piece of silicon, xMEMS Cowell serves as a miniature midrange-tweeter in the 2-way headphone design, providing great clarity and detail. And a 40-millimeter dynamic driver from AMPACS reproduces the low end.
According to AMPACS and xMEMS Labs, headphone manufacturers will realize serious benefits from using the design:
- Improved mid- and high-end frequency reproduction for cleaner vocals and spatial imaging.
- Lighter weight for improved wearing comfort.
- And much simpler back-volume acoustic design for faster time to market.
Design might actually cut costs and speed up product cycles
Photo: Ampacs
Plus, despite including the latest solid-state technology, the design won’t increase costs. Recently, more headphones makers have sought to reduce breakup effects of hard-driven speakers and boost clarity by using exotic dynamic driver diaphragm materials like graphene and carbon fiber. So replacing all that with this simple 2-way system can actually cut costs, the companies said.
“One of the benefits of of our speaker is we’re using silicone as our speaker diaphragm,” Housholder noted. “Silicone has a material stiffness on the order of some of these more exotic materials, about 95 times more stiff and rigid than paper and plastic that you commonly see in headphone speakers.” And it eliminates the expense and production difficulties graphene presents, he added.
The simple 2-way design with a silicone driver can also increase companies’ time to market, Breitbarth emphasized. As he found in his work gutting various headphones, he could swap in the xMEMS module, replacing an expensive graphene driver in less than a couple of days, including programming time. So it can vastly reduce materials and labor that goes into acoustical upgrades to traditional headphones, which might also result in faster cycles between major upgrades, as opposed to just cosmetic ones like new colors.
“So it really does make a big difference in the big picture of time to market and being able to swap out and change with whatever is current at that point,” he said. “You don’t have to have a year and a half development cycle to create your headphones. So that’s another big win.”
Read more about xMEMS Labs solid-state micro speakers:
- Coming ‘ultrasonic’ revolution could change wireless earbuds forever
- xMEMS Labs drives faster adoption of solid-state micro speakers for earbuds
- Noble’s swanky new earbuds use xMEMS’ advanced solid-state driver
Source: AMPACS and xMEMS Labs
