xMEMS announces Cowell, the world’s smallest MEMS speaker for TWS and hearing aid applications

xMEMS Labs today introduced Cowell, the world’s smallest monolithic MEMS µspeaker. At just 22mm3, 56 milligrams, and with a 3.4mm diameter side-firing package, Cowell delivers an impressive 110dB SPL at 1kHz. Cowell provides up to 15dB of gain above 1kHz for improved speech-in-noise performance and greater vocal and instrumental clarity versus electrodynamic and balanced armature µspeakers. Cowell is the first speaker to use xMEMS’ 2nd generation M2 speaker cell architecture offering improved SPL/mm2 enabling increased loudness in smaller form factors. Cowell engineering samples are available now, with mass production in early Q2 2022.

“Cowell’s architecture addresses two key hearables market trends: 1) spatial and lossless audio; and 2) over-the-counter (OTC) hearing aids,” said Mike Housholder, xMEMS VP of Marketing and Business Development. “Cowell’s small size and performance are perfectly aligned with these market trends with a fast mechanical response, up to 150x faster than incumbent speakers, near zero phase shift and +/-1 degree phase consistency enabling precise placement of audio in 3D space.”

For TWS applications, Cowell can be implemented as a full-range driver in occluded earbud architectures or as a small, high-performance tweeter paired with an electrodynamic woofer driver in non-occluded or leaky 2-way solutions. Cowell’s superior high frequency response delivers new levels of clarity and presence to speech, vocals and instrumentals, allowing the woofer to focus on low frequency energy required for active noise cancelation.

For hearing aid applications, Cowell is a full-range driver that is 45% smaller than an equivalent balanced armature receiver, making receiver-in-canal applications a possibility. Cowell’s superior high-frequency response, lack of in-band resonance peaks, and 15dB of gain above 1kHz make it an ideal speaker for addressing high-frequency hearing loss and improving speech intelligibility in noise. Lastly, Cowell’s speaker diaphragm is vented (front-to-back) enabling the relief of air pressure that may build-up over time inside the ear canal, resulting in reduced fatigue with increased long-term wear and listening comfort.

As with all xMEMS µspeakers, Cowell is a monolithic architecture implementing both actuation and diaphragm in silicon resulting in unmatched part-to-part frequency response consistency and reducing speaker matching or calibration time at manufacturing. This innovative transduction mechanism has also produced the worlds’ fastest and most precise µspeakers, eliminating spring and suspension recovery of coil speakers which improves audio quality and sound field reproduction. The side-firing package and 1mm-thin profile provides for placement flexibility in the earbud making space for larger batteries and additional sensor components. The SMT-ready package with an IP58 rating for dust/water simplifies system design, integration, and assembly.


Cowell samples and evaluation kits are available today for select customers, with mass production expected in Q2 2022. Cowell is available in a 3.2 x 1.15 x 6.0mm side-firing LGA package (3.4mm diameter). Cowell is paired with the xMEMS Aptos Class-H audio amplifier (1.92 x 1.92 x 0.6mm WLCSP).