The First MEMS Full-Range IEM

Singularity Industries, co-founded by Matthew Leanse and Nicholas Palomarez, made a bold bet on MEMS microspeaker technology. Their first design was the first in-ear phones to purely utilize a single monolithic silicon MEMS transducer. The bragging rights - and there is plenty to brag about - must be shared with the xMEMS (xMEMS Labs) acoustic team working together throughout the development of this compact and compelling product.

Over a bottle of wine, I sat down with Matt Leanse to hear about his R&D journey that led to the Paradox in-ear headphones. Before the first sip, he was already highlighting the challenges, motivations, and innovations behind developing one of the first in-ear monitors using Piezo-MEMS µSpeakers from xMEMS.

The Paradox in-ear headphones, the first with a monolithic silicon MEMS speaker, allowed for an incredibly miniaturized form factor.

Obviously, audio quality was the top priority. The unique strengths and characteristics of xMEMS’s Piezo-MEMS driver formed the foundation of this pursuit. Semiconductor uniformity, ruler-flat phase response, nearly non-existent group delay and amplifier-grade transient response to over two octaves beyond human hearing set these transducers apart. Matt often notes their quantitative and qualitative similarities to full-size electrostatic drivers, like those found in Stax Earspeakers, a north star reference point for Singularity’s in-ears.

These distinct qualities proved potent motivators to pursue the pot of gold at the end of the rainbow. Beyond the technical hurdles implicit in pioneering the implementation of a new and unusual transducer, Matt notes that his heterodox sourcing strategy implied its own array of advantages and challenges. Rather than using overseas contract manufacturing to simplify and expedite his supply chain, Matt insisted on sourcing and assembling the product in Silicon Valley, to the maximum extent possible.

For a speaker to reproduce bass with uncompromised accuracy, it must be capable of rapid excursion, unencumbered by air pressurization. To achieve this with a single MEMS driver in such a tiny enclosure, the Paradox mechanical design required a novel approach.

I commented that being the "first duck in the pond" requires enormous effort, including the subtleties of acoustic chamber design, EQ curve development, and not holding back low-end response with leaks or resistance. Each class of transducer needs its own secret design guidelines, and MEMS microspeakers, with their novel form factor, are no exception.

Then there are the difficulties implied by MEMS devices' unique appetite when it comes to amplification, as the unique opportunity for back EMF energy harvesting from capacitive transducers, such as the Montara Plus.

Read the complete piece now available online here