How many speaker drivers do earphones need to deliver great stereo sound? One in each earpiece? Two? Six? The Knowles Corporation has partnered with Ultimate Ears Pro for the release of the UE Premier in-ear monitors, which rock a frankly insane 21 drivers per earphone.

Initially shown at the 2023 NAMM Show at the Anaheim Convention Center in California in April, Ultimate Ears Pro’s “most powerful, nuanced and versatile in-ear monitors yet” are said to set a new gold standard for exceptional audio, and are now ready for gigging musicians, studio producers and demanding audiophiles alike.

The UE Premier IEMs are reported to be the first in the industry to sport 21 drivers per earpiece with a five-way passive crossover design, including eight Knowles dual-diaphragm balanced armature receivers for a “warm, natural sound” and four Knowles supertweeters that extend the upper end along with UE Pro’s True Tone Plus driver.

Ultimate Ears Pro/Knowles Corporation

“The dual-diaphragm and supertweeter receivers allow us to define a new dimension of sound, achieving the best possible frequency response and acoustic resonance for an airy, rich and versatile listening experience,” said UE Pro’s VP and General Manager, Philippe Depallens.

UE Pro says that each driver has been individually tuned for accurate reproduction of different frequency bands, getting down as far as 5 Hz and right up to 40 kHz. And to ensure a secure fit and optimum passive isolation, buyers will need to submit impressions created by an audiologist or obtain digital ear scans to enable UE Pro to precisely 3D print the custom shell to individual requirements.

The UE Premier in-ear monitors are available now in a bunch of colors for US$2,999.

Product page: UE Premier