Shure KSE1500 Electrostatic Earphone Review

‘Electrostatic Valhalla In Your Ears’

The review team here at headphone.com has seen and heard a lot of great headphones in our 25 years in business. So it takes a bit of something extra to galvanize us wholeheartedly on a product. Although its not completely perfect and rather painfully pricey, we all agree the Shure KSE1500 electrostatic in-ear system is a scientific landmark and a breakthrough headphone.

Yeah, we know we’ve been saying the ‘B’ word a lot lately, but it's a genuine testament to the maturation of the high-end headphone industry that every other time we turn around, there are new awesome headphones revolutionizing our sport. Whether it's big full-size planar magnetic cans or small in-ears or even portable ultra high-resolution headphone amp/DACs, the past couple of years have witnessed the audiophile headphone market take a quantum leap forward in cutting edge product development. The resulting dramatic advancements in sound quality has been some pretty heady stuff (pun intended). Seriously, it’s really a fantastic time to be into headphones.

The Shure KSE1500 electrostatic in-ear headphones certainly qualify as one of those revolutionary new products. Obviously, it's the first technological achievement of its kind and extremely expensive as is any early leading-edge design. But once we get over the hard wallet pounding, the thing that remains is how effortlessly the Shure KSE1500 makes our music drive us forward through a hard workday or survive that absurdly long plane flight with what seems to be only screaming babies aboard. The KSE1500 transports you deep inside the sound of the music with an energy and a clear precision few other in-ears can manage. In the end, it’s really the music and the musicians that we're all about here at headphone.com, so anything that brings us closer to the heart of the creative artist is manna to our ears. The Shure KSE1500 electrostatic in-ears may get nearer to that spiritual musical wellspring than any other in-ear headphone we have experienced so far.

To cover some quick technical background, electrostatic technology offers the fastest, most accurate transient response with the lowest distortion possible in speakers and big headphones but, until now, it had never been applied to in-ear earphones. The Shure KSE1500 in-ear system achieves a mind-boggling feat of audio engineering - delicately sandwich a lighter-than-air, vanishingly thin film membrane between two tiny back plates that are electrically charged to apply voltage variations across the membrane, thereby creating magnificent sound. Since air is actually much heavier than the microscopically thin film membrane itself, its own virtual weightlessness inherently dampens any acoustic resonances and allows a completely uncolored, accurate audio reproduction that is strictly faithful to the original source. In this design, a precisely linear ‘push-pull’ action occurs across the entire diaphragm with the driver force being radiated evenly across the whole surface which helps avoids any potential distortion artifacts. Certainly, the miniaturization of such complex acoustic componentry into a small, comfortable in-ear headphone is nothing if not a massive scientific breakthrough. But perhaps the biggest breakthrough is the breathtaking level of detail resolution, dynamic range quickness and incredible transient response speed the little Shure KSE1500 in-ear electrostatic system can conjure up.

Compared to a custom-molded Ultimate Ears Ue11Pro IEM, the Shure KSE1500 offered vastly better instrumental separation and detail in the midranges and highs. Especially throughout the upper midranges, the KSE1500 has a much sweeter, significantly more cohesive sound probably due in part to the cascading multiple-driver arrays employed within the UE11Pro quad-balanced armature that can sometimes betray the transitional crossover seams in the presentation. The 11Pro also lacked the open sense of air and quick extension at the top of range delivered by the Shure. Vocals almost appeared somewhat recessed with the UE11Pro while the Shure delivered an exquisitely unblemished midrange tone that made voices feel solid, centered and full of emotional body. Of course, excellent bottom-end response is among the chief attractions of the UE11Pro in-ear headphone and it clearly bested the Shure KSE1500 in both bass texture and low-end heft, although the UE also exhibited a slightly muddy sound way down below that was completely avoided by the fully resolved but less extended Shure KSE1500. Dynamics and overall clarity also went to the Shure, although we must sheepishly add that the always ephemeral musical ‘fun factor’ was seemingly more evident in the UE11Pro's whiplash sound versus the slightly astringent, drier approach of the KSE. Undoubtedly, the KSE1500 has a neutrality that is highly involving simply due to its sheer transparency, but it can also feel a bit rigorous and ascetic at times for listeners seeking heated slam and warm punch. Clearly, the electrostatic approach favors big detail over big impact. Judicious use of the KSE1500’s onboard tone-shaping EQ parameters can likely help address some of these audiophile quibbles.

Listening to straight-forward,  simply layered dynamic recordings like the Boogaloo Joe Jones ‘Right On Brother’ 1970 LP on Prestige Records, the fast energetic presence of the Shure KSE1500 allowed his classic 1950’s Gibson hollow body guitar tone to show a glowing, facile single-string attack that reveled in dexterity and smooth melodic soul-jazz inventiveness. By contrast, the UE11Pro showcased the funky second-line drive of  Bernard ‘Pretty’ Purdie’s bass drum against the sinewy guitar figures while downplaying the bee-sting welt of Jones's Fender Twin amp sound. With more complex, busy recordings like the UK pressing of the first Henry Cow ‘Legend’ LP on the Virgin Records label from 1973, the Shure KSE1500 sounds collected and composed with a cool, easy pacing that made the angular music appear more accessible and democratic. The UE11Pro had obvious difficulties keeping up with the obtuse frenzy and smeared much of the high-tension interplay between Fred Frith’s skronk guitar and the chattering saxophones of Geoff Leigh and Tim Hodgkinson, leaving an unresolved miasma of broken-sounding notes in its wake.

For audiophiles needing the best of the best for mobile or portable listening, the Shure KSE1500 will likely blow away any balanced armature or dynamic driver in-ear headphone in terms of  resolution and midrange/treble openness. It has confessional, revealing sound quality that shines a bright white light into favorite recordings and lets you hear them in a precious new way. Of course, its not a product for everyone. It is indeed prohibitively expensive and big bass lovers or seekers of blanketing tonal warmth may not find themselves well-served here, although the aforementioned onboard parametric EQ feature does allow for some personalized tweaking of its energetically direct, zero-hype/zero-bloat style. It’s also plainly obvious that using only lossless quality audio files is demanded. Even with the Shure KSE1500 high-caliber digital processing abilities, low-res streaming music heard through reference electrostatic headphones will still sound like 360p videos look on a giant 4K-resolution HD television - it can be done, but the results sure ain't going to be pretty.