Koss ESP/950 electrostatic stereophones Herb Reichert November 2016

Herb Reichert wrote about the Koss ESP/950s in November 2016 (Vol.39 No.11):

I was listening via Tidal to Jorma Kaukonen sing Mary Chapin Carpenter's intoxicating "Just Because," from his Blue Country Heart (CD, Columbia CK 86394). I was using the Pass Labs HPA-1 amplifier ($3500) and Audeze LCD-4 headphones ($3995). All I could think, as Jorma sang, Béla Fleck picked, Byron House plucked, and the sound was rousing and joyous, was What more should anyone want? Then Jorma sang the Delmore Brothers' "Blues Stay Away from Me," and I thought, This is genuine heaven. Life is not filled with tears and misery—it's filled with stunning guitar riffs and plucking-good attitude.

But the HPA-1 and LCD-4 aren't really "down home on the porch" like Jorma—they're kinda uptown, leisure-class expensive, and you guys know I'd rather make my own hooch than buy it. Then Jorma was singing "Red River Blues," and I'd switched to my new-old, always-enjoyable Koss ESP/950 headphones with matching E/90 Electrostatic Energizer power supply ($999.99, footnote 1). I was stunned by the richly textured midrange they delivered. Every note—every banjo pluck and guitar strum—was right there, "slippin' and slidin' up and down the banks." In his solo, House's bass moved like a Mississippi dam breaking—but not as loudly or powerfully.

The ESP/950s did not produce deep or voluminous bass. Compared to my Audeze LCD-Xes, the Kosses' bottom octaves were weak but well defined; the top octave seemed to fade a bit early (these are electrostatic headphones with plastic earcups, fer cripes' sake!), but oh my, what a glorious midrange! Always fresh and textured—"Wide open spaces all around me . . ." What more could anyone want?

I was getting high listening to Kaukonen sing Slim Smith's "Bread Line Blues"—I felt I was floating back to 1931. The ESP/950s' electrostatic reproduction was so effortless and tactile, I felt I could touch every word of the lyrics. The ESP/950 experience was so easy-flowing, it made other headphones sound as if they're straining to do their job.

"The latest news has struck me funny / Says you have no friends if you have no money." Then I listened to "Bread Line Blues" through the AudioQuest NightHawks ($599). The bass was stronger, but the song sounded muffled and distant. That's the usual sensation when you switch from fully open electrostatic to semi-open or closed-back dynamic 'phones. But I wasn't worried—I knew that my mind would soon adapt and the feeling would pass.

When I switched from the fully open-back, planar-magnetic Audeze LCD-Xes ($1699) or LCD-4s ($3995) or to the Koss ESP/950 electrostatics, it took a while for my mind to adjust to the reduced bass volume and lower treble energy. But that was okay. After a song or two, all I could hear were the plucking and strumming—and now the midrange textures were suddenly more perceptible because the bass and treble energies were reduced. I know, this was pure psychoacoustics, but several songs later, when I switched from the Koss electrostatics to the dynamic, pulp-coned NightHawks, my mind did not adjust—it wanted to stop listening. The excitement was gone. My soul really missed the Tesla-coil energy the electrostatics brought to the music.

"She walked into my life with her cold evil eyes . . . " Then I switched to John Cowan singing "She Darked the Sun," from John McEuen's Made in Brooklyn (24-bit/196kHz download, Chesky), which I believe is the most soulful, spine-tingling version of this Dillard & Clark classic. It sounded good through the NightHawks, but not as dark and twisted as I remember from the recording session (which I attended). When I switched from the NightHawks to my bunker reference 'phones, the Audeze LCD-Xes, transparency increased, the highs opened up, and the musical energy doubled—but I still couldn't find those dark, Hitchcockian underpinnings I'd experienced in the studio. Cowan's genius wasn't as present as I remembered. After a few more songs, I switched back to the Koss ESP/950s.

"Well, my memory cannot speak / and, Oh Lord, I'm feelin' weak . . . " Through the ESP/950s, Cowan was back—just as I remember hearing him in the former church in Greenpoint, Brooklyn, where Chesky recorded him. Of course, some bottom and top were missing, but a major chunk of Cowan's forceful vocal spirit was there, singing the best song lyric ever: "With the length of her mind she darked the sun." In the studio, I'd held back most of my tears as Cowan sang these words; now, I just let go and got totally wet-faced. What more could anyone want?

Introduced in 1990—Thomas J. Norton reviewed them in the December 1992 Stereophile, with a follow-up in February 1994—the Koss ESP/950s are still in production, still made in Milwaukee, Wisconsin. They're exceptionally light (10oz or 284gm) and comfortable, and come with a limited lifetime guarantee: If they break or wear out, just send them back to Koss; when they return, they'll be good as new.

Audeze's LCD-X and LCD-4 headphones are both of reference quality. Currently, the LCD-Xes are my benchmark for user-friendly balance of musical joy and accuracy. Nevertheless, there's more to life than bass and treble; there's happiness consciousness—and that's what the Koss ESP/950s delivered. (Remember, she-gods and their archangels inhabit the midrange!) To fully enjoy recorded music, we need to feel directly connected to the breathing, strumming, sad, happy humans who created it. I think the 26-year-old Koss ESP/950s still shine at making that basic human connection. They make music lively and intimate. I'm enjoying them completely, and I think some of you new-minted headphone enthusiasts might want to give them a try. I'm glad I did.

What more should anyone want?—Herb Reichert

Footnote 1: Koss Corporation, 4129 N. Port Washington Road, Milwaukee, WI 53212. Tel: (800) 872-5677, (414) 964-5000. Web: www.koss.com.
Koss Corporation
4129 N. Port Washington Ave.
Milwaukee, WI 53212
(414) 964-5000

ndimoff's picture

Another great news is that the electrostatic transducers of the Koss'es do not age. Bought my pair in April 1993 and they still sound as new. In comparison, the panels of my Martin Logan Aerius electrostatic speakers need to be replaced every 5-7 years.