Miscellaneous

Art Dudley wrote about the Sopranino in November 2016, Vol.39 No.11):

In audio as elsewhere, there's nothing new under the sun (footnote 1). Thus, in their zeal to give consumers an ever-better facsimile of every note on their records, some audio designers turn their attention to old technologies. The California firm EnigmAcoustics, for example, has found a new use for something as old as the Earth itself: the electret, typified by such abundantly common minerals as quartz. And while EnigmAcoustics make their electrets out of exotic fluoropolymers rather than quartz, they have the same functional characteristic: electrets have an electric charge, which lasts virtually forever (footnote 2).

Fans of the electrostatic loudspeaker will perk up at that—still musing, as they surely do, over the engineering challenges overcome by the genre's greatest-ever designer, the late Peter J. Walker. The trickiest puzzle piece in Walker's development of the groundbreaking Quad ESL, nicknamed the ESL-57, was to devise a constant-charge diaphragm that could thus vibrate in reaction to the application, to the stators that straddle it, of a split-phase version of the music signal. But now—and here's where modern technology re-enters the story and is redeemed, Parsifal-like—EnigmAcoustics has succeeded in using a flexible electret, as thin as a monophonic LP groove is wide (25µm), as a diaphragm for a commercial electrostatic loudspeaker.

The product in question is the Sopranino (footnote 3), an accessory supertweeter reviewed by John Atkinson in the May 2014 Stereophile. For that review, JA paired the Sopranino with the Joseph Audio Perspective loudspeaker—a 36"-tall, two-way, three-driver floorstander ($12,999/pair)—and also with his vintage pair of Rogers LS3/5a minimonitors. With the latter in particular, JA enjoyed the tonal and, especially, spatial enhancements wrought by the EnigmAcoustics supertweeters, declaring that the Sopraninos "made a subtle but genuine improvement in the sound of my system."

Yet a question remained: How would the Sopranino fare with the Quad ESL itself? It seemed reasonable to hope the pairing would be heaven-made: After all, the relatively large size of the ESL's tweeter panel—26" high by 8" wide—creates what even the Quad faithful describe as an undesirable degree of treble "beaming," which in turn limits the size of the listening area from which a pair of the speakers can be heard at their best and keeps their overall treble extension notably modest. The points in the Sopranino's favor are many: at 4.75" by 3.5", the Sopranino's diaphragm is far smaller than the treble diaphragm of the Quad; that and the Sopranino's horn loading would seem to promise better high-frequency dispersion. Moreover, to the extent that any loudspeaker technology has its own characteristic sound, the electrostatic Sopranino might also be expected to blend seamlessly with the Quad.

And, perhaps best of all, the Sopranino's optional stand ($600/pair) appears to have been designed with the ESL in mind. These well-made, sturdy, aluminum stands allow the user to set the supertweeters at any of nine different heights, from 29" to 46" between the floor and the bottom of the tweeter, and one of those heights—32" above the floor—places the Sopranino so that its bottom just clears the top edge of the ESL, when the latter is used with its standard wooden feet. Not only that, but a dovetail notch at the front of the stand's baseplate perfectly accommodates the ESL's central, rear-mounted leg, allowing the user to scoot the Sopranino farther forward than would otherwise be the case. Neat.

A number of months ago, Quad ESL enthusiast Robin Wyatt, of the New Jersey–based distributor and retailer Robyatt Audio, loaned me his demo set of Sopraninos: two supertweeters and two stands, all of which had seen active duty at a few audio shows in the Northeast. Speakers and stands are supplied by EnigmAcoustics in excellent packaging—especially the speakers, which come in a padded wooden box all their own—but one of the tweeters of my review pair wasn't working. I kept the stands, returned the tweeters, and before long, EnigmAcoustics themselves had sent me a fresh pair of Sopraninos. I connected these in parallel with my well-worn Quads, using the jumper cables EnigmAcoustics supplies for that purpose. Of the three rotary-switch-selectable bottom frequencies for the Sopranino's high-pass filters—8, 10, and 12kHz—the 8dB setting gave the most pleasant and believable blending of highs and superhighs, particularly with voices and trumpets. Depending on the recording, I used the –0dB or –3dB setting of the two-position Gain switch, but relied more on –0dB.

After several weeks with the ESL-Sopranino pairing, I came away respecting but not quite loving the EnigmAcoustics' contribution to my system. Were I the sort of listener who places a greater emphasis on stereo imaging, I might feel differently: In my system and room, the Sopraninos made, by far, a greater improvement in spatial performance than any other aspect of playback. I heard the same effect with record after record, but it was seldom more notable than when I listened to the recording of Heinrich Schütz's Musikalische Exequien by Phillippe Herreweghe and La Chapelle Royale (CD, Harmonia Mundi HMC 901261). I focused my attention on the brief tenor solo that opens the piece: With the Sopranino added to the system, my response was similar to when I sit in my optometrist's chair and she switches her phoropter from a poor setting to one that's optimal—everything snapped into aural focus, so much so that the effect seldom failed to coax from me a surprised laugh. The difference was remarkable, the degree of spatial precision added by the supertweeter undeniable.

Especially with pop recordings made with generous use of overdubbing, adding the Sopraninos to the mix also offered a slight enhancement of subtle details of playing and singing. I have finally, after years of neglect preceded by years of overexposure, begun listening once again to the Beatles' Abbey Road (CD, 2009 remastering, EMI 3 82468 2), and I noticed that the addition of the Sopranino supertweeters made it slightly easier to hear John Lennon's piano work in those famous descending chords in the middle eight of "Something" (footnote 4). That said, for whatever reason, having the Sopraninos in the loop with my Quad ESLs, driven by my Croft Phono Integrated integrated amp, also resulted in an equally slight lessening of body, presence, and overall flesh and blood in the sounds of instruments and voices. With the supertweeters, every recording sounded more sharply focused and detailed, but also less corporeally there—and that's an aspect of playback that I'm at pains to maximize, always.

Notwithstanding the glitch in one speaker of my first pair, the Sopranino appears exceptionally well made, and its existence as the only electrostatic loudspeaker of my knowledge that doesn't require a bias supply—something that adds cost, complexity, unreliability, and even danger to any electrostatic panel—makes it all the more praiseworthy. But the Sopranino, while effective, seems aimed at a listener with priorities different from mine. At the end of the day, my assessment of the EnigmAcoustics supertweeter is precisely the same as JA's: "An audition will be mandatory prior to purchase."—Art Dudley

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Footnote 1: Stuck for an intro, I got out my credit card and leased this opening sentence from the good folks at www.audioreviewcliches.com. It was only slightly more expensive than "'My name's Art and I'm an audiophile.' 'Hi, Art.'"

Footnote 2: Defined, for our purposes, as 100 years or so.

Footnote 3: The EnigmAcoustics Sopranino costs $3690/pair, excluding stands. EnigmAcoustics, 11 Chrysler, Irvine, CA 92618. Tel: (949) 340-7590. Web: www.enigmacoustics.com.

Footnote 4: It's a tantalizing and somewhat frustrating hint: As can be heard on such bootlegs as Unsurpassed Masters Vol.5 (1969) (CD, Yellow Dog YD 005), Lennon's piano work in the rest of the song, which was omitted from the final mix—along with the coda that he seems to have kicked off—is both passionate and technically quite good.