Analog Corner

With its swept-wing shape and platter-forward design, Sperling-Audio's L-1 turntable ($35,950, without tonearm; footnote 1) stands out in a crowd. This high-mass design from Germany is the result of a collaboration between Ansgar Sperling and Michael Bönninghoff, two fiftysomething engineers who began working together in recording studio construction.

Both also bring to the L-1's design and construction years of experience in signal processing. For years, Bönninghoff was the chief developer at Brauner microphones, and today is the technical director of the German pro-audio company S.E.A. Sperling worked in radio and signal processing, and has a strong interest in tubed electronics.

The Sperling's Design
The L-1's massive aluminum-alloy platter alone weighs 60lb; the entire turntable assembly weighs about 110lb. The massive bearing assembly bolts to the lower aluminum V-shaped wing, which sits on three massive, adjustable feet of machined aluminum, the central one directly below and coupled to the platter's bearing assembly, where it acts as an energy drain. The points of the feet sit in nicely machined and plated dimpled discs.

The two halves of the "V," each topped by a mounting plate for a tonearm, are of sandwich construction: three plates of aluminum alternating with slabs of a variety of materials, all five layers secured together with four beefy M8×90 bolts. The sandwich fillings can be of polyoxymethylene (POM), acrylic, slate, or wood, depending on the customer's preference—the tuning-obsessed can, with little difficulty, swap them out and compare their sounds.

The L-1's most obvious innovation is the armboard's mounting plate, which looks like something filched from an observatory. It consists of a pair of eccentrically arranged circular plates, each of which can be rotated, then locked down with machine screws that fit into slots around the plate's periphery. Drilling the arm-mounting hole off-center in the inner of the two circular plates allows for an even wider range of adjustment of the tonearm's pivot-to-spindle distance.

A removable, crescent-shaped insert next to the circular plates can be swapped out with the plates to provide enough pivot-to-spindle distance for 12" and even longer arms. While this requires a lot of screwing and unscrewing, it also provides unparalleled flexibility of positioning. By noting the numbers and letters silkscreened on and around the various plates, you can easily swap out multiple arms without having to remeasure and readjust pivot-to-spindle distances.

The M-2 motor housing is also large and massive, and rests on three conical, height-adjustable aluminum feet sitting in dimpled discs. UK-based Trident Engineering provides the low-voltage DC motor, which is driven by the outboard, zero-feedback NRM-1/S motor controller. At the 2013 Munich High-End Show, Ansgar Sperling told me that the famous German optics company Carl Zeiss AG manufactures the high-precision motor pulley and does all of the plating.

The platter is driven by an inflexible Mylar tape that resembles the clear leader of reel-to-reel audio tape. Sperling provides a few variants that it claims alter the sound. To make it easier to use and adjust tension, the motor is secured in a movable platform inside the M-2, with its distance from the platter adjustable via a system of dials for coarse and fine tunings.

Setup and Use
For $35,950, you're entitled to but don't always get the level of quality of L-1's exquisite machining and plating—which also goes for the Sperling's wheeled road case, one of the biggest and most attractive I've seen. To review turntables, I use a large Harmonic Resolution Systems base; I adjusted its six feet for the L-1's high mass, and I and Gideon Schwartz, of Sperling's US distributor, Audio Arts, hoisted the L-1 onto the base. That was the easy part.

Then we assembled the substantial inverted-ball bearing system. Next to that of my Continuum Audio Labs Caliburn turntable, which I've seen only in photos, the L-1's bearing system is the beefiest I've seen on a turntable, and consists of a large-diameter spindle integrated into the oil reservoir, the latter bolted to the main chassis. To fill the reservoir with oil, you remove the sump's upper ring by loosening six screws. After placing the tiny ball atop the spindle, you dribble oil onto the ball, letting it flow down the shaft and into the reservoir, until there's a pool of oil about 1mm deep. Then you slide the equally massive spindle bushing over the top, to capture the ball. Then you rotate the bushing to circulate the oil. Add oil until it's level with the top of the reservoir, then place a pair of O-rings in the grooves, sandwiching the upper ring you've previously removed. To seal the reservoir, tighten the screws.

Then it was time to hoist the platter and lower it over the bearing, and here we ran into trouble: The platter, still cold from shipping, wouldn't fit over the spindle. It got stuck, and removing it wasn't easy. Schwartz had to leave, so he called in Michael Trei, his go-to setup man, and the guy I recommend when people ask for someone good to set up a turntable after I've had to turn them down. (I don't have time.) By the time Trei arrived, the platter had warmed up, and now it slipped over the spindle, if still not all that easily. We looped the clear drive belt over platter and pulley, adjusted the tension, plugged in the motor controller, and the platter began spinning.

The L-1's two speeds of 33 1/3 and 45rpm can be individually adjusted with a pair of concentric, vernier-type dials toward the front that, depending on where you place the controller, can too easily be nudged during everyday record playing; it's a good idea to regularly check the speed with a strobe.

Sperling supplied two armboards: one each for my Kuzma 4Point and Sperling's own TA-1 arm. Since I was familiar with the Kuzma but not the TA-1, I began by setting up the 4Point. That done, it was time to play an LP.

Hmmm. . .
Sperling has gone to great lengths to produce a dense, dead, high-mass, energy-absorbing and -draining aluminum platter that's among the most massive I've encountered. But for reasons I don't understand, they chose to top the platter with eight raised, wedge-shaped "exserts" (ie, the opposite of inserts) that attach to the platter top with tiny screws. The record rests atop the exserts—and that's the problem. An LP is a relatively lightweight piece of plastic that, if not damped or tightly coupled to the platter surface, easily transmits energy produced at the stylus/groove interface. That's why we have record mats, clamps, and weights—to damp the disc and prevent it from vibrating and feeding back to the stylus unwanted energy. Mats with raised discs or rings may be useful on inexpensive turntables, but not for ones with 60lb platters.

When an LP is tightly coupled to the platter, it's damped. Resting it atop the L-1's exserts produces open spaces that allow the record to vibrate. Sperling offers exserts in a variety of materials, each of which the company claims produces a slightly different sound—but why not just tightly couple record to platter and avoid having to tune it altogether?

With the stylus on a record and the platter at rest, a gentle tap on the record's label produced a loud, deep thump. The volume of this thump was reduced when I used the Stillpoints or Kuzma record weight on the Sperling's spindle, and even more when I used a well-damped record mat, such as Merrill-Scillia's E.D.M. lead-and-cork mat (no longer made) on top of the exserts. No more deep thump. After auditioning the L-1 with and without the mat, I left the mat on the platter for all of my listening—the bottom end sounded faster and nimbler.

With the Lyra Atlas cartridge on the Kuzma 4Point, immediately obvious was the L-1's rock-solid speed stability, which I later confirmed by measuring it with Dr. Feickert Analogue's PlatterSpeed app (fig.1). Low-pass filtered (fig.2), the results were ±0.5Hz (absolute) and ±0.01% (relative).

The L-1 produced solid, stable imaging, clean and precise transient response, and the dynamic slam and authority managed by only the best turntables: free of low-frequency overhang, but capable of reproducing any harmonic richness contained in the groove and none that isn't. But if you demand romance from all of your records, look elsewhere—or add it with a warm-sounding cartridge or tonearm. The L-1 is a 'table you can put a stethoscope on with a record playing and hear nothing from the motor or the grooves. You can tap on its base or arm mount and also hear nothing.

Listening to the L-1
An evening of piano recordings, both solo and with jazz combos and orchestras, confirmed the L-1's impressive speed stability and pitch control (as long as the record had been pressed concentrically). While the L-1's bottom octaves weren't quite as extended, generous, or forceful as the Continuum Caliburn's, its bottom-end grip and rhythmic authority were. The Sperling's low-frequency starting and stopping abilities were up there with the best I've heard, though I've heard more low-frequency weight from some other 'tables.

---

Footnote 1: Sperling-Audio, Medientechnik Sperling, Blumenstrasse 10, 59514 Welver, Germany. Tel: (49) 2921-3509390. Web: www.sperling-audio.de. US distributor: Audio Arts (2015), 210 Fifth Avenue, New York, NY 10010. Tel: (212) 260-2939. Web: www.audioarts.co. Sonare Coeli (2024), 1170 Oriole Drive, Oconomowoc WI 53066, USA. Tel: (715) 412-4139. Web: www.sonarecoeli.com/.