Listening #67

I can't help wondering: how did the mainstream audio press, cheered Dynaco and Marantz and McIntosh and Quad for switching to transistors a couple of generations ago, greet the first tube-revival products from Audio Research and the like? What was the reaction when moving-coil cartridge technology, considered all but dead by the early 1970s, became the perfectionist hi-fi norm just a few years later? And what would the same people make of the fact that a high-mass, transcription-length pickup arm—with interchangeable pickup heads, no less—is one of the most recommendable phono products of 2008? The mind boggles.

One certainly can't accuse EMT Studiotechnik GmbH of living in the past. Notwithstanding the recent, untimely death of CEO Walter Derrer, the privately held German firm has been conspicuously active in the past few years—their iconic logo now graces a broadcast-quality CD player (the EMT 986), not to mention two very new phono cartridges (the EMT JSD 5 and JSD 6).

Yet the design ingenuity and build quality of EMT's earliest playback products has not ceased to enchant generation after generation of hobbyists, right through to today. Consequently—almost uniquely—EMT has continued to manufacture certain of their products virtually unchanged for almost a half a century, including the OFD 25 and TSD 15 cartridges. Now, after years of requests from hobbyists and professionals alike—whose numbers include the influential designer-distributor Keith Aschenbrenner, of Munich's Auditorium 23—EMT has put their famous 997 "banana" tonearm ($4995) back into production (footnote 1).

The 997 tonearm of 2008 is no mere approximation of a venerable classic, ‡ la the disappointing (to me) AR turntable of 1983: This is the real banana. Three years ago, EMT coaxed foreman Rudi Glaser out of retirement to help put the 997 back into production. Herr Glaser, now 81, dusted off the various jigs and tools necessary for precision tonearm work, and taught his skills to one of EMT's younger (fiftysomething) engineers. The rest, as they say, is history: the sort of thing modern audiophiles would do well to ponder when they're being smacked by the next wave of progress.

Description
Launched in 1974 and derived from an original Ortofon design, the EMT 997 tonearm was intended as a modern supplement to the legendary EMT 927 turntable, itself introduced in 1958. That turntable was noted for its size as much as anything else, and incorporated an idler-driven platter measuring some 44mm in diameter, to accommodate the 16" acetate discs then commonly used in broadcast studios.

Now: In order for a pivoted arm to reach from the outermost to innermost groove of an oversized disc and still offer perfect stylus-to-groove tangency at two points—and minimally imperfect tangency everywhere else—within its modulated area, that arm must itself be oversized. Consequently, the EMT 997 tonearm was designed with a mounting distance of precisely 297mm from spindle to pivot; that dimension, combined with the 10mm overhang specified by its makers, resulted in an effective length, from stylus to pivot, of 307mm, or about 12".

Thirty-odd years following its introduction to the professional market, the broadcast-quality EMT 997 offers a potential windfall to domestic users: Just as distortion can be held to acceptable levels by using an oversized arm to play oversized discs, so can distortion be lowered by using that oversized arm to play smaller discs—in this case, 12" LPs. Like other very long arms, such as the well-loved SME 3012 (a model designation whose last two digits stand for exactly what you think they do), the EMT banana, when set up in accordance with a comparable twin-null-point alignment, achieves a smaller deviation from tracking-angle perfection than would a shorter arm. Lower tracking-angle error translates into lower distortion.

It may also translate into considerably less stress on the stylus, cantilever, and suspension: As record size stays the same and arm length increases—which is to say, as the radius of the arc traced by the stylus becomes more like the ideal straight line from the center of the record spindle—the cartridge offset angle required to achieve two-point perfection decreases. That offset angle is responsible for the force vector, which, combined with stylus friction, produces the well-known skating effect.

So longer arms equal less distortion. But that equation has its limits: To make an armtube longer without a sacrifice in rigidity is to increase its mass. Beyond a certain point, a very massive arm becomes useless with a phono cartridge of reasonable compliance. In the peculiar world of phonography, where the laws of Isaac Newton and Robert Hooke intersect, groove modulations must move the stylus without also moving the cartridge body—yet record imperfections and the spiral groove must be able to move them both.

Happily, as one door closes, another one cracks open: The moderately high mass of an arm such as the EMT 997 can, in fact, make it ideal for use with certain, often old-style, low-compliance moving-coil cartridges. As we'll see, the EMT tonearm invites, even encourages such combinations.

Installation
The EMT 997 is available in two versions, depending on the type of headshell connector desired. More popular by far is the "international" or "universal" connector (also sometimes called the "SME standard"), in which the four signal pins are arranged in a square. International connectors are male-to-male affairs, with exceptionally short pins protruding from the end of a headshell bayonet, and four corresponding spring-loaded pins molded into a plastic disc recessed into the end of the armtube and held tight with a screw. (I deserve a medal for making it through that entire sentence without making a single childish joke.) Alternatively, one can buy the 997 with an EMT-specific T-connector, in which the pin array is rotated 45°, thus turning the square pattern into a diamond. At various times, some of EMT's own cartridge/headshell units—I'll call them pickup heads from here on—have been available only with T-connectors; today, most, if not all, EMT pickup heads are available with international connectors, designated by the letter i next to the EMT logo.



Footnote 1: The EMT 997 is a fixed-pivot, high-mass tonearm with detachable headshell. Effective mass: 35gm. Mounting distance (spindle to pivot): 297mm. Effective length (stylus to pivot): 307mm. Overhang: 10mm. Price: $4995. Manufacturer: EMT Studiotechnik, GmbH, Industriestrasse 25, D-77972 Mahlberg, Germany. Tel: (49) (0)7825-877-18-11. Fax: (49) (0)7825-877-18-15. Web: www.emt-studiotechnik.de. US distributor: Tone Imports, LLC. Tel: (646) 425-7800. Web: www.shindolabs.com.
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