Tonearm Reviews

Ideally, LPs should be played with the pickup stylus remaining tangential (ie, at a 90° angle) to the groove—just as the lacquer from which the LP was ultimately stamped was cut in the first place. Over the years, many attempts have been made to accomplish this. Back in 1877, Thomas A. Edison's original machines tangentially tracked his cylinders, but Emil Berliner's invention of the flat disc put an end to cylinders altogether. In the 1950s, a number of companies marketed so-called "tangential" trackers that used dual arms, based on conventional pivoting arrangements, to change the angle at which the headshell was mounted as it moved across the LP side. In 1963, Marantz introduced the SLT-12, which used a plastic pantograph to move the stylus across the record surface. Garrard's Zero 100 pivoting arm controlled its independently pivoting headshell with a bar that extended from the main bearing of the tonearm.

Spiral Groove's new Centroid tonearm ($6000) arrived just a few days before press time, so it would be risky to say anything definitive about it. But I will take that risk: using the system described in my">http://www.stereophile.com/turntables/spiral_groove_sg2_turntable/">my review of the SG2 turntable, this may be the best tonearm I've heard. Its sound is different in ways that will open people's ears, and I predict that it will affect the design of every tonearm from now on. The Centroid's design deserves and will await full coverage in its own review, but here are the basics: It's a fluid-damped unipivot design unlike any other that gives the user fine adjustment of all relevant parameters.

While brushing my teeth this morning, it occurred to me that there are significant similarities between a toothbrush and a tonearm/cartridge. The bristles would be analogous to the cartridge and the brush handle to the tonearm. In either case it is the business end of the device that does all the work. The bristles track the contours of your ivories in search of hazardous waste deposits, while the cartridge tracks the record groove transducing wall modulations into an electrical signal. I think that this is where the old adage came from: "A used cartridge is like a used toothbrush—nobody wants one!"

Remember Rube Goldberg? He was a cartoonist during the late 1920s to early 1950s who specialized in devising the most outlandish and ingenious devices ever conceived by man, before or since. A Rube Goldberg mousetrap, for example, would occupy an entire small room. In taking the bait, the mouse would tip a balance beam, dropping a steel ball into a gutter, down which the ball would roll to strike a paddle whose spin would wind up a string that hoisted a weight into the air until it reached a trigger at the top, which would then release the weight to drop onto the unsuspecting mouse. Splat!

The Graham">http://www.stereophile.com/tonearms/400">Graham Engineering 1.5 tonearm, originally introduced in 1990, was a thoughtfully executed design that logically addressed all of the basics of good tonearm performance—geometry, resonance control, rigidity, dynamic stability—with effective, sometimes ingenious ideas, while providing exceptional ease and flexibility of setup. Over time, designer Bob Graham came up with ways to significantly improve the 1.5's performance, including the replacement of its brass side weights with heavier ones of tungsten, an improved bearing with a more massive cap, various changes in internal wiring, a far more rigid and better-grounded mounting platform, and a new, sophisticated ceramic armwand. (The original wand had hardly been an afterthought: its heat-bonded, constrained-layer-damped design consisted of an inner tube of stainless steel and an outer tube of aluminum.) The arm's name changed from the 1.5 to the 1.5t (tungsten), then the 1.5t/c (ceramic), and on to the 2.0http://www.stereophile.com/tonearms/401">2.0;, 2.1, and 2.2http://www.stereophile.com/tonearms/401/index7.html">2.2;.

The lacquers from which LPs are pressed are cut in a straight line, and that's how the LP groove should be traced. Even when set up perfectly, a pivoted arm describes an arc across the disc surface, maintaining tangency to the groove at only two points on that arc. Yet despite numerous attempts at building and selling linear-tracking tonearms, few remain on the market, and most are fraught with technical problems. Linear-tracking arms can be anything but linear, committing more sins of geometry as they meander across the record surface than do their pivoted brethren.

The best tonearm I ever heard was a second-generation Mission Mechanic, ca 1986. It was mounted on a Roksan Xerxes turntable, and I spent several happy hours listening to records on that combination (with a low-compliance EMT cartridge) in two very different systems: one with solid-state amplification from DNM and Roksan's own dynamic Darius loudspeakers, and the other—my home system of the time—using tube amplification from Conrad-Johnson and a borrowed pair of Stax electrostatic speakers.