The UNI-DIN curve is available commercially via the Acoustical Systems Smartractor ($599, footnote 5), a phono-alignment protractor described by the manufacturer as "universal" inasmuch as it can be used with virtually any pivoting tonearm. Like Dennesen's popular Geometric Soundtracktor before it, the Smartractor has much in common with a draftsman's beam compass: here, the beam is a 13"-long rod of square cross-section, machined from polyoxymethylene (POM), that slides along a block of POM that has both a locking screw and a vernier scale. Fastened to one end, perpendicular to the beam, is an adjustable steel rod, machined at its lower end to a point that's intended to contact the precise center of a tonearm's lateral bearing; for tonearms whose pivots are difficult to discern, the upper end of this rod is fitted with a clear plastic disc marked with a scale inscribed on a transparent surface.
The block and beam are fastened, through various fittings, to a semicircle-plus of mirrored plastic, the top of which is engraved with a series of reticles and information. Because the Smartractor can precisely lock on to the tonearm pivot, dual alignment grids aren't required for accurate results: only a single grid is required, just as in the Dennesen Soundtracktor. That said, the generously sized Smartractor is engraved with five grids, for five different alignment schemes: UNI-DIN, Löfgren A (IEC), Löfgren A (DIN), Löfgren B (IEC), and Löfgren B (DIN). In brief, Löfgren A is Erik Löfgren's original, 1938 alignment. In its IEC version, the innermost null point is set at 60.325mm from the spindle center, in accordance with the LP-manufacturing standards set by the International Electrotechnical Commission; in its DIN version, the innermost null is at 57.5mm, in accordance with DIN standards. Löfgren B is a variation that Löfgren devised for players in which the offset angle is both nonadjustable and suboptimal—this according to engineer Graeme F. Dennes, in a paper that is a landmark traversal of studies of the subject (footnote 6); the IEC- and DIN-prescribed nulls are consistent with the above.
I love my cartridge
The Smartractor is ergonomically friendly, and its readings are easier to see and interpret than those of the outwardly simple DB Systems DBP-10 protractor I've relied on in recent years. The user removes a thumbscrew that secures the block-and-beam assembly to the protractor, then rotates the block relative to the beam to choose one of the five alignment schemes, after which the thumbscrew is reapplied to lock the settings in place. A sixth setting, labeled UNI P2S, allows the beam to be used to measure the pivot-to-spindle distance. The vernier scale ends at 315mm—a slight disappointment, given that the P2S distance of my EMT 997 tonearm, when set up for use with a G-style pickup head, is 316.325mm—but the beam seems long enough to accommodate, if not measure with precision, arms with P2S distances of up to 318mm.
After the alignment grid has been chosen, the Smartractor is lowered to the platter. Its 9mm spindle hole is an intentionally loose fit: with the protractor in place, a short nylon tube—it tapers in thickness from bottom to top—is then pressed down onto the spindle, to center the Smartractor and hold it in place. With the protractor thus positioned and its beam's pointer either aimed at or in contact with the center of the tonearm pivot, the user lowers the stylus and adjusts the cartridge position as needed, until the stylus drops neatly into a dimple on the grid, and the cantilever lines up with the appropriate engraved lines. A cutaway in the clear-plastic fitting between the beam-and-block and the protractor holds a magnifying loupe (supplied) in just the right position to aid alignment—a very welcome enhancement.
The Smartractor is a breeze to use, and seems exceptionally well made. But what of the alignment curves it offers? I have yet to use all five, and my experiences with the Smartractor are limited to a very few cartridges. Most of the cartridges I own, such as my various EMT OFDs and Ortofon SPUs, are pickup heads, whose fixed offset angles and overhangs force me to use the DB Systems protractor. The DB is still the only commercial protractor I know of that makes it easy to select and then implement my own (dual) null points, arrived at by using the Arm Geometer software developed by Keith Howard and referenced in "Arc Angles."
I made a few listening notes during my early experiences with the Smartractor. In fact, this column began as the introduction to a piece about two new and very expensive standard-mount cartridges—but in my efforts to say a few preliminary words about the work that went into setting them up, I found that the Smartractor deserved more ink: those cartridges will appear in this space in the next issue.
So I reverted to an old friend among standard-mount cartridges, my well-worn Miyabi 47, which hasn't been in production for a number of years. I chose the Miyabi especially for its relatively spare body, and thus its easy-to-see cantilever: always a boon to precise alignment. And its elliptical stylus is, I suppose, closer than the spherical tips of my various pickup heads to the sorts of styli most hobbyists use. Not only that, audible differences among various alignment settings are presumed to be more apparent with an elliptical (or any of its many variants) than a spherical tip.
I began by setting up the Miyabi 47 with Löfgren A (IEC) alignment, then spun a few LPs, including: Captain Beefheart & His Magic Band's Strictly Personal (Blue Thumb BTS 1); the Incredible String Band's Liquid Acrobat as Regards the Air (Island ILPS 9172); Elgar's Sea Pictures, performed by mezzo-soprano Janet Baker, Sir John Barbirolli, and the London Symphony Orchestra (EMI ASD 655); and Donovan's Barabajagal (Epic BN 26481). I made sure to spend at least a little time listening to the first and last tracks on most of those sides. I enjoyed generally good sound with Löfgren A (IEC), and mentioned in my listening notes that Mike Heron's lead vocal in "Painted Chariot," the last song on side 1 of the ISB album, sounded very present and very good.
Then I repositioned the cartridge in its headshell to achieve Löfgren A (DIN) alignment—which, it seemed to me, required just over 1mm less overhang, and a hair less offset. As with the initial setting, this alteration took a bit of patience: not infrequently, I found I'd inadvertently moved the cartridge while retightening the mounting bolts—which I'd loosened in order to move the cartridge in its headshell.
From my notes: "With DIN, the beginning of Elgar's 'The Swimmer' definitely sounded a little worse—grainier and harsher, especially in the voice and massed strings. But the very end of the song sounded microscopically better—in particular, Baker's loud, sustained high A at the end. (Baker's voice is dead center, while the no-less-loud orchestra, which sounded no different, comes at the listener from both sides of the stage—make of that what you will.) In ISB's 'Painted Chariot,' Heron's voice didn't sound quite as good—a difference so slight I might have imagined it—but the loud organ at the end sounded worse in DIN—obviously more distorted." For the record, "The Swimmer" begins at about 90mm from the spindle center and ends at about 70mm; "Painted Chariot" ends at 63mm.
I left the Miyabi 47 in its Löfgren A (DIN) position for the rest of that day, listened to a few more records, and the next day resumed listening with Donovan's Barabajagal—chosen because I remembered measuring its modulated groove area a few years ago and noting that, on side 1, it goes all the way to a point just 57mm from the spindle center. For that reason, this LP was a useful choice, but it was a poor choice in another respect: Barabajagal has not, shall we say, held up very well. Listening to that side 1 closer, "I Love My Shirt," was an exhumation from which a few foul odors escaped, made worse by the fact that, at the time, my college-age daughter and her boyfriend were within listening range: much ribbing ensued. In any event: the side 1 opener (the title track) sounded really quite good, but by the end of "I Love My Shirt" cymbal smashes were a little hot, lead and backing vocals harsh.
I made a few more notes, then repositioned the cartridge for UNI-DIN alignment. "Barabajagal" was now worse than with Löfgren A (DIN)—per my notes, by the end of the track it was "borderline unlistenable." At first, "I Love My Shirt," which begins at around 77mm, also sounded worse, but not by as much: Donovan's voice was just a little more sibilant. Yet by the end of the song the sibilance was more natural and thus easier to take. With UNI-DIN, his voice at the end of the track sounded better than ever.
But let's be realistic: This was with one cartridge and a total of maybe a dozen LPs, heard over the course of two days. Over such a brief time and with so small a sampling, variables that might otherwise pale into insignificance—cartridge bolts tightened to different degrees, different ambient temperatures, etc.—can influence or even swamp distinctions that might prove more consistent over the long haul.
And the long haul is what I'm in for. With the indulgence of Acoustical Systems, I intend to keep using the Smartractor, which is more pleasant to work with than any other alignment product I've used, regardless of curve(s). For now, because Löfgren A (DIN) has worked for me so well for so long—from a technical point of view, I believe it's closest to what I've used in recent years with the combination of the DB Systems protractor and Keith Howard's Arm Geometer software—I'm going to keep that as my control. Hopefully, in time, I'll have a better-informed idea of which alignment scheme provides the most listening enjoyment long-term. My mind is open: as Deng Xiaoping famously said, "It doesn't matter whether a cat is black or white, if it catches mice it is a good cat"—a statement that put him at odds with Jiang Qing, whose mistrust of all things Western never dimmed.
Footnote 5: Acoustical Systems, Am Büchele 2, 86928 Hofstetten, Germany. Web: www.arche-headshell.de. US distributor: Rutherford Audio Inc., 12649 E. Caley Avenue, #116, Centennial, CO 80111. Tel: (303) 872-6285, x8003. Web: www.rutherfordaudio.com.
Footnote 6: Graeme F. Dennes, "An Analysis of Six Major Articles on Tonearm Alignment and Optimisation and a Summary of Optimum Design Equations," AES/IEEE, 1983/2015.
The Smartractor is ergonomically friendly, and its readings are easier to see and interpret than those of the outwardly simple DB Systems DBP-10 protractor I've relied on in recent years. The user removes a thumbscrew that secures the block-and-beam assembly to the protractor, then rotates the block relative to the beam to choose one of the five alignment schemes, after which the thumbscrew is reapplied to lock the settings in place. A sixth setting, labeled UNI P2S, allows the beam to be used to measure the pivot-to-spindle distance. The vernier scale ends at 315mm—a slight disappointment, given that the P2S distance of my EMT 997 tonearm, when set up for use with a G-style pickup head, is 316.325mm—but the beam seems long enough to accommodate, if not measure with precision, arms with P2S distances of up to 318mm.
After the alignment grid has been chosen, the Smartractor is lowered to the platter. Its 9mm spindle hole is an intentionally loose fit: with the protractor in place, a short nylon tube—it tapers in thickness from bottom to top—is then pressed down onto the spindle, to center the Smartractor and hold it in place. With the protractor thus positioned and its beam's pointer either aimed at or in contact with the center of the tonearm pivot, the user lowers the stylus and adjusts the cartridge position as needed, until the stylus drops neatly into a dimple on the grid, and the cantilever lines up with the appropriate engraved lines. A cutaway in the clear-plastic fitting between the beam-and-block and the protractor holds a magnifying loupe (supplied) in just the right position to aid alignment—a very welcome enhancement.
The Smartractor is a breeze to use, and seems exceptionally well made. But what of the alignment curves it offers? I have yet to use all five, and my experiences with the Smartractor are limited to a very few cartridges. Most of the cartridges I own, such as my various EMT OFDs and Ortofon SPUs, are pickup heads, whose fixed offset angles and overhangs force me to use the DB Systems protractor. The DB is still the only commercial protractor I know of that makes it easy to select and then implement my own (dual) null points, arrived at by using the Arm Geometer software developed by Keith Howard and referenced in "Arc Angles."
I made a few listening notes during my early experiences with the Smartractor. In fact, this column began as the introduction to a piece about two new and very expensive standard-mount cartridges—but in my efforts to say a few preliminary words about the work that went into setting them up, I found that the Smartractor deserved more ink: those cartridges will appear in this space in the next issue.
Footnote 5: Acoustical Systems, Am Büchele 2, 86928 Hofstetten, Germany. Web: www.arche-headshell.de. US distributor: Rutherford Audio Inc., 12649 E. Caley Avenue, #116, Centennial, CO 80111. Tel: (303) 872-6285, x8003. Web: www.rutherfordaudio.com.
