Analog Corner #318: Turntable setup is a diagnostic exercise

As I watched WAM Engineering's J.R. Boisclair give an advanced turntable setup seminar at last November's Capitol Audiofest, a light went off. I'm being figurative, but the lights didliterally—go off, and then on again, as I flipped the switch for Boisclair's presentation (see the above photo), which featured both screen time and an in-person lecture.

Boisclair's presentation did not include setting up an actual, physical turntable. Rather, using slides and 1000:1 scale 3D-printed groove and stylus models, he dug into the advanced concepts involved in setting up a turntable and why those concepts matter.

After the presentation, a few people asked me if I was comfortable playing "second fiddle" when I'm usually up there myself doing the talking. I told them I'm perfectly happy flipping light switches and learning from the successor to the abundant Wally Malewicz knowledge base. After all, most of what I know about the subject came directly from Wally, a mechanical engineer, who, while not infallible, was most often correct.

Boisclair is not a mechanical engineer, but he was Wally's longtime friend and assistant. Today, he is assisted by Wally's son Andrzej, who, like Wally, is a mechanical engineer. He is vice-president of R&D at Medtronic, a giant healthcare tech company.

The light that went off for me during the presentation was the realization that correctly setting up a turntable is as much an exercise in diagnostics as it is in getting the cartridge precisely aligned in the tonearm.

I usually try to avoid setting up turntables for other people, but Boisclair's mostly theoretical presentation had me flashing back to some setup experiences I've had, beginning with my +1 date to Jack White's pressing plant grand opening in Detroit's Cass Corridor back in February 2017.

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Mikey flanked by contest winner "The Boogie-Down" (L) and Jack White.

Just to be clear, this wasn't a "date"-date (though he turned out to be an attractive man). My wife didn't want to attend the event, so I ran a contest on AnalogPlanet, and this reader won, so he was my date. He had to pay his own way, but he was thrilled to win, and the evening was as much fun as we'd hoped it would be and included having a photo taken with Jack White.

Afterward, he called me to ask if I could help his friend with a stubborn turntable problem. "Of course, happy to help," I replied.

I heard from the friend a few days later.

He told me he had a 9" Kuzma 4Point tonearm mounted on a Dr. Feickert Woodpecker turntable fitted with a Lyra Etna cartridge. He'd bought it all new and had it set up by someone he trusted to do a good job, but neither he nor his wife were satisfied with the sound. It just sounded "off," he told me, though he couldn't be more specific.

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A Lyra Etna cartridge skewing heavily to the left.

He told me that over time the Etna's cantilever began to skew so far left that it interfered with tracking, and the sound seriously suffered. Off to Lyra went the Etna via Etna importer AudioQuest, and he was left for quite some time with no vinyl playback—too bad because vinyl was his main musical source.

Months later, the same person who installed the cartridge the first time reinstalled the repaired cartridge. Soon thereafter, it again began to skew. This time, the unlucky 4Point owner called me before the cantilever got too far off. I listed every 4Point setup error and mechanical culprit I could think of and asked him to check them all. Everything appeared normal as best I could ascertain at a distance.

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WallySkater showing a large deviation with a Kuzma 4Point tonearm.

I've known for some time that the antiskating weight Kuzma supplies (or perhaps used to supply) with the 4Point is too heavy and that adjusting the weight's position per Kuzma's instruction manual produces excessive antiskating force. Even placing the weight as close as possible to the pulley to fully minimize antiskating force turns out to be excessive with many cartridges.

How do I know that? Because I have the WallySkater tool from WAM Engineering. While setting antiskating is intrinsically an exercise in imprecision, this tool offers a reliable, relatively precise way to set it; its settings are corroborated by the other worthwhile antiskating setting accessories. (Telarc's Omnidisc for instance; the grooveless-record approach is not worthwhile, in my opinion.) For more about antiskating, please read "Everything You Know About Skating Is Wrong!" at AnalogPlanet. Kuzma, along with American importer Elite Audio/Visual Distribution, is now said to be including a lighter antiskating weight with 4Point arms.

It was time for me to meet this unlucky 40-something vinyl enthusiast and examine his turntable in person. He brought it over. As we talked, it became clear that he was disappointed with the whole course of his investment and ownership of this costly analog front end. It wasn't a casual purchase, and he felt he'd done it the right way, buying the arm from a dealer and having it properly set up by someone who ought to have expertise—so what was going on?

The first thing I did was put the WallySkater device on the arm. The WallySkater suspends the arm from a string hanging from a crossbar; at the end of the string is a loop you place around the finger lift, allowing the arm to dangle free in space. The antiskating force applied to the arm, by whatever means—string/weight, magnetic repulsion, etc.—should move the suspended arm toward the platter's outer edge. A plumb bob acts as a vertical reference, and a segmented plastic rulerlike platform allows you to measure the distance between the plumb bob and the string looped around the finger lift.

When antiskating is disabled, the plumb bob and loop should line up with one another, more or less. When the antiskating is engaged, the arm should move rightward—toward the outside of the record—and the distance between the bob and loop should be approximately 8–12 segments of the ruler's markings, depending on the length of the arm and the tracking force applied. This is also a good way to check out the vertical bearing's free play. (The vertical bearing is the one that controls horizontal movement.)

If the arm sticks, something is seriously wrong.

Once, in front of a few hundred people at a show in Copenhagen, Denmark, and televised on a big screen, I discovered an expensive, sticky arm—embarrassing for the manufacturer. We chalked it up to shipping damage. Had a dealer installed it and not had a way to check the bearing movement, it might be playing (poorly) today in some unlucky audiophile's system.

The photo shows a different individual's 4Point with a 20+ WallySkater deviation produced using the larger Kuzma antiskating weight. Someone had set it approximately and clearly incorrectly. That's way too much antiskating force. Although it's not visible in the photo, the cantilever's slant is evident even with a stationary platter.

But back to the 4Point 'arm in question: When I suspended this 4Point arm it swung wildly, almost violently, rightward. I'd never seen anything like it. I removed the antiskating weight from the lever and the arm continued to swing wildly. I disabled the lever and this odd behavior persisted. What in the world?

I separated the arm from the platform on which it rests so that I could examine two of the 4Point's four points—the ones responsible for the arm's vertical movement. They appeared normal, as did the cups they sit in. The post in which sit the other two points—the vertically arrayed pair that support horizontal movement—felt as if they were correctly positioned within the vertical post, but this is a sealed structure. Clearly, the excess rotational force producing the wild rightward swing would require diagnosing by Franc Kuzma.

ARTICLE CONTENTS

COMMENTS
georgehifi's picture

Quote.
"Tracking force using a high-quality digital scale"
"I used a digital stylus force gauge to set tracking force"
"I set the Etna's stylus rake angle (SRA) using a digital microscope"
"I measured channel separation with a digital oscilloscope"

Cheers George

miguelito's picture

:)

mcrushing's picture

Digital tachometers to ensure the accuracy of the
Digital oscillator in your motor controller that
Spins records cut from digital sources
To feed to your ADC, your Sonos or Kii Threes!

I own none of that stuff, but if you do and your foot is tapping, you're doing it right.

Why fight when we can dance??

Michael Fremer's picture

The thought that the irony is lost on me or the observation is novel.

mcrushing's picture

I'd never dream of suggesting otherwise, Mikey!

I normally keep out the analog/digital debate. A person's preference for bits vs. wiggles oughta be his own affair...

Personally, I'm not sure it's possible to say which is the more "accurate" of the two formats. I can sure as hell tell you which one brings me more joy.

Michael Fremer's picture

In the service of better analog is good. These are mostly static measurements as opposed to music, which is a moving target and less well served by digitization in my listening experience.

Jack L's picture

Hi

Bingo !

Listening is believing

Jack L

JRT's picture

The link in footnote 2 points to Art Dudley's Listening #147 which is one of the few not mentioning the Thorens TD-124.

The following link points to the many Stereophile webpages which do include mention of the TD-124.

https://www.google.com/search?q=site%3Astereophile.com+td-124

JRT's picture

https://www.stereophile.com/content/thorens-td-124-dd-record-player

In that article, Ken Micallef mentioned, "... its two-part platter including a flywheel [subplatter], crafted in stabilized cast iron, [which] possesses excellent characteristics for the magnetic shielding of the drive system...," and, "...the original platter's ferromagnetism attracted the magnets in cartridges."

Maybe add this one:
https://www.stereophile.com/content/listening-61-page-2

Art Dudley mentioned, "Some hobbyists have suggested that, for the Mk.II, Thorens replaced the iron platter of the original with a nonmagnetic aluminum one, but the latter seems to have existed only as an extra-cost option during the late 1960s. Predictably or not, most hair-shirt anachrophiles opine that the magnetically permeable iron platter sounds much better, notwithstanding its nasty habit of destroying phono cartridges in more or less the way the planet Mars is thought to destroy exploratory spacecraft. In any event, my Mk.II has the iron platter."

bhkat's picture

It's great to hear you going out of your way to help someone.

miguelito's picture

Could you detail your process? What I have done is use the AP test record and play the tracks with L or R tone and measure on the scope the R or L output so that they are as small as possible - if they are the same I am done. In this process I use only one of the phono pre channels to avoid the possible diff in gain in each channel - eg use the R and plug the L lead to measure how low L is when I play the track with signal only in the R channel.

But how are you determining the dB?

Glotz's picture

Mikey going the extra mile not for just the column but for a analog fan that was stuck in a bad situation and without the knowledge to diagnose it for himself.

I love this concern! Who else would go to these lengths as a writer/columnist??

eatapc's picture

This is a keeper. Very good explanation of the problems one can encounter even knowledgeable about setup.

Timbo in Oz's picture

I began doing this as a part-time earner a good way back and some of my articles may still be on line. I used and still have a Dennesen protractor, and two kit boxes for checking channel balance and separation.

Duratone, the only decent audio shop in Canberra used to give me work at folks homes. There are basic principals for dynamic speakers and panels. Add a tape measure and decent mental maths skills and you have a happy client. I always tried to sell the set-up to the boss - aka the bloke's wife! ;-)

Didd't bring in a LOT of money, so I stopped.

deckeda's picture

Thanks, Michael for sharing that one owner's journey. "Incredulous." Yeah, Frank, imagine our surprise at learning expensive gear can be defective!

Now I know not to invest in a new cart, wasting money before I can install it properly. I mean, I always knew it but I super really know it.

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