Analog Corner #31

(Originally published in Stereophile, February 12th, 1998)

Ever have one of those days from hell that starts before the sun comes up and doesn't end until you fall into bed exhausted and stressed, hours after your normal snooze time?

I had one a few weeks ago. I'll spare you the 6am phone call that started it, but by noon I'd learned that my furnace was cracked and a new one would cost me $3000. Three grand? What a waste. That almost buys a state-of-the-art phono cartridge or some good cables these days, and I have to divert it to heat?

The compensatory dinner out didn't result in E-Coli poisoning, but the day's toxicity wasn't over: we returned home to flashing red lights and cops combing the grounds with flashlights.

"False alarm," one officer assured me, returning to his car. Another—the supervising Sergeant, as it turned out—walked up and said, "It's a funny coincidence, but when the alarm call came in, I was reading your article on the Oracle turntable in the new Stereophile."

Small audiophile world, don't you think? He's got the Krell integrated amplifier and some Snell speakers—another coincidence: the restaurant we'd come from also had Snell speakers—and he told me this column had just about worn down his resistance: he was thinking about resurrecting his AR 'table. I told him I'd be happy to do the cartridge setup, while telling myself to please remember to first check my '60s-vintage collection of cartridge-mounting hardware for seeds and stems—otherwise, I might find myself having a really bad day. (And yes, let's hope he has a good sense of humor, because he just read that too!)

Things we need
I'm writing this on Thanksgiving Day, the memory of the Barney balloon getting stabbed to death by one of NYC's finest—a moment I'll long cherish—fresh in my mind. It got me thinking about how much we analog enthusiasts have to be thankful for as we head into 1998. A few years ago, vinyl was a dirty word. Today it's merely in bad taste in certain circles. Still, there's enough superb new software available to make buying a turntable a viable option for any connoisseur of fine sound.

Between Classic Records, Analogue Productions, DCC Compact Classics, Alto Analogue, Speaker's Corner, ARS, King Super Analogue, WEA Germany, Testament, Mosaic, and the others—and "commercial" labels large and small like Blue Note, Impulse!, Columbia, Warner Brothers, MCA, Elektra, Drag City, Sub Pop, Matador, and on and on—there's an abundance of vinyl few of us could have imagined a few years ago, and plenty of retail mail-order competition to peddle it to us. Every analog enthusiast should be on the mailing lists of Acoustic Sounds, Audiophile International, Quality Vinyl, Music Direct, Elusive Disc, Classic Direct, and the rest. And the used market just keeps on belching up wonders. Then there's the online vinyl resources, which I'm compiling for a future column.

We've also got an extensive choice of new turntables, arms, cartridges, and phono preamps, and a wide range of analog accessories, from vacuum record-cleaning machines to stylus-pressure gauges accurate to a hundredth of a gram. But there are still some things we could really use...

Like the sort of cartridge analyzer Audio-Technica used to make. If audiophiles are willing to spend $800 on an accurate stylus-pressure gauge—and they appear to be—I'm sure many would fork over the going rate for a new high-tech setup device.

We need new and better test records. Hi-Fi News & Record Review's Test Record is a good start, but we need better and more complete diagnostics. One of the audiophile labels should do it, accompanying a series of meaningful tests with music tracks from its catalog—sort of like a cross between the old Shure test records and Bob and Ray Throw a Stereo Spectacular. Among the tests should be long left-channel-only and right-channel-only modulations, to make minimizing crosstalk easy for precise azimuth adjustment.

A reader recently sent me some photocopies of ads for some really useful products that are no longer being made. Anyone ever heard of the Berkshire Match Maker, from the late '70s? It's a pair of switch boxes ($49.95/pair) you insert between your turntable and preamp that allows you to "dial in" both capacitance and resistive loading. You could add from between 50pF to 350pF in 50pF steps, and either 68k ohms or 100k ohms.

Of course, it's for use with moving-magnet cartridges, but how difficult would it be to design one for moving-coils? Few of us would want to keep such a device inserted in the line, but once you'd determined optimum capacitive and resistive loading, perfection would be just a hot soldering iron away. Did you know that NAD's old budget 1020 preamp came with a capacitive loading switch? As reader Gerald Smith demonstrated to me last year, the total capacitive load has a profound effect on a MM cartridge's flat-frequency-response performance.

If the total capacitance (which includes the preamp and both the armwire and interconnect wire) is too high, you get high-frequency rolloff, potentially accompanied by a rise in the upper midrange. The proper capacitive value is related to the internal inductance of the cartridge and the resistive loading—which is not necessarily 47k ohms, even though virtually all MM phono sections are so loaded.

Mr. Smith calculated for me that if a cartridge has 380 milliHenries of inductance (the Shure V-15VxMR, for example, has 425) and the total capacitance is 250pF, the critical frequency below which highs would roll off at 12dB/octave would be 16,329Hz—too low! He then calculated that the optimal resistance of such a combination for flat response would be 27.5k ohms of loading, even though virtually all MM preamps are nominally set to 47k ohms. The result is both high-frequency rolloff and a mild rise between 5 and 10kHz.

We pause momentarily to commemorate the 1/3 point through the 33rd "Analog Corner''...

Lower the total capacitance to 100pF, Mr. Smith writes, and the Fc (critical frequency) rises to 21,080Hz, thus ensuring no audible HF rolloff and an optimal resistance of 35.5k ohms—close enough to the nominal 47k MM "standard" to not require modification. Want to mess with the math? First of all, you'll have to know both your preamp's capacitance and the total capacitance of your interconnect and tonearm wire.

To calculate the critical frequency (Fc), the formula is 1 divided by 29 times the square root of the inductance in Henries times the capacitance in Farads. The optimum resistance calculation is 0.707 times the square root of the inductance divided by the capacitance. Whew! Or, you could have a pair of little boxes that helps you set these things by ear.

By the way, Berkshire Audio Products (of Great Neck, New York, and I assume now defunct) also sold a capacitance meter that could measure the entire path: the tonearm wiring, interconnect, and the internal capacitance of the preamp itself ($89.95).

The rest of the Xeroxed stroll down analog memory lane (supplied by a retiree living on Mallorca—I'm not too jealous) included the Audio-Technica AT 60006a, an end-of-play hydraulic arm lift that I'd forgotten I once owned, and the Nuclear Products Company 3R500 Staticmaster, a "Polonium-treated jaguar-hair brush [that] eliminates static and dust from records." Carcinogenic? Endangered species? When clean records are at stake, who cares?

Our man in Mallorca also sent a blurb on the Swiss-made Spirig illuminated 100-power microscope for viewing styli. The Spirig is still in production and would make a handy accessory; someone should import it. I take cartridges to my local jeweler for inspection: his high-powered stereoscopic microscope for examining gems yields a really clear 3D image.

One key diagnostic device I wouldn't be without is a stethoscope. You can pick one up at a medical supply house or a good pharmacy for about 25 bucks. It's handy for listening in on turntable bearing noise when you go shopping for a new—and especially a used—turntable. Put the business end on the plinth and start the motor: You should hear silence. If you hear a groaning noise that rises in frequency and continues at a steady pitch once the platter reaches speed, you can be sure the vibrations creating the noise are being transmitted directly to the stylus tip.

If you hear noise on a new 'table, the cause is most likely a poorly designed and/or manufactured bearing. On a used 'table it could be wear caused by the previous owner running the bearing with insufficient or no oil. Whether new or used, and whatever the cause, if you do hear noise, don't buy that turntable. While the noise itself might not be audible on a "silent groove" band of a test record, the noise translates into vibrations that make their way through the plinth and into the tonearm, where they interfere with the delicate stylus/groove interface.

I'll tell you another thing we need in this new analog world: a clearinghouse to better inform us as to what's available on vinyl. It's almost like the early days of CD, when a guy named Peter Howard started ICE (International Compact Disc Exchange) to help CD enthusiasts learn what new digitized "treasures" were available, and to facilitate trades of the then-precious commodity among the early adopters.

Today we need an analog command center. I've tried to become an information hub for new vinyl activity by asking pressing-plant managers to fax or e-mail me a list of their output, but despite assurances that they'd do so, none has come through. And you can't ask label publicists what's available because usually they don't know. The only sure way of finding out what's being pressed is to read the mail-order catalogs, subscribe to Goldmine, and read the ads from the nonaudiophile vinyl dealers who frequently have a different mix of product (and sometimes lower prices). Finally, regularly scour the bins of your favorite vinyl shop (if you have one).

Did you know that Morrissey's new album Maladjusted (Mercury 314 536 036-1) is available on 180gm vinyl? I picked it up at Tower for eight bucks! Or that Portishead (London 314 539 189-1) is a two-LP set? More commercial vinyl I've picked up recently: Squirrel Nut Zippers' Hot (Mammoth MR 0137-1), Fountains of Wayne (Atlantic 92725-1), Southern Culture on the Skids' Plastic Seat Sweat (Telstar/DGC TR030), Erykah Badu's Baduism (Kedar/Universal U-53027), Stereolab's Loops and Dots (Drag City, two LPs pressed on white vinyl from British stampers, $14.98), Luna's Pup Tent (Teenbeat/Elektra 232). ("Additional copies are available for $8 from Teenbeat, P.O. Box 3265, Arlington, VA 22203," the inner sleeve of the Greg Calbi–mastered, Europadisk DMM–mastered LP says. If you like good sound—Talking Heads, B-52's, VU—I suggest you take Teenbeat up on its offer.)

Would I have known about these (mostly) great-sounding LPs (I get the CDs from the record companies for review in my magazine) if I hadn't seen them with my own eyes? No. The promo literature doesn't list the vinyl, and the advertisements say "available on CD and cassette." Isn't this...absurd?

Feedback loop
I don't know any reviewer who enjoys writing a negative review. In fact, some feel so uncomfortable doing so, they don't—even when it's deserved. Those reviewers should find a new avocation; neither you nor the industry is served by a mealymouthed writeup. But readers, for the most part, don't enjoy negative reviews either—especially when the skewered product sits on their equipment racks!

I didn't feel my review of the Clearaudio turntable/Souther tonearm last November (Footnote 1) was negative. In fact, most of what I heard and described didn't differ that much from other recently published reviews. Mine, however, was the only one that attempted to deal with the Souther arm's objective performance, which I found flawed in a few key areas, and on which I felt obliged to report. $M1 Vol.20 No.11, p.177.

I was called some choice names (I won't repeat them here) by some Souther enthusiasts, but I did talk with a few—including Bob Gadwood, who gave me permission to print his findings after I suggested he purchase HFN/RR's Test Record and run the tests I used. Mr. Gadwood uses a Clavis cartridge—which is what I used—with his pre-Clearaudio Souther.

While I couldn't measure a vertical resonant frequency on the Souther, which indicated to me that it was above the 16Hz upper limit of the HFN/RR Test Record, Mr. Gadwood heard the 1kHz pilot tone warbling right where it should—between 8 and 10Hz—though he could detect visible arm movement. I can't explain the disparity in our findings. In fact, after the review ran, I heard from a former Souther dealer who corroborated my finding. Still, I now feel obliged to repeat the test at a dealer, and I will report back to you when I have done so. Mr. Gadwood tested a friend's SME V and didn't detect movement there, though he did hear the pilot-tone warble. Understand that, when the vertical resonance point was reached on other arms I've tested (Immedia, JMW Memorial, Graham, Wheaton Triplanar), movement was easily visible—as the Test Record instructions say it should be.

Like me, Mr. Gadwood was unable to detect a lateral resonant frequency, either visually or aurally, meaning it was out of the ideal 8–12Hz range. In his first communication after using the Test Record, Mr. Gadwood did not hear the side 2/band 1 mistracking buzz moving from channel to channel, as I had reported. This really disturbed me—I'd tried everything to stabilize the arm and get it to perform adequately in this regard.

In his next communication, Mr. Gadwood amended his report: "I also went back and listened to the sound of the cartridge mistracking on band 1 of side 2 of the Test Record. And I do hear the buzz move around from side to side. (I hadn't really bothered with the sound of the mistracking before, only what it took to make the arm track.) I took the record to a friend who has a VPI Jr. 'table with (I think) an SME 309 arm. In this case, the mistracking buzz also moved from side to side. It turns out that my copy of the Test Record is a little warped, and the hole is apparently off-center as well. So I think that movement of the mistracking buzz may be an artifact of the specific pressing that I have. As I mentioned in one of my earlier letters, I don't hear any problems with tracking on my Stereo Review test record (no longer in print)."

To reiterate what I wrote in my review: The problem with an undamped linear-tracking arm like the Souther, the Forsell, or the original Eminent Technology is that you're dragging a huge mass along that linear line. Given that many (if not most) records are pressed somewhat off-center, as that mass slides back and forth there's no way the cantilever can avoid being swinged, swayed, and Sammy Kaye'd (for those of you old enough). The result: Instead of staying centered in the groove, the stylus presses on one wall, then the other. And while the cantilever may not snap on such an undamped arm, there's no way the coils attached to it can remain centered in the magnetic gap—where they must, for the cartridge to generate the electric signal in a linear fashion.

Mr. Gadwood described to me a modification that "has a significant effect on the amount of downhill slant needed to get the arm to track equally on both sides." The result of the modification (which has to do with the arm cable and its support and positioning) is that "The bubble on the level is almost exactly centered, with only the right edge touching the black line. The whole method of cable support on this arm is one area where the manufacturer should do a better job."

Needless to say, the modification, which involves a physical change to the product, is inappropriate for a review. I reported what I found: that the arm had to be pointed "downhill" to keep it from sticking in the groove. Mr. Gadwood gave me permission to publish his e-mail address so other Souther arm owners can communicate with him: rgadwoodccm.tds.net .

RCA Dynagroove
When Ayre's Charlie Hansen came by a few months ago to install the K-3 preamplifier (review to come) in my system, he brought with him some photocopies taken from The Audio Cyclopedia, an out-of-print reference book organized in question-and-answer form. One question:

"Describe the RCA Dynagroove stereophonic disc record."

Most of you know that when RCA went from "Living Stereo" to "Dynagroove," the sound, almost instantly, went to living hell. That's why, while many Living Stereo records still command large sums despite the fine-sounding Classic and Chesky reissues, you can't give away most Dynagroove pressings (though there are a few exceptions).

The good news, according to The Audio Cyclopedia, is that Dynagroove is basically a post-production process. Theoretically, many sonically superb, worthwhile performances can be resurrected and reissued. The bad news is what Dynagroove really is: After the 30ips recording is completed, it's transferred to a "submaster tape using a Dynamic Spectrum Equalizer to correct for differences in the listening conditions and to that of the average dwelling. The design of this equalizer is such that its frequency response is altered continuously as the program is recorded....'' At low volume levels, low frequencies got boosted; at medium levels there was a small amount of bass and "presence range" (2–6kHz) boost, and a reduction in the 400Hz–1kHz range; and at high levels, the 2–6kHz range was boosted more, the below-1kHz range attenuated. Oy vay!

But wait! There was more! In the disc-mastering process a device called a Dynamic Styli Correlator "corrects for the discrepancies between the angle of the recorder and reproducer stylus used by the consumer....'' Sixties left-wing collectivism-socialism at its worst! Affirmative action for analog! No wonder most Dynagroove records sound so awful. They probably forgot to fire up the equalizer on the ones that sound good!



Footnote 1: Vol.20 No.11 of Stereophile, p.177

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