Listening #159 Page 2

We began our listening with a borrowed sample of the Hommage T1, which had been in my system for a few months, and which had impressed me all the way to hell and back. The T1 was my favorite, and I made no secret of it. Sure enough, the T1-fueled system sounded great that day. But before moving on to a different trannie, I had to leave the house for a short while and collect my daughter at school. I returned home about 20 minutes later, and my visitor and I decided to spin one more record before making any changes.

My system now sounded like shit: pinched highs, no texture, a compete lack of flow and momentum.

That was an easy act to follow—and, indeed, with a new phono transformer installed and used in place of the Hommage T1, the system sounded much better. But it still didn't sound as wonderful as it had earlier in the day.

Then and there, I knew what had happened, just as I knew it was something I could never prove: Whether out of curiosity or competitive mischief (in the years since, I have been given numerous reasons to suspect the latter), my visitor had almost certainly used his multitester on the coils of the T1—and thus magnetized the cores. I knew it because I had once, out of ignorance, done the same thing to a different phono transformer, and had heard precisely the same results, which lasted for nearly a week. Indeed, the T1, too, began to sound better after a few days; my feelings toward my visitor have taken considerably longer to improve.

This may be germane because the output jacks of my preamplifier are wired directly to a pair of internal output transformers. (This is one of the things that makes the Masseto so special: It's the least expensive Shindo preamplifier so equipped.) For that reason—and perhaps because there remain step-up transformers at my preamp's input stage, not to mention transformers in the output stages of all my amplifiers—I wonder if my system, and others like it, simply are the least apt candidates for magnetic conduction . . . ?

No one who has heard the sonic consequences could fail to agree: Magnetizing the coils of a signal-carrying transformer is to be avoided at all costs. Perhaps magnetizing other conductors in an audio system, done with precision, is a better idea—but how does one get the magnetism to stop when it encounters a transformer? Take a detour around it and resume on the other side? I have no idea.

A video posted on the High Fidelity Cables website states that "your music system is one big magnet." In the sense that an audio system crawls with electromagnetic energy, owing to a preponderance of AC currents, I suppose there's some truth in that; for the sense apparently intended—the same video also says that "magnets make music" and suggests that adding more magnets makes more music—I think the ground is a bit shakier. As with virtually everything else I've learned about domestic audio, there are few universal tweaks, just as there are few universal playback technologies: HFC's ideas and products may indeed have merit, despite their lack of suitability to my playback system; I look forward to hearing what others have to say.

Woodsong Audio's Eddy-Current Brake Disc for the Garrard 301 and 401
A while back, I began corresponding with a woodworker and phono enthusiast named Chris Harban, who builds some of the most head-turningly beautiful turntable plinths I've seen. Working from a factory space in Sandpoint, Idaho, and doing business under the name Woodsong Audio (footnote 4), Harban makes plinths primarily for the Linn LP12, Garrard 301 and 401, and Thorens TD 124, with other types available. He offers a big selection of hardwoods and veneers, and his LP12 plinths in particular are made to spec—by which I mean that Harban doesn't second-guess or attempt to "improve" on Linn's proven designs, and he assures the buyer a precise fit for mechanicals and electronics alike, to the thousandth of an inch.

Woodsong has also branched out (sorry) into the refurbishing of used Garrard 301 and 401 motor units; it was with those products in mind that Harban and I began, about a year and a half ago, to toss around the idea of my reviewing a complete Woodsong 301, and comparing it with the 301 that I acquired and refurbished for myself, and for which I made a publicity-hungry plinth of my own. Of course, Woodsong, like so many small manufacturing companies, must satisfy paying customers to stay alive; understandably, there has not yet been enough time to complete a project for which no one will immediately pay (although Harban reports that he's getting close, and that the review sample will some day become reality). In the meantime, Harban decided to satisfy his own needs and those of DIYers by manufacturing something the Garrard 301/401 community has long needed: a modern, high-quality replacement for the motor unit's eddy-current brake disc.

The component in question is a two-part thing: an aluminum-alloy disc 0.08" thick and just over 3" in diameter, to which a 0.5" bronze hub/collet is press-fitted. Three very small grub screws in the collet secure this disc to the motor shaft, where it rides just above the body of the motor and just below its pulley. Off to one side of the motor is an odd-looking mechanism about 1½" long, with an oblong magnet—again with the magnets!—held between two flat strips made of a cadmium alloy. That's the brake itself, and it pivots in response to the chassis-mounted speed-adjustment knob, describing an arc of perhaps 50¯; when the adjustment knob is set for the highest speed, the brake is completely clear of the disc; but as the knob is turned toward the slow end of its range, the brake rotates toward the center of the disc, and the "calipers" formed by those two metal strips enclose an ever greater area of the disc—not making contact, but using magnetically induced eddy currents to impede and slow the disc, and thus the motor and, ultimately, the platter itself.

It sounds so simple that one might wonder, Why should you ever need to replace such a thing? First of all, although the brake and the disc aren't supposed to make contact, they sometimes do, especially if the disc's height on the motor spindle is misadjusted—I don't know precisely how much clearance there is between those cadmium-alloy strips and the upper and lower surfaces of the brake disc, but it ain't much—and the edges of the soft-alloy disc get banged up, making clearance (and balance) more difficult to attain. Second, these discs weren't always terribly well made to begin with, a realization that brings with it the possibility of better performance from better machining. Finally, although the original disc is made with three round openings near its hub, intended as access holes for lubricating the armature bushing just underneath, they're inadequate in ways that are apparent only to those who've attempted such a thing.

Woodsong Audio's hopefully better eddy-brake disc ($280) is made of an aluminum alloy said to be identical in conductivity to the original, but with a hub made not of bronze but of 6061-T6 aluminum, chosen for the strength and durability necessary in a part with four grub screws (vs the original's three). The seam between disc and hub is so difficult to detect that, at first glance, I thought the Woodsong disc was machined, in its entirety, from a single hunk of the same metal. Chris Harban corrected that mistake, but declined to describe in detail the actual manufacturing process; suffice it to say he promotes his disc as exhibiting far better balance than the original, the hub of which was installed in the same manner as a rivet (ie, with less than the highest degree of precision).

A nice added touch: The Woodsong disc also incorporates a trio of openings intended to ease motor lubrication, but these are machined at an angle relative to the armature, thus allowing the user to get the tip of his or her dropper or applicator that much closer to the motor bushing.

The Woodsong disc is protected during shipping by thin, flexible vinyl sheets, top and bottom; these are peeled away during installation—which, thanks to the excellent instructions, was straightforward and without tragedy. (Notwithstanding the new disc's nicely angled lubrication holes, I took advantage of the opportunity for an even easier lube job after I'd removed the old disc but had not yet installed the new.) Your $280 also buys the necessary Allen wrench, shims for adjusting disc height, a tiny vial of motor lubricant, and extremely nice, professional-looking packaging. In all, the Woodsong eddy-brake disc is clearly the product of someone whose level of attention to detail borders on the obsessive: an excellent characteristic in this line of work.

Before I rang out the old and rang in the new, I used my Dr. Feickert Analogue Adjust+ 7" test record and my iPhone copy of Feickert's PlatterSpeed software to measure my Garrard 301's speed stability, and the results were as unpretty as Claire Danes coming off a weeklong crying jag: Although wow wasn't bad—0.12% using the 2-Sigma method, 0.11% using the dynamic method—the maximum deviation in raw frequency was –19.1/+9.1Hz. Ouch!

With the Woodsong brake disc, wow was almost the same, but speed fluctuations decreased slightly, to –17.1/+9.6Hz. Well!

Obviously, something else is rotten in Swindon, and I think I know what it is: Lately I've noticed a bit of slop between the upper and lower bearing shafts of my 301's idler wheel and the bronze bushings in which they fit—and I suspect the bushings more than the shafts, partly out of pessimism, as the latter will be less easily replaced than the former. That said, Chris Harban has announced that he is working on a precision-machined replacement for the 301's idler-wheel carrier, to be fitted with bearings of reportedly greater precision. My experience with the very beautiful and recommendable Woodsong Audio eddy-brake disc encourages optimism, even as I suspect I'm in for a wait.


Footnote 4: Woodsong Audio, 71 Gooby Road, Suite B, Sandpoint, ID 83864. Tel: (208) 304-0973. Web: www.woodsongaudio.com.
ARTICLE CONTENTS

COMMENTS
ddraudt's picture

Thanks Art for you article on High Fidelity adapter .
So Sorry you were not aware of the break in time for magnetic products.
All of Ricks magnetic products require a few weeks to a month to sound their best.
They can sometimes sound bad at first so it takes patience.
With proper break in, the HF full loom My friends and I have create the most
"Live" sound I've ever experienced or imagined.
Seems like you had fun saying bad things. Too bad you missed something so spectacular by not being properly informed and prepared.

Art Dudley's picture

>All of Ricks magnetic products require a few weeks to a month to sound their best.

You have a good imagination.

>Seems like you had fun saying bad things.

Correction: You have a great imagination.

ddraudt's picture

Thank you Art! lucky me! I have Great imagination, great hearing and more knowledge and experience in audio. But this is off point my friend, I was simply trying to point out you're missing critical information about a product you were reviewing.

Cheers

Jason Victor Serinus's picture

If a product truly takes a month to break in - 720 hours, to be precise - which would necessitate tying up a reviewer's system for that long, then it is reasonable to expect that the manufacturer would, at the least, explain this to the reviewer, and, if they really thought the matter through, also offer to do the break-in before submission.

Martern Aller Arten's picture

Being fully aware many products require "break in" time to reach maximum performance, I question this product, simply because there are no moving parts involved, or complex circuitry. If the magnets need to be charged, why doesn't the company send them ready for use? Tesla doesn't sell new cars with dead batteries.

AJ's picture

Only buy (well) used. Never new.
Problem solved ;-)

Geardaddy's picture

Art, it does not hurt to try and see if time changes your perceptions. You liked what you heard with the SS room, and Robert and SS know good sound and would not ally themselves with Rick if he did not do the same....

xyzip's picture

Maybe I'm so simple that *a picture* biases me toward an electro-magnetic device, but I can't help but mention this.

Dudley's assessment of the changes in sound, noticeable and reliably repeatable-- 'duller, less contrasty, midrange-prominent'-- reminded me of something.

Maybe the picture put it in the back of my mind, and maybe it doesn't correlate at all, but those aspects remind me of what you get when you have some redundant adaptor-- some y-adaptor or right-angle thing, inevitably made of brass or pot-metal & then plated or powdercoated-- that is in the signal chain of your system. Remove it, and you reverse the effects; what was a little duller, a little rounded or pace-degrading-- mysteriously disappears.

(Generally it happens when you're trying something out, a new component with different kinds of connectors or something, or you want to split a signal for sub/main or similar. Regardless, you forget to remove the now-useless set of pot-metal "pads" beyond the timeframe of your experiment, and your sound stays thick and dull till you remember.)

Just a stray thought there, of course. But worth noting that whatever else, whatever magnetic magic is or isn't happening, the installation of those (powdercoated base metal) tubes in the picture-- is unavoidably an example of this selfsame thesis: that the addition of powdercoated base metal tubes in the signal path generally sounds worse. Thicker and duller.

Oh and the other thesis is that if you change anything, you hear *some* change.
I'd vote for my versions before the 720-hour rule, but hey, we're all partial to our own theories.

JD.

trynberg's picture

Really, break in? Magnets break in? That's news to physicists everywhere...

The old skin effect snake oil again, eh? Skin effect doesn't occur anywhere near audible frequencies in any reasonably designed cable (or poorly designed one for that matter).

klosterman's picture

If they need weeks of break in, that should have been emphasized from the supplier. Moreover, if that is the case, send Art well used items instead of brand new.

Related pet peeve: when I read show reports that indicate the exhibitor brought brand new products, I'm stumped. Breaking in your own products at a show? Is that the best place to be doing that?

X