Listening #99

That was called "love" for the workers in song;
probably still is, for those of them left.
—Leonard Cohen

It started around 1950, as postwar economies boomed and commercial radio stations multiplied like bunnies: Broadcasters needed reliable, high-quality turntables, so Garrard Engineering and Manufacturing—an offshoot of Garrard & Co., England's first Crown Jeweler—took up the challenge. They brought their considerable engineering talent to bear on a new design, invested in the personnel and facilities required to make the thing, and released the model 301 motor unit in 1953. It was a huge success—and, strangely enough, it still is.

Edmund W. Mortimer, the man who designed the Garrard 301, came up with some dandy ideas. He created a switching system that all but guaranteed that the rubber idler wheel would contact the platter only when needed, thus prolonging the wheel's useful life. He made it easy for users to keep the main bearing lubricated (true of both bearings used during the 301's commercial lifespan: the grease bearing that was originally fitted and the oil bearing that replaced it). Perhaps best of all, Mortimer made sure that all component parts were durably finished (tropicalised was the delightful term still used in an England fresh from colonizing much of Africa and the Indies). The reader who doubts the need for such a thing is reminded of the photo comparison in last month's "Listening" column, showing a 54-year-old Garrard 301 bearing alongside that of a 23-year-old Linn LP12.

But there's one thing E.W. Mortimer apparently didn't foresee: a world in which his company's flagship product would never be equaled, let alone bested, more than a half-century after its introduction. Move over, Peter J. Walker and Leo Fender.

Flat is bad
So it was I long lusted for a Garrard 301 of my own; so it is I owe a debt of gratitude to retired engineer George R. Koonce, whose generosity made it happen at last. (The full story of this also began in the February issue.)

By the end of the first phase of its restoration, my 1957 Garrard 301 had a new bearing gasket and a couple of new idler-retractor springs; more to the point, it had also had a thorough cleaning and lubrication. After all that, its performance was extraordinary, but still limited by its original budget plinth: There remained a considerable degree of audible rumble. Since bearing noise and motor noise are conducted through the 301's cast-aluminum chassis—the motor noise somewhat less so, given that it's suspended from the rest of the works—one's plinth must provide for that chassis a means of draining off those noises rather than storing them or reflecting them back into the working bits.

Thus, to me, an appropriately massive structure seemed in order, but one neither too lossy nor too dense and reflective. Assuming that wood is the easiest material for most hobbyists to use, it also seemed to me that plywood best fulfills those requirements. It also seemed reasonable to avoid the addition of damping material (if my assumptions were wrong, it would have been easier to add damping at a later date than to take away), and to pare away only enough mass to accommodate the works of the motor unit itself (another assumption more easily fixed at a later date). Thus, as Frederick Douglass might have said in another time and place: laminate, laminate, laminate.

Step one was thus a trip to the lumber store: a less daunting experience today than even 10 years ago, thanks to the proliferation of such retailers as Lowe's and Home Depot. Both chains sell precisely cut 2' by 2' plywood project boards in various thicknesses: ideal for the amateur woodworker who lacks either the table saw or the suitably capacious car or truck needed to deal with standard 4' by 8' sheets of the stuff. I selected seven birch-ply project boards, three of which were ½" thick and four of which were ¾" thick. (Total materials expenditure: $59.24 plus tax.) I guessed, perhaps dumbly, that it would be favorable for vibrations generated by the Garrard motor unit to first enter and excite the thinnest sheets before progressing toward the thicker sheets, from whence, I hoped, they were unlikely to return.

For similar reasons—ie, the desire to conduct rather than damp or reflect unwanted energy—I decided to use only animal-hide glue (which I see was also chosen by my favorite bloggers on the subject). For a detailed explanation of the benefits of hide glue, which has more in common with Elsie the Cow than most gourmands might care to consider, I humbly recommend a piece I wrote on the subject for the Spring 2009 issue of The Fretboard Journal (). Briefly, hide glue dries to a less gummy and more crystalline structure than the far more common yellow glue (aliphatic resin), and works more as an energy transmitter than as a gasket between different wooden parts—hence its popularity among the best luthiers. On the downside, hide glue must be kept warm during use (even, ideally, the pre-bottled Titebond hide glue, the stabilizers in which tend to diminish some of its benefits); it sets rather quickly, severely limiting the amount of time during which the user can adjust the fit of his parts; and it smells funny.


volvic's picture

What a brilliant article! Really enjoyed the Feb edition as well as this one.

OneMic's picture

Bang up job on that table! I am revving up my table saw in anticipation that I can get my hands on one of these jems.

robertbadcock's picture

Seeing the concept of a plinth broken down like that; or rather seeing it constructed like that... I feel like I've been reading/viewing post-grad philosophy material.

Outstanding stuff; and big kudos for doing the work yourself... so few can actually craft anymore.


V96GLF's picture

What a fascinating project, very well executed!

I had a 301 in the 70s, when I was a budget-constrained student. I paid £10 for it!

My plinth was a single piece of plywood, supported by a fiberglass base. I had a summer job in a fiberglass factory, so that part was easy enough to have manufactured at zero cost to me.

Yes, it rumbled! But what I discovered was that the rumble was coming from mechanical transmission through the plinth to the tone-arm. I solved it by removing the turntable-to-plinth bolts, and instead resting the turntable on foam pads. The foam I used was the type used for bicycle handlebar padding (I happened to have some offcuts). Pipe lagging foam has a similar density, and would probably also work.

In addition I used the fairly well-known trick of wiring a light bulb in series with the motor, to reduce the motor torque. Experimentation is required, but I think I ended up with a 60W tungsten light bulb.

With these two fixes in place, the rumble was cured.

Stupidly, I got rid of the turntable about 20 years ago, when it seemed that vinyl was dead. What a fool! I wish I could have it back, but I doubt I’ll find another for £10.