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page date: 11/7/06

James O'Donnell's Russco Mark V

Here is the shortest possible version of my Russco Mark V story!

As luck would have it, while digging through a "junk room" of a radio station near me I came upon a Russco Mark V Vari-Speed Broadcast/Deluxe turntable in excellent condition. I was not looking for another turntable (I had recently finished restoring a Thorens TD 150 MkII), but it really had just dropped into my lap--and at my wife’s insistence (!) I dragged it home for a trial. After putting it on some 1X6 pine legs, a cursory cleaning/lubrication, and installing a throw-away cartridge, I was astounded by how it sounded. Inspired by reading about successful idler restoration projects done by others I decided it could be worth my time to restore and plinth it.

My good fortune continued. Through an occasional poster on the Vinyl Asylum site I generously received an owner’s manual that also included complete schematics and servicing information for the turntable’s mechanical and electrical components. I was amazed at the build quality and forethought—it appears that every aspect of the Mark V was engineered to be serviceable (or even rebuilt). So I went through the manual item by item, intending to do whatever was necessary to bring it back to NOS condition, mechanically speaking at least.

The things I did upon studying the manual included replacing the idler wheel and belt (I experimented with o-rings of different sizes and materials when replacing the original cracked belt); taking the motor off and cleaning/lubricating all the bits associated with it; experimenting with bearing lubricants; experimenting with dampening and different mats and mat combinations, and spending a couple of hours adjusting motor phase etc. via pots in the servo control unit and a stethoscope. I also experimented with armboard materials, making armboards from pieces of walnut, cherry, and maple as well as laminated ones. The best sounding was a birch plywood armboard which I additionally veneered top and bottom with tiger anigre. All of these tasks took place one item at a time, listening after each project while the turntable was mounted on its pine stilts, before I considered plinth designs.

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After much hand-wringing and probably a dozen sketches I decided to make a "Loricraft style" plinth, out of hardwood. I also wanted the design to provide a visual foil to the industrial look of the TT so I went with a frame-and-panel construction mostly with Pennsylvania black cherry and some ("real," and very old) mahogany that I have. The unseen corner blocks etc. inside of the plinth are maple and walnut. The panels" in the frame float in their openings and do not vibrate against the frame members.

I also spent a number of evenings experimenting with various combinations of spikes, pads, and platforms, finally settling on the simplest solution of just plain spikes.

Does the turntable sound better now than when it had an aluminum armboard, and when it was sitting on pine stilts? Yes! It is so much better than my beloved Thorens TD150 MkII that it took a few evenings of A-B listening for me to believe how much better it is. The Russco throws a soundstage that is subjectively 30-40% wider-taller-deeper than the Thorens, yet the soundstage does not sound the least bit hollow or unsorted. It is a very musical presentation with rock-solid PRaT and wonderful bass response, yet delicate and very precise in the way that it images within a dense orchestral texture (about 80-90% of my listening is with orchestral repertoire). I have no sense of rumble when listening, so I guess that my good luck continued even through the plinth design! Every minute hearing it is a joy for me.

A different arm may or may not be in the turntable’s future (the installed Jelco works very well with the famous HIFI am tweak from the Audiogon forum + a Denon DL103). I’m looking for a NOS AT arm, perhaps a 1009, or another high mass arm from the 70s, but I’m in no hurry.

I didn’t appreciate how few of these Russco Mk V turntables are out there until deep into the project. The story relayed to me was that after several years of R&D the Mark V was the last model produced by Russco as a new flagship, and that it was designed to be the "greatest turntable in the world" with instant starting, electronically controlled variable speed, very low rumble, and rugged enough for continuous use. The drive system is a hybrid "belt isolated capstan rim drive" that accelerates the platter from 0-33.3 rpm in 26 milliseconds (about 1" of spin). Unfortunately for the company the turntable was expensive enough (over $1K in 1979 when it was released, without arm or plinth) that Russco customers continued buying the "lower" model instead. This "swan song" by Russco therefore drained resources and actually contributed to the company’s demise, which led to its later being bought by Rek o Cut.

In closing I can report that the buzz about idler-driven turntables proved true for me. While I appreciate having restored what has turned out to be a rare turntable, I do wish there were more of these Russco Mk V turntables out there--if for no other reason than that restorers could then compare notes like the Garrard restorers have done!