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Positive Feedback ISSUE 23
january/february
2006

 

walker audio

Impressions: The Walker Audio Proscenium Gold Signature Turntable System, a Photo Essay, Reflective Digression, & Review - Page 4

as reviewed by David Robinson

All images and image processing by Robinson; drawings by Bruce Walker & Dan Zimmerman

 

 

 

After the stylus was dialed in, Lloyd went to work calibrating the phono amp with a Digital Multi-Meter (DMM). The DMM, which comes with the Reference Phono Amp, is plugged into the output jack and allows a user to find the null point with real precision. Lloyd and Fred didn't even have to listen to the phono amp; all they had to do was monitor the DMM, which they did at a distance of three to four feet, to minimize the proximity effect. If the phono amp is picking up significant radio frequency (RF) signals, it will show up here; they are looking for a stable "0" reading at the marked scale of the DMM. Given the highly "naked" nature of the Proscenium signal path, it is vulnerable to outside interference.

As it turns out, we were picking up a lot of RF, due to the fact that my listening room is on a major hillside at an elevation of 650'—which means that our line of sight to just about every RF source is superb. This is great for radio, TV and HDTV broadcast reception; rotten for bare silver wire and highly sensitive phono amps like the Walker Reference. Fortunately, Lloyd and Fred had the answer for this problem, as you'll see.

The completed installation—looks great, but what to do about that RF in the phono section?

Fred and Lloyd went back down to the garage with the tonearm, and proceeded to re-build the bare silver tonearm wire. What they did was to create two twisted pairs of phono cables by wrapping them by hand. The principle is the same one used in telephone cables (CAT1-3) and unshielded twisted pair (UTP) Ethernet cables (CAT5/CAT5e/CAT6): by twisting pairs in an unshielded line, you attenuate outside interference by creating a local magnetic field powered by the signal current. Result: your signal passes, outside RF bounces.

Here Lloyd prepares to finish the far end of one of the new twisted phono leads; Fred holds the tonearm and the MC end of the cable in place while Dr. Lloyd performs delicate surgery.

Having completed the new twisted pairs, Lloyd prepares to attach the leads to the Magic Diamond cartridge. You can see the access hole for the cables on the bottom side of the Proscenium carbon fiber tonearm.

Having completed the re-wire, Lloyd and Fred re-installed the tonearm on the Proscenium for re-testing and calibration of the phono amp.

Lloyd re-connecting the phono leads and preparing to attach the ground wires, while Fred holds the tonearm in place above the damping trough.

Lloyd and Fred re-checked the re-wired phono leads and the phono amp one more time, just to be sure that we were getting a proper null and correct calibration. Lloyd is out of the picture to the right, reading the DMM display from a distance to avoid any proximity effect.

A side view of the Proscenium turntable, the clear gap between the Prologue Shelf and the Prologue Rack, the leads, the grounding array (all silver wire), and the DMM in place. The yellow-handled hex driver is the VTA adjustment tool.

In this photograph, Fred is checking the tracking force with a digital stylus scale borrowed from Jennifer Crock of JENA Labs. The tracking force adjustment is found on the far end of the guide bar, and is easily altered for the smallest increments. You can see the cueing bar in this image, and also the damping pin under the guide bar.

The next step was to make sure that the turntable speed setting was spot-on. The Proscenium system also comes with a KAB Electro-Acoustics strobe disc and strobe light, and a set of instructions for using it. With this handy-dandy system, Fred was able to adjust the Walker Audio Ultimate Motor Controller until the speed was calibrated for both 33 and 45 RPM.

Meanwhile, back at the ranch, Lloyd was applying Walker Audio's Extreme Super Silver Treatment (E-SST) to the pins of the Omega Mikro Active power cords. Here we see proper technique for applying E-SST: you put it on SPARINGLY, razor thin, and NOT GOBBED ON WITH A SHOVEL.

Enough said.

Yet another "at last!" moment: firing up the Magic Diamond for the first time!

It was finally time to try the whole thing. Lloyd added some synthetic oil to the damping trough, and did some preliminary adjustments of the oil level on the damping ping. An initial trial VTA was set, and the Proscenium's coated brass record clamp came down over my 180 gram pressing of Scheherazade on Classic Records reissue of the LSC. Lloyd used a carbon fiber brush (supplied with the Proscenium) on the LP, and then lightly brushed the record clamp and the tonearm to neutralize any static build up. This was a dry run…no serious listening yet…but the air pump, motor drive, and all mechanical parts were working correctly, right out of the box.

Now that they knew the Proscenium was operational, Lloyd and Fred turned to completing the cabling of the rest of the playback system. In this image Lloyd is testing the Omega Mikro Active ribbon interconnects for continuity. The copper battery pack leads that supply 18 Volts to the sheathing are visible at the bottom center of the photograph.

Here you can see a close-up of the Omega Mikro's ribbon and sheathing protector at the RCA end attached to the output of the Walker Audio Reference Phono Amp. The Omega Mikro cables require very careful handling, but produce spectacular results. You won't be able to have pets, children, or clumsy friends in your listening room if you have the Omega's in place—but you will hear the most transparent, crystalline sound that your system will produce. The Omega Mikro cables and power cords knocked me out completely. If you can provide the care and environment they require, you'll be re-paid many times over in audio revelations.

If you can't, though, then you should find something more robust…the Omega Mikro's are definitely not for the faint-of-heart, or the bumptious of household. Lloyd Walker recommends the Silent Source power cords, interconnects and speaker cables as excellent alternatives.

Towards the end of the setup session, PFO's Mike Lavigne dropped in from Seattle. The owner of a Rockport System III Sirius (the big guy) turntable, Mike has an abiding interest in fine turntables and analog playback, though he also enjoys his EMM Labs CDSD/DAC6 SACD front end. (For a profile of his listening room, see Mike's photo essay in PFO Issue 16 at https://positive-feedback.com/Issue16/lavigneroom.htm.) Mike followed the final stages of cabling and configuration with close attention.

Here's the Walker Audio Reference Phono Amp with the wiring complete, the grounding in, and the Omega Mikro Active output interconnects in place. These were run to the inputs of the Linn Klimax reference stereo line preamp two shelves down. From there, it went to the darTZeel NHB-108, then on to the Kharma Grande Ceramiques. Our initial quickie trials indicated that the playback chain was operational …we could heat things up now.

Maestro Lloyd adds some synthetic motor oil to the damping trough, getting its level just right before doing some listening with members of the PFO group. Lloyd uses synthetic oil because it does a fine job of knocking down vibrations, is easy to obtain, and doesn't have the smell that standard oils have. I checked this carefully …unless I put my nose within an inch or two, I can't smell the stuff at all. And boy, does the Proscenium's damping system work.

While members of the PFO group arrived (Rick Gardner, Jennifer Crock, Michael Crock, and Mike Lavigne), Lloyd finished dialing in damping. You can tell what a tough crowd this is—check out the smile on Lloyd's face!

Lloyd gave an overview of his turntable system to (left to right) Jennifer Crock, Michael Crock, Rick Gardner and Mike Lavigne.

Having completed the introduction, Lloyd queued up an LP. Into the groove went the Magic Diamond; out of the groove came—MAGIC. (See Rick Gardner's quick retrospective sidebar about this section elsewhere in this issue.) You have to remember that the Proscenium was brand spanking new and without any serious break-in. You've seen the assembly in this photo essay; the major work was all done within 24 hours. And here we were, listening to the results at the end of the same day that assembly had begun. All of us were various shades of amazed and pleased at the very first results from the Proscenium system. We played some classical (RCA Living Stereo reissues via Classic Records), and some rock (e.g., the Japanese pressing of Led Zeppelin II, and the Classic Records 180 gram 33.3 RPM of David Crosby's If I Could Only Remember My Name …the song "Laughing.") Side one of this album is a particular favorite for both Rick Gardner and me; the music is truly haunting.

I'll never forget the look on Rick's face when "Laughing" finished, and we got ready to go to dinner. He sat there for a moment, then stood up, shuddered, looked at me and said, "Unquestionably the finest sound that I've heard in your system."

Coming from Rick, this is saying quite a lot. And frankly, I'd agree.

Another look at the damping trough after it settled in; the wire is a naked silver grounding strap.

The following morning, Fred and Lloyd checked the Proscenium again for any signs of settling or drift. (They didn't expect to see any.) All was well. In this image, Fred is assessing the stylus alignment one last time.

Lloyd does a final KAB calibration strobe check of the turntable speed.

Lloyd packs up the leftover parts and pieces.

Valid Points tuning discs were even carefully placed on the Kharma Grande Ceramiques.

Lloyd and Fred doing final layout and tape-down of the Omega Mikro Active speaker cables.

Attaching the Omega Mikro Active speaker cables to the Kharma.

One set complete; after this, Fred and Lloyd worked to elevate all cables off the carpeting, to avoid dielectric effects.

Left channel tape-down. Lloyd and Fred are thorough in every phase of their work. "The devil's in the details," says the Lloydmeister—I don't think you can argue with the sonic results.

Another look at the left channel area, showing the neat array of cords, cables, tubes, and stands. Pleasing to the eye, but even more pleasing to the ear.

Job done! Lloyd and Fred enjoy the moment of completing the Proscenium Gold Signature system setup; they had to take off early the next day.

IMPORTANT NOTE: the purchase of a Walker Audio Proscenium system now includes the cost of Lloyd Walker and Fred Law personally setting up and optimizing the system, as they did for me.

The beauty of the Proscenium as a work of art is undeniable…

…and there is no doubt in my mind that you are looking at a pinnacle of the audio arts.

Page 5 Extended notes on the Proscenium Gold Signature system

 

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