SYNERGETIC SPINNER
From a purely musical viewpoint, the vinyl LP is still the "mother lode," a repository of great music, of music familiar and music obscure and esoteric. A great amount of this music may never be recorded anew or transferred to CD. To make it short, my interest in state-of-the-art record players is in mining the vinyl treasure vein and optimally enjoying the great music inscribed in record grooves.
John Bicht heads up Versa Dynamics and is the engineer and designer of the extraordinary Model 2.0 record playing system. He is a man of many parts, with impressive credentials in the audio field and in high-tech mechanical engineering. Bicht lived in England for some years and, among other things, was responsible for the highly regarded Mission 774 LC pickup arm and subsequently helped in the development of several Mission loudspeaker models. He devoted 18 months of original research to an innovative turntable design that incorporated many novel features.
Temporarily disenchanted with the hi-fi business, Bicht got involved with the development of such diverse mechanical engineering devices as an electric taxi and an emergency exit door for the Hong Kong subway trains.
About four years ago, he set up Versa Dynamics in Warminster, Pa. and began the research that culminated in his Model 2.0 record-playing system.
When Bicht installed the 2.0 in my audio system, we had a chance to discuss his design philosophies and to critique some well-known turntables.
We got along famously because we quickly found ourselves in total agreement on one cardinal point: That in all audio equipment, but most especially in record players, spurious and unwanted resonances are the deadly, implacable, omnipresent enemy of good sound quality. Thus, it came as no surprise that the suppression or elimination of resonant coloration was Bicht's overriding consideration in designing the 2.0 player.
The Model 2.0 is indeed an integral system, with three major components working together synergetically. These three parts are an air-bearing turntable and an air-bearing, lateral-tracking pickup arm; a control box fitted with electronic circuitry and pneumatic elements, and an air-compressor unit.
The main structure of the turntable chassis is made of a laminate of end grain balsa wood and aluminum sheet.
A pair of the laminated structures are bonded to each other, with a sheet of a high-hysteresis polymer between them, and this provides constrained layer anti-resonant damping. The entire turntable chassis is treated for six hours in an industrial oven, in four separate operations, each using different epoxy adhesives. The result is an inert chassis of great rigidity.
The turntable platter is also a laminate, of cast aluminum with an acrylic top plate, with constrained-layer damping. When struck with a fingernail or pencil, this very inert platter does not exhibit ringing.
One of the most novel features of the 2.0, and a major contribution to its high performance, is a precision air bearing. This bearing is similar to that used in inertial navigation satellites, and it is quite large, being 4 inches in diameter.
High-pressure air (about 28 psi) and pre-loading vacuum for stabilization are fed to the bearing from a quarter horsepower remote compressor! This type of air bearing has immense rigidity, with a stiffness in all directions exceeding 100,000 pounds to the inch. It also is critically damped in all axes, helping prevent fundamental platter resonances. Incredibly, the operating clearances on this air bearing are 250 millionths of an inch! Low-level vacuum is ported through the bearing, to inner and outer gaskets on the turntable platter, to provide record hold-down. While vacuum holddown is a significant help in reducing resonant coloration, studies have shown that even with a low-level vacuum, dust particles can be imbedded in the surface of the record in contact with the hard platter, thus causing impulse noises. Therefore, the 2.0 has a novel dust-imbedment mat, made of a proprietary material that has a very low yield strength. Dust particles up to 0.01 inch (about two or three times thicker than a human hair) are imbedded in the mat rather than in the PVC of the record. At the same time, the mat's high modulus of elasticity prevents resonance and vibration in the record.
A 400-pole motor is rigidly attached to the turntable chassis, with the platter driven via a flexible urethane belt. The motor is driven by a proprietary microprocessor-governed synchronous system, and motor speed is independent of line frequency since its signal is derived from a quartz crystal. Motor wires and air hoses extend through the chassis base in a 6-foot umbilical cord which connects to the control box.
In the 2.0's air-bearing lateral-tracking arm, the design goal was again the elimination of resonances. The typical low-frequency resonance is avoided by using a stubby arm structure shorter than 3 inches. Thick wall construction in the arm and magnesium headshell reduces high-frequency resonances. The arm is connected to a high-pressure air bearing, and 45 pounds of air are supplied to the bearing from the compressor. While the air bearing has near-zero friction and is free to rotate and slide along a precision-machined shaft, it has enormous rigidity. It is also critically damped radially, with the headshell and headshell mount precision lapped to provide rigid coupling. The entire arm structure swings forward 90° to a magnetic stop to allow record changes. It then is pushed back to the playback position, where it encounters a very powerful neodymium magnet to hold it rigidly in place. Cueing of the arm is via a manual lever. Easy-to-perform adjustments are provided in the arm for height, VTA, cartridge tilt, tangency, and tracking force. For these adjustments, no alignment gauge is needed other than a tracking-force gauge. All signal wires are van den Hul silver. Gold-plated RCA phono connectors and a five-way ground connector are provided on a plate at the rear of the base plate.
The chassis/turntable/arm is isolated from structure-borne vibration and feedback through a four-coil compression spring system which gives a 2.5 Hz resonant frequency in both lateral and vertical modes.
The front panel of the control box has switches for system power, for 33 1/3 and 45-rpm speed, and for the platter motor and record vacuum. The motor switch handles vacuum via a relay in the remote compressor. This quarter-horsepower compressor is a heavy-duty professional unit and must be remotely located; thus, 50 feet of air and vacuum hose are supplied. A noise-reducing enclosure greatly reduces compressor noise, and shock mounting of the entire compressor unit reduces floor vibration.
A black-lacquer turntable enclosure is standard, with rosewood and teak as options. The turntable unit measures 18 1/2 inches wide x 17 5/8 inches deep x 9 1/4 inches high, the control box is 6 x 17 x 4 inches, and the compressor is 22 3/4 x 10 7/8 x 12 7/8 inches. In spite of its complexity, the Model 2.0 can be assembled quite easily, and the turntable and arm are supplied mounted on the chassis/base. So, it is really just a matter of connecting wires and hoses, mounting the phono cartridge, and then making adjustments.
Mounting the phono cartridge is quite straightforward, and the various adjustments are user-friendly. The VTA adjustment is simple to execute and can be made during playback.
With the 2.0, I used the Cello Chorale moving-coil phono cartridge, the Ortofon MC3000 moving-coil cartridge with its companion transformer, and the Shure Ultra 500 moving-magnet cartridge. Cello cables connected the output of the turntable to the MM and MC modules in the Cello Audio Suite preamplifier, to the Cello Performance amplifiers, and to the Duntech Sovereign loudspeakers.
The Versa Dynamics 2.0 simply exudes "high tech"--even when you're just looking at it-and its performance is fully up to its appearance. Now, I've had quite a number of pretty fancy and expensive pieces of record playback equipment over the years. I thought that certain combinations gave me the best sound one could expect from a vinyl LP. However, in terms of degree of fidelity, accurate retrieval of recorded information, and newly revealed "musicality," the 2.0 quite simply exceeds by a wide margin anything have ever used. I believe that the principal reason why records sounded so dramatically cleaner, more open, and transparent, so much closer to the music when played on the Model 2.0, is Bicht's almost obsessive attention to the suppression and elimination of resonances. He has addressed them in the suspension, the platter, the chassis, the arm, the headshell, and even in the record itself. And while his vacuum hold-down system also helps alleviate resonance problems, he has ensured that it does not itself cause ticks and pops by imbedding dirt in the record's undersides during play; his clever dust-imbedment mat, I assure you, works as claimed! So much sonic "sludge" is gone in playback with this system that what is left is just the "sound" of various phono cartridges. In other words, if an MC cartridge has a resonant peak in the high frequencies or another cartridge is bass-shy, whatever its characteristics, you'll be able 'to discern them "loud and clear" and with nothing camouflaged by an overlay of resonances.
Whether an MC or MM phono cartridge is used, tracking is quite precise at the stipulated stylus tracking force. Of course, if a record is badly overcut, even the 2.0 can't rectify that! I played LPs from the earliest days. I still have a lot of the original Mercury discs engineered by Bob Fine. All I listened to were revelatory experiences in terms of resolution, bass response, cleanness of sound, and dynamic range. Some of the most striking sound, however, was produced by direct-to-disc material from Sheffield and my own recordings for Crystal Clear.
Fortunately, on a number of my recordings I have either tape masters or first generation copies of them, so I was able to compare the LPs with the tapes. Although I still preferred the tapes, mostly for their superior dynamic range, the discs made from these tapes were very nearly their sonic mirror when played on the 2.0. Perhaps the most convincing experience was when I played some recent state-of-the-art Direct Metal Mastered discs from Teldec. While I greatly admire this brilliant advance in disc technology, I have felt that they sounded a little too bright. Played on the Model 2.0, the DMM recordings were magical-no brightness or high-frequency exaggeration, just the cleanest, quietest, most musical sound I've ever heard from a vinyl record! This ultimate expression of high-tech record playback doesn't come cheap.
At $11,500, the 2.0 system is not going to set sales records. Also, it is not likely to appear in most dealers' showrooms, so you might write to Versa Dynamics ( P.O. Box 3062, Warminster, Pa. 18974) if you want more information.
Understandably, however, the 2.0 will find appreciative customers in the professional audio world and in the laboratories of record companies.
(adapted from Audio magazine, Jul. 1988; Bert Whyte)
= = = =