Basis Audio A.J. Conti Transcendence Turntable and SuperArm 12.5 Tonearm

Magnum Opus

Equipment report
Categories:
Turntables,
Tonearms
Basis Audio A.J. Conti Transcendence Turntable and SuperArm 12.5 Tonearm

Technical Description
If you’re familiar with Basis turntables, the Transcendence’s appearance will come as a shock. All previous Basis turntables have been made of acrylic, from the base to the platter, but the Transcendence is made of metal, specifically stainless-steel and two different alloys (one for the platter and another for the base). Despite this fundamental difference, the Transcendence’s structure couldn’t be anything other than a Basis. The foundational design principles and form-factor developed more than 35 years ago are on full display in this new model. The Transcendence introduces fresh ideas, materials, and execution to the same physical principles that guided the development of Basis Audio’s first product, the Debut in 1984. Moreover, as with all other Basis turntables, the Transcendence is totally devoid of bling. Basis turntables are pieces of precision engineering first; any visual appeal they may have springs from the underlying quality rather than from superfluous adornment. Adding unnecessary parts to make the turntable look “impressive” was anathema to A.J. The Transcendence is pure function.

The Transcendence was designed to be a true reference with no sonic or functional limitations. Consequently, the Transcendence can accommodate up to four tonearms of any length. (My review sample was a single ’arm configuration with a Basis SuperArm 12.5.) The Transcendence was also designed to be retrofitted in the field with any future upgrades, including major components such as the platter and motor, without the need to return the ’table to Basis. Even the base can be changed in the field to a larger platform that will accommodate more tonearms. (If you think that you may add additional ’arms in the future it’s best to start with the larger base.) A.J. called the Transcendence the “forever platform” because he believed that it would never become obsolete or be superseded.

The turntable is supplied with the Basis Synchro-Wave power supply and the Vacuum Hold-Down System, both of which have proven themselves over many years. The Synchro-Wave’s toggle switches turn the motor on and off and select the platter’s rotational speed (33 1/3 or 45rpm). The vacuum system consists of a pump that sits behind the rack, a small controller that you’ll need to access when changing records, and the clamp that goes over the spindle and creates an air-tight seal for the vacuum. A pliant lip on the platter mat’s outer edge forms the vacuum seal with the record. The controller has a vacuum on/off switch, a knob for adjusting the amount of vacuum, and a vacuum meter. 

A metal alloy was chosen as the base material for its greater stiffness, improved damping, and ability to accommodate the heavier platter, the massive motor housing, and multiple tonearms. Indeed, the Transcendence weighs 135 pounds (not including the Synchro-Wave power supply or vacuum system). The plater, which Basis calls the Super Platter, is made from a different custom alloy, but both alloys come from the aerospace industry. (A.J. worked as a mechanical engineer in aerospace before founding Basis Audio in 1984.) Compared with acrylic, the alloy platter has greater mass, rigidity, and internal damping for greater speed stability and greater dissipation of record vibration. A machined polymer mat, integral to the platter, forms the interface between the LP and the platter. The mat has four spoke-like channels cut into its surface to direct the vacuum to the LP’s surface. 

Isolation from vibration has always been a high design priority for Basis, a goal taken to a new extreme in the Transcendence. Rather than use pliant springs in damping fluid as in previous Basis turntables, the Transcendence base is supported by four relatively stiff “suspension pods.” The suspension pods are machined from solid blocks of stainless steel, with an intricate constrained-layer damping structure inside. In other Basis turntables, pressing down on the base with your finger causes the base to move and then return to its nominal position once you remove your finger. By contrast, the Transcendence suspension feels absolutely rigid. This ultra-stiff suspension provides a more stable platform for the Transcendence’s much greater weight, while also incorporating new thinking in vibration isolation. 

The AC-synchronous motor is modified with a custom magnet assembly for smoother operation, and then mounted behind the platter in a massive housing machined from solid stainless-steel billet. The motor housing is decoupled from the base with compliant feet. The two motor coils are driven independently by two sinewaves, 90 degrees out of phase, generated by the Syncho-Wave power supply. The two sinewaves driving the motor are independently generated and amplified rather than being created by the more common method of producing a phase-shifted replica of the single signal with a capacitor. This technique contributes to the motor’s smoothness, speed stability, and lack of vibration. Indeed, one can hold the motor in hand and not be able to detect by feel if it is running or not. Basis claims that the Transcendence has lower wow and flutter than any turntable in the world—even direct-drive models—at 0.01%.

The bottom of the massive 3"-thick platter sits more than 2.5" above the base, requiring that the bearing, motor housing, and tonearm support all be of commensurate height. The ability to adjust the platter height relative to the base was a key component of making the Transcendence universally adaptable and upgradable. 

Drive belts are often an afterthought to manufacturers and consumers alike. But to A.J. belts became an obsession. More than 15 years ago he discovered that very tiny thickness variations degraded the sound. The vendor who made Basis belts balked at A.J.’s insistence on tighter tolerances, so A.J. bought all the equipment needed to grind belts and starting making them himself in the Basis factory. With complete control over the process, he developed a method of making belts that are so thin they’re almost translucent, as well as those of unheard-of tolerances (±0.6 micron thickness variation). For perspective, the diameter of a human hair is about 75 microns, and the track pitch of CD is 1.6 microns. I remember being floored the first time I compared the sound of a conventional belt with A.J.’s Revolution belt in the Basis 2800 turntable. Image stability was significantly better, the bass more solid, and the soundstage more precisely portrayed. How could thickness variations measured in tenths of a micron possibly affect the platter’s 20 pounds of rotating mass? According to A.J., variations in belt thickness along its length modulate platter speed because the centers of the two pulleys (for the motor and platter) are in the middle of the curved belt. Belt thickness variations momentarily change the ratio of the two pulley sizes, introducing speed variations. According to Conti, we hear such speed instability not overtly as pitch fluctuation, but as a reduction in instrumental realism, a less convincing soundstage, and de- gradation of low-level decay. (Incidentally, a company using DSP to remove speed variations printed on existing analog mastertapes, caused by mechanical imprecision in the original tape machine’s capstan, has reached similar conclusions about the sonic effects of speed instability.)

Although the Transcendence can accommodate any tonearm, I suspect that most users will choose the 9" Basis SuperArm 9 or 12.5" SuperArm 12.5. (See my review of the SuperArm 9 in Issue 264.) This ’arm is spectacularly great sounding, as I discovered when I replaced the Basis Vector IV on my Basis Inspiration turntable with a SuperArm 9 a few years ago. It is an all-out execution of the ideas developed for the Vector tonearm, including the unique bearing described in the sidebar (reprinted from my SuperArm review in Issue 264). The SuperArm uses the same bearing as the Vector: A.J. once told me that he thought there was no better bearing design or execution. 

The SuperArm is massive; everything about the ’arm is heavy-duty, from the armtube to the cup and pivot assembly to the headshell. In experimenting with specific modifications to a Vector tonearm, A.J. discovered sonic benefits in increasing stiffness and lowering resonances to levels below what had previously been considered acceptable. The armtube, made from a special alloy, features a “progressive damping” technique to reduce resonance.

One option is offered on the SuperArm—Basis’ patented VTA Micrometer, a device mounted next to the tonearm near the bearing that allows you to precisely return the ’arm to a specific vertical tracking angle (VTA). Note that the VTA Micrometer doesn’t change the VTA (you’ll need to loosen a set screw and move the ’arm by hand), but rather provides a precise and repeatable way to return the ’arm to a specific VTA. It works extremely well in practice. Finally, the integral tonearm wiring assembly, from the cartridge clips to the RCA plugs, was specifically developed for the SuperArm.

As you can imagine from this description, the Transcendence is expensive: $127,000 with the SuperArm 12.5. It is priced in the rarified strata of the world’s most ambitious turntables. When you look closely at the design and execution you can see where the money went. For example, machining large blocks of stainless steel with an intricate internal structure, like the suspension pods, must be very costly, as is the precision with which the parts are made. As expected from Basis Audio, the fit and finish is as good as it gets. A.J. once told me that when his metal parts were being anodized, he spent the day at the anodizing facility and stood behind the technician as the parts were removed from the chemical bath so that he could inspect them himself. Anyone who knew A.J. won’t be surprised by that piece of information.

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