Although for our purposes Air Force 1 refers to the Japanese company TechDas’ new state-of-the-art turntable, the company freely admits it helped itself to the moniker of the presidential jet because the design is intended to be the “first among the first.” In other words, this is an all-out, no-holds-barred assault meant to answer and exceed every aspect and parameter of turntable performance. And it’s priced accordingly: $105,000 for the ’table alone, far from the priciest but still up there. Even these days, with ever-escalating cost and complexity (not to mention extravagance and extremity) in design, the AF1 is a component of rare sophistication, ingenuity, thoroughness, and the very highest competence and execution. The auteur is Hideaki Nishikawa, a man with more than five decades of distinguished work in high-end audio, starting in the mid-sixties at Stax, where he helped develop those fabled electrostatic headphones. Several years later he designed turntables and tonearms for various manufacturers, including Infinity’s famous Black Widow, much admired by TAS reviewers and readers in the early Eighties. (I owned one myself for a while, and it rivaled the SME 3009 series with high-compliance, low-mass, moving-magnet pickups like top-of-the-line Shures and ADCs.) From there he wound up at Micro-Seiki, where he designed what he considered a statement product: the SX-8000II turntable, an air-bearing ’table with vacuum hold-down. Drawing upon the best ideas in the 8000II and allying them to the latest research in materials and technology, the AF1 is his second statement turntable. Asked why such a long time passed between the two, he replied, “I waited for the technology to improve.” Stella, TechDas’ international distributor, has not been exactly reticent in trumpeting the AF1 as “the best turntable in the world.”
This is so complex a turntable that to describe its rationale, features, and setup fully would far exceed the space limitations of even a very long review. Inasmuch as I imagine any buyer will have a trained dealer do the setup, I’m going to concentrate on those design aspects that seem to me to account for its extraordinary performance, most of which involve air force and pressure, hence the name. Air bearing for the platter, air suction for the vacuum hold-down, and air bladders for the suspension system triangulate the nucleus of the AF1 design. In and of themselves, none of these is new, but I don’t know of another ’table that has combined them into one component. The most controversial of these continues to be the use of vacuum to secure the record to the platter surface. The typical objections are two: damage to vinyl owing to high vacuum pressure, and the so-called ripple effect of most vacuum pumps—that is, the pulsating of the pump to maintain the vacuum. The answer to the first is that, yes, high vacuum-pressure does damage, so the solution is to avoid it by using low pressure, which is benign. So far as I am aware, all current vacuum systems follow the practice pioneered by David Fletcher’s SOTA Cosmos, introduced in the early Eighties, which employs an initial high suction to evacuate the air and establish a seal, after which the pressure drops to a very low, harmless level more than adequate to maintain the seal and hold the record securely to the platter. The amount of time high suction requires to make the seal is design dependent, but even the longest—around 30 seconds in one brand, if I’m not mistaken—is not remotely long enough to do any damage. Even with the most warped records, the AF1 never needed more than five seconds to establish a seal. In my own experience of more than two decades with several SOTAs, I’ve never experienced any degradation of my records that could be attributed to vacuum hold-down.
As for the ripple effect, I imagine there must be something to it on the strictly theoretical level, since Nishikawa makes a point of addressing it in the AF1 with a sophisticated form of filtering—involving glass-reservoir chambers—that smooths out the ripples and thus prevents any modulation of the pumping from affecting the audio signal at the stylus-record interface. I have to say that I’ve never actually been aware of any deleterious sonic effects that I could attribute to rippling, chuffing, or any other untoward modulatory byproduct of pumps in any vacuum hold-down turntable I’ve ever heard, including products by Basis, Continuum, and SOTA. Suffice it to say that for me there is no more effective way to marry an LP to the platter and thus to damp vinyl resonances and drain away spurious noises from the stylus-record interface than a well-engineered vacuum hold-down. I can’t say that the AF1’s is better than all others out there, but it’s better than any other I know about; it’s also hard for me to imagine it could get any easier, more foolproof, or more trouble-free. The pump is dead quiet: Even standing right next to the open shelf on which the pump was placed, I couldn’t hear it in operation. And it’s baby-simple to use: Put on a record, hit the “Suction” button, and in moments—about a second for most records—the LP is flattened to the platter, the pressure drops to maintenance level, and you’re off and running. The rewards in background quietness (more on this anon), dynamic range, and tracking—all owing to the elimination of warps—must be heard to be believed.
The main platter employs an air bearing, for which Nishikawa uses the same kind of filtering to ensure that the platter itself rides on a rock-steady cushion of air, free from ripples and modulations of the air pump (a separate pump from the vacuum). Air is also used for the suspension. The base rests on three feet, adjustable for level via large knobs on the plinth, each foot containing a bladder and a reservoir designed to provide a damping to resist footfalls and structural vibration. A bicycle-type pump (supplied) is used to fill the bladders while a built-in bubble-level and spacer see to it that proper pressure goes to each of the three bladders. Inasmuch as an air bladder is basically a balloon or inner tube, it will inevitably leak over time, each bladder more than likely leaking at a different rate, just as tires do. This is no cause for concern. For one thing, the leakage is exceedingly slow and will probably go unnoticed for several months. There is no need to obsess about this. According to Robert (“Bob”) Graham, whose Graham Engineering Corporation imports the AF1, “The air suspension has a rather low Q and will not be adversely affected by minor variations. All that’s really needed is an eyeball approximation using the bubble level once every month or two—less effort than, say, cleaning the record every time or dusting off the stylus tip.” In the several months I had the turntable for review, I never noticed the bubble level change once.
One of the most novel and sophisticated aspects of the AF1 is how it addresses issues of speed accuracy and speed constancy, which are not the same things. Many turntables, notably direct-drives, employ fast-acting servos to ensure speed accuracy. But the problem with this is that it can result in a kind of constant “hunting” for the correct speed, which in turn can have a deleterious effect on the sound because, the argument goes, the speed is never strictly speaking constant. Some designers even believe it’s preferable to sacrifice that last degree or two of speed accuracy in favor of speed constancy in the interest of greater playback stability and solidity. Nishikawa has gone to great lengths to ensure both. The two phases of the asynchronous motor are each driven by a 50-watt Class A amplifier. Once the speed is selected—33.33 and 45 rpm are available—a “torque switching circuit” is engaged to bring the very heavy platter up to speed, which takes a few to several seconds. When the platter reaches speed, the circuit reduces torque to the minimum necessary to maintain speed and the servo is completely disengaged and out of the system. Speed thereafter is controlled only by the motor and the inertia of the exceptionally heavy platter. If due to some external force, such as brushing the record or stopping the platter by hand, the sensor automatically reengages to return rotation to correct speed.
A nice feature is the vacuum can be engaged or defeated independently of whether the platter is moving. Another nice feature is a tachometer with digital display that allows pitch to be altered in +/- 0.1 percent steps over a 10 percent range. Pushing either of the speed buttons returns to 33 or 45. Two parts that are essential for this turntable’s speed accuracy and constancy are the belt (4-mm wide, made of polyurethane flat fiber) and belt tension, which are also critical to the AF1’s overall performance. Like many belt-drive turntables these days, the motor is outboard and detached from the main chassis, which means that getting the correct belt tension involves a certain amount of cut and try. But the AF1 has a built-in tension-calibration circuit that automates the process. Your dealer will do this as part of the setup, but in case you ever move the turntable or have to get a new belt, you can recalibrate the tension on your own. (The exceptionally comprehensive manual provides full instructions.) During the review period, there was absolutely no speed drift. Indeed, as with every other aspect of this complex design, the tension-calibration system performed flawlessly. Day by day I’ve rarely experienced a record-playing setup that was easier or more pleasurable to use than this one: once set up, it just works.
Unique to my experience of turntables, the AF1 offers a choice of three platters. The base layer for all three is non-magnetic stainless steel, while the upper platter options vary from aircraft-grade, extra-super duralumin (the most neutral, supplied with the review sample), non-magnetic hard-processed stainless steel (for punchier bass), and an acrylic-resin black methacrylate (for a softer, presumably more tube-like sound). The platters are available with or without vacuum (though I have no idea why someone would eschew vacuum, especially when it’s this well implemented), and of course all three can be purchased for those who desire the ultimate in flexibility or want to cater to audiophile neurosis: I remember one audio reviewer of some celebrity from the glory days of the Seventies and Eighties, who used to rotate the platter mat for optimal playback of each individual record and note the position in order to return to it for the next playing. The AF1 comes with one mounting board drilled for the ’arm of choice, but it will support an additional board; standard and 12-inch ’arms can be accommodated.
The (by-now) predictable sandwich construction for the base uses three layers of considerable mass for resonance control, suppression, and damping: pure aluminum for the base; duralumin for the middle; another aluminum with an anodized surface for the top chassis, which gets a sapphire-hard finish that resists scratches. I do have to say that unlike so many Space Age-looking turntables, this one, with its light silver-grey matte finish, is much less bothered by scratches and shows dust much less plainly than any others I’ve used this side of wooden bases. As is clearly evident from the photographs, the turntable is physically large and heavy. Although it is not a piece of furniture or any sort of structure that takes up floor space in your listening room, the AF1 tilts the scales at a whopping 221.5–238 pounds, depending on the platter option. This mandates a very sturdy equipment shelf with a width of 30 inches and depth of 20 (though with cabling 24 would be better).