Sonic Frontiers Transport 3 CD transport & Processor 3 D/A processor
In many ways, the Sonic Frontiers story defines the high-end entrepreneurial spirit. (See the SF interview with Robert Deutsch in Stereophile, Vol.19 No.6.) Remember, too, that the company's first foray into digital—the original SFD-2 processor some five years ago—was met with near universal acclaim and a Class A rating in Stereophile's "Recommended Components." SF maintained that Class A status with the SFD-2 Mk.II and the SFT-1 transport.
In spite of Sonic Frontiers' admirable track record, I was surprised at the ambitious scale of their new designs, most visible in the radical look of the Transport 3 and its iris-ported disc-loading mechanism, but even more impressively apparent under the skin of the Processor 3. However, after a careful examination of the Processor 3 prototype in SF's St. Francis Hotel suite at HI-FI '97, where it was on silent display, it was obvious that this was no mere souped-up SFD-2 Mk.II, but an all-new animal with several substantial engineering advances. Features that first caught my eye were its outboard power supply, discrete I/V conversion, and I2S-Enhanced interface designed by UltraAnalog, who had a major hand in the overall design of the Transport 3 (T-3) and Processor 3 (P-3). (I2S stands for Inter-IC-Sound.)
Could the Sonic Frontiers/UltraAnalog team have outdone themselves again, and not with just another Class A processor, but one that could redefine the Class A category? And what about the slick new T-3? Could its performance match its way-cool looks? More important, could a CD-only transport sporting a price tag a buck shy of $7000 find a place in the uncertain, rapidly changing world of digital audio?
These and other questions placed both products at the top of my HI-FI '97 wish list. But before we get to my answers, let's take a closer look at the make-up of both units.
Transport 3: an EYEris for the refined
I've seen transports that are more flashy or ornate than Sonic Frontiers' new show-stopper, but the Transport 3 is wonderfully slick, clean, and elegant—to my eye, one of the most attractive disc-spinners yet. The transport is quite large; viewed from the front, the width of the chassis—dominated by 5/8"-thick machined aluminum exterior plates sporting a shot-blasted, clear-anodized finish—is offset by its low-profile height of only 3¼". Add the special 1"-high Sorbothane isolation feet supplied by E.A.R., and the total unit height reaches just over 4".
The aluminum faceplate establishes the transport's clean look and is maintained throughout the design, with the exception of SF's trademark black front bezel, within which is centered an easy-to-read green LED display and a small power button. All other chassis-mounted controls are arrayed in a graceful arc on top of the device along the front right side of the disc-loading mechanism.
It's the disc-loader that gets the most oohs and aahs. Centered on the top plate of the transport is an aluminum ring 12" in diameter and 5/8" thick, with a hole slightly more than 6" in diameter cut in the center. When open, this hole exposes the transport's laser pickup, tracking sled, and disc spindle. Position a CD on the extended portion of the spindle, place the small magnetic cap on top of it to secure the disc while it rotates (this disc clamp meets the Philips standard for total mass to prevent excess motor stress), and press Close: Five vanes, each shaped much like the dorsal fin of a great white shark, rotate inward from their concealed positions beneath the outer ring to seal the opening tightly, with an action similar to that of the iris shutter on an SLR camera. This proprietary mechanism is driven by a precision Swiss motor and is definitely cool to watch as it makes a distinct whirring sound not unlike the meat slicer at a local deli (though considerably quieter). With a CD spinning underneath, opening and closing the iris hatch really does look like an eye from an M.C. Escher painting winking at you—or, depending on your frame of mind, an exit door on one of the motherships in Mars Attacks!
The rear panel offers a full set of digital outputs, including an AES/EBU, S/PDIFs of both the RCA and BNC varieties, ST-Type glass optical, the all-important I2S-Enhanced 13W3 output connector, and an infrared port for linking the transport to an outboard IR repeater. Of course, there's a standard IEC power inlet as well.
Though only three hex-head screws connect the aluminum side plates to the thick top lid, if you feel the need to gaze at the T-3's innards, be careful. Lift the lid slowly and only slightly—the transport mechanism itself is mounted to the bottom center of the heavy lid, with control, signal, and power wiring connecting it to the main board and power supply.
What you'll see will be three circuit boards and the various connectors mounted inside a 14-gauge black-plated sheet-metal subchassis, to which the side and front machined aluminum outer plates are attached. The largest board is a long L-shaped, dual-sided, solder-masked pcb that runs along the left side and rear section of the lower subchassis. This board contains the circuitry for all the output options. The 12 regulated low-impedance, ultra-low-noise power supplies spread across this board are fed by a large custom-built toroidal transformer in the upper right corner of the subchassis. The total capacitance of these supplies is around 25,000µF, close to that of some small amplifiers!
Also on the T-3's main board is a "proprietary" AT cut-crystal master oscillator to provide precise timing for transport functions, as well as for the word clock feeding the outboard digital processor. According to Chris Johnson, great care was applied in the execution and layout of these dual-cascaded, RC-filtered voltage regulators, to provide DC power with the lowest noise possible for critical clocking functions, and to ensure the greatest immunity from phase-noise contamination of the jitter spectrum. I suspect that this feature and the I2S-E interface are two of the biggest contributors to the unit's rock-solid performance. The transport mechanism is a relatively new version of Philips' Professional CDM-12, and was specifically designed for top-loading players. It incorporates a rigid die-cast construction, a three-beam optical system, and a unique servo processor claimed to enhance the T-3's disc-tracking ability.