Wadia 27ix & Wadia 270 transport Jonathan Scull Follow-up 2002

Jonathan Scull wrote a Follow-up in January 2002 (Vol.25 No.1):

I was stunned when I unpacked the Wadia 270 CD transport. For $7950, it's a beautifully built component—more than 30 lbs of machined aluminum, down to the brackets, clamps, and chassis components. Even the two damping plates sandwiching the clock and output circuit boards are each machined from a solid block of aluminum. The 270 is big and heavy, with a solid disc drawer and an easy-to-read display, and comes with wide, easily adjustable spiked feet and elegant gray spacers for docking with the $8950 27ix Digital Decoding Computer, if you've a mind to do so. (I set them up separately on air stands.)

John Atkinson had reviewed the 270/27ix combo in the April 1999 Stereophile—and in late 2000, Wadia became a division of Audio Video Research Incorporated. Wadia products are now made at AVR's new facility at 795 Highland Drive, Ann Arbor, MI 48108 (Tel: (734) 975-4217. Fax: (734) 975-4299.). AVR calls itself "a new company committed to continuing Wadia's tradition of sonic and technological excellence," but given the change in ownership and manufacturing, a Followup seemed appropriate.

The transport itself is based on a Teac CMK 3.2 Full Disc-Clamping Mechanism upgraded with Wadia's own damping materials. Around back you'll find an ST glass optical output, an S/PDIF on a BNC connector, then an AES/EBU connector, and finally Wadia's ClockLink output, also with ST glass connector. These are glass guys. Off-the-shelf integrated glass optical transmitters combine the driver circuitry and laser transmitter into one unit. But according to Wadia, such transmitters are intended for use in long-distance telecommunications; when used in short audio lengths, they overload the receiver and cause jitter. So Wadia designed a discrete glass optical transmitter tuned for shorter lengths which, they claim, lowers jitter. They say the improvement can be heard in any D/A converter with a glass-fiber input.

The 270's Resolution Enhancement feature adds "carefully constructed" uncorrelated signals—9 bits' worth of Triangular Probability Distribution Function (TPDF) dither—below the CD's least significant bit. And there ya go: 24 bits, straight out of the transport. You can also choose no processing for a plain, unprocessed 16-bit datastream—which you might or might not want to activate, depending on the DAC you're going into. Click on Wadia's Technical Papers for more information.

The 270 hosts a host of tasty features, including the all-important ClockLink function to hook up with one of their 'Linked Digital Decoding Computers—like the 27ix DAC. ClockLink positions the master oscillator right next to the DAC chips rather than in the transport, with a claimed result of lower jitter.

The 27ix Digital Decoding Computer ($8950), too, is one high-tech piece of machined aluminum. In fact, it's got so much technology on tap that, again, you should look up JA's original review, or visit the Wadia website.

When the 27ix starts up, it gives the user the software version it's running, the current being v3.0. The latest version of Wadia's DigiMaster time-domain interpolation filter is optimized to preserve time and phase information and operates with 24-bit precision. The algorithms are part of a processing system that upsamples digital info to 2.8224MHz (SACD territory) "while differing in time- and frequency-domain characteristics." Wadia points out that the DSP allows them to custom-match the performance of the digital and analog portions of the circuit "to a level not achievable with IC-based solutions."

When I reviewed the Boulder 1012 D/A preamplifier in December, I learned that the Burr-Brown 1704K D/A chip's maximum speed is 768.0kHz, and Wadia can't change that. How they achieve the screamingly fast upsampling rate of 2.8224MHz from these B-B DACs is by sending separate "time-staggered" packets of 705.6Hz data to each of four converters per channel.

Wadia points out that using multiple DACs randomizes the errors that might become an audible pattern in a one-DAC-per-channel system, and time-staggering the data permits them to reach a sample rate almost 30 times the data rate of 96kHz upsampling systems. This is pretty remarkable. Parallel processing: It's what that wedding guest in The Graduate would have said to Benjamin today, instead of "Plastics."

Regarding the smoking gun held to the foreheads of digital designers today by the competing hi-rez media, the Wadia 27ix is a flexible design sporting software-upgradeable circuitry, and a rear-panel insert to allow for new input or output hardware, should the need arise. The i upgrade for the 27 adds ClockLink, costs $1300, and is indispensable to getting the best sound, I found. The x upgrade ($995) gives a 27i v3.0 software, and adds 96kHz input capability and the selectable algorithm feature. Also not chopped liver. A v3.0 upgrade for 27ix owners runs $695; basically, it adds the selectable filter algorithm feature. And yes, you need to have the i upgrade performed before the x upgrade to v3.0 software.

So just how excellent did the 270/27ix sound?

In a word, fab. And at a combined price of $16,980, they'd better. The Wadia combo sounded pretty close to the Linn Sondek CD12. Damn, it was good, especially—well, only through the glass connector with the ClockLink engaged. Without it, forget it—everything just collapsed and got strident. Unless a recording was particularly hard, I liked the "A" dither mode on the transport, then the AES/EBU (giving up the ClockLink), followed not too distantly by the BNC connection. (When you turn ClockLink off, you do benefit from Wadia's classic RockLock, a "cascaded phase-locked loop system.")

Listening to many of the recordings I used in the Boulder review, I found that the 270/27ix's bass was extraordinary, the transitions upward smooth, the midbass to midrange easy, the midrange itself quite tasty and textural. For the most part the highs were sweet and engaging, offset by only the tiniest hint of digititis on top, that slightly hard sense much ameliorated by the whisker of rolloff effected by the Wadia DSP right at the top of the audible frequency range. For example, I've often complained that Duke Ellington's piano on This One's for Blanton (Analogue Productions CAPJ 015) sounds a bit metallic through some components, but I had no problems enjoying the tunes with the Wadia calling the shots. It sounded open, fast, and colorful, very palpable and textural, with lots of pace.

When I fed the 27ix a 24-bit/96kHz Chesky SACD or Classic DAD, the mids were smooth, textured, sexy, and delightful, the extension excellent. There was bags of air, with no hint of grain or other audio gremlins.

All the above comments were made using the processor to feed my usual preamplifiers. But as the 27ix incorporates a digital-domain volume control, it can be connected directly to a power amplifier. For a reviewer, a preamp is really important—but if you don't spend your life fooling with cables, going direct can be staggering in its clarity.

I ran the 270/27ix direct into three different sets of monoblocks—Linn Klimax Solo 500s, Krell FPB 350Mcs, and BAT VK-150SEs—and the sound was terrific, bold, and dynamic, and always colorful and romantic. Go below around "70" or so on the Wadia's volume control and you begin to drop important bits, however.

You could go for the 27ix DAC alone and live happily ever after. But provided your family won't go hungry, the extremely high performance of the ClockLinked 270 with 27ix makes this combo one fine integrated digital front end for 16-bit/44.1kHz "Red Book" CDs.—Jonathan Scull