When I reviewed the Bryston BDA-2 DAC in Issue 233, I ultimately concluded that, as good as its USB input sounded with the USB cables that I had on hand, ranging from the entry-level Belkin Gold through the top-of-the-line WireWorld Platinum Starlight, it still sounded considerably better when connected to the BDP-1 Digital Player through my ED-120 SPDIF cable.
In the intervening years, I have continued searching for a USB cable that would allow the BDA-2’s USB input to equal the performance of its SPDIF and AES/EBU interfaces. I even built a prototype non-standard “data only” USB cable that entirely eliminated the noise-prone 5-volt power line and ground wire, thereby removing those known sources of interference. This prototype USB cable sounded dramatically better than even the most expensive commercially available alternatives I had tested, but it still didn’t sound as good as SPDIF.
On a wild hunch, I ordered an inexpensive but distinctively designed USB 2.0 cable from a mainstream computer accessory manufacturer, hoping that it might work as well as a USB audio cable. From the moment that this cable was installed, even “dead cold,” it utterly trounced every previous USB cable that I had auditioned, including my experimental prototype. After an extended warm-up period, I conducted a lengthy run of skeptical critical listening comparisons, and enthusiastically concluded that this USB cable finally enabled the BDA-2’s USB input to perform at a level competitive with the best SPDIF and AES/EBU alternatives.
Eager to share this encouraging development with industry associates and fellow listeners, I hit the web to stock up on this USB cable, only to find that it had been discontinued by the manufacturer! I scoured the ’Net, and managed to locate half a dozen samples, but further searching has been futile. Disappointed, I moved on, testing a few more designs from well-known high-end manufacturers, none of which approached the performance of my unlikely new “accidental reference” USB cable.
Continuing my quest, I recently found another USB cable that may ultimately prove even better than the aforementioned accidental reference. Fortunately, the Japanese-designed Oyaide Neo d+ Class A USB 2.0 cable is currently available from multiple sources at eminently reasonable prices: $50 for 1 meter, $70 for 2 meter, and $90 for 3 meter lengths. Curiously, the Oyaide d+ series USB cables are not generally available through Oyaide’s high-end accessory distributors; rather, they appear targeted to the professional/performing-musician market.
The Oyaide d+ USB cables feature a flat geometry, similar to that of products from other manufacturers. The black-jacketed Class A model incorporates gold-plated connectors and high-purity copper conductors, though the specific copper formulation has been changed recently, and different suppliers still carry overlapping stock, depending on length. I have one of each, and thus far cannot differentiate between the two by listening.
The less expensive Class B model sports a garish neon-green jacket, and silver-plated copper conductors. The more expensive Class S model is fitted with a white jacket over substantially thicker copper conductors of the same formulation used in the Class A cable, but terminated with platinum- and rhodium-plated connectors. Perhaps the greater conductor area of the Class S cable might benefit longer runs, but the Class A cable seems well-suited for the typical 1 or 2 meter connections between USB sources and DACs, without excessive mass or stiffness stressing the components’ jacks. Prior experience with silver-plated copper and pure silver USB cables informed my decision to opt for the Class A cable’s high-grade copper conductors. For further information visit neo-w.com, but be forewarned that the text on the English site is in dire need of a new translation.
With some trepidation, I installed a 1-meter Oyaide d+ Class A USB cable between the Bryston BDP-1 Digital Player and Bryston BDA-2 DAC. Initial impressions were promising, but not as immediately compelling as my first exposure to the accidental reference USB cable. However, it has become increasingly apparent that for some inexplicable reason, most USB audio cables (and/or the circuits they connect) take an inordinately long time to warm up. Since the beginning of the digital audio era in the 80s, I’ve learned to allow at least four days for CD players, DACs, and other digital components to stabilize after first being powered on. The necessary warm-up period for USB circuits seems to be at least a couple of days longer, perhaps substantially longer.