Here we have a lovely, young example of Berkeley Audio Design's Alpha USB, tenderly cared for in my smoke-free, pet-free home since I bought it 2 years ago from an authorized Berkeley retailer. For those of us with CD players or servers or computers that have USB outputs, the Alpha USB is for sure the route to the very best sound quality. Berkeley has been the industry leader in outboard conversion from USB to SP/DIF for more than a decade.Here's how it works, in Berkeley's own words: The Alpha USB is an asynchronous High Speed USB to digital audio interface that extracts the highest possible audio quality from computer audio sources. The Alpha USB features a High Speed USB 2.0 input data connection and switch selected audio output signal type – either coaxial SPDIF using a BNC connector or balanced AES using an XLR connector. Sampling rates up to 192 kHz and word lengths up to 24 bit are supported. Great care was taken in the design of the Alpha USB to isolate the noisy computer/USB environment from the digital audio output. The USB receiver and processing are powered by the computer, while the output master clocks and line drivers are powered by a separate isolated linear power supply. Two key factors combine to achieve the excellent audio performance of the Alpha USB - the unprecedented degree of electrical isolation between the USB input connection and the audio output and the very low noise/low jitter performance of the individually tested audio output master clocks. The Alpha USB is designed to work with both Apple Macintosh and Windows PC computers. Apple Macintosh computers using Snow Leopard or later operating systems have a High Speed USB Audio Driver that interfaces directly with the Alpha USB. It is not necessary to install a special driver. Microsoft Windows PC’s require the included Alpha USB Windows driver which works with Windows XP, Vista and 7. Here's what the reviewer said in TAS: "The Berkeley Audio Design Alpha USB is a breakthrough product that not only overcomes the limitations of the USB interface, but provides a state-of-the-art method of getting audio out of a computer. Moreover, the Alpha USB makes this reference-quality performance available to non-technical music lovers who have a Macintosh and a DAC. ... One day computer-based music systems will be simple to set up, foolproof, ubiquitous, and uncompromised in sound quality. The Berkeley Alpha USB represents a giant leap forward in realizing this goal." As you can see from the specs below, the Alpha USB's output will accept either an AES (XLR) digital cable or a coax BNC digital cable to connect to the input on your D/AC. SPECS: Type: USB-to-S/PDIF converter
Input: High-speed USB 2.0, Type B jack
Output: Switch selectable— coaxial SPDIF on BNC, balanced AES on XLR
Supported sampling rates: 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz, 192kHz
Supported word lengths: Up to 24 bit
Supported operating systems: Apple Macintosh and Microsoft Windows
Mains power: 100 or 120 or 240VAC, 50/60Hz, IEC power input connector
Power consumption: 3 Watts line, 1.5 Watts USB, designed for continuous operation
Dimensions: 10.5” x 2.5” x 5” (including feet)
Weight: 2.5 lbs. My asking price is very fair and firm, so please, no low-ballers, tire-kickers, or time-wasters. Shipping anywhere in the good ol' U.S. of A is included at the asking price. PayPal is welcome and adds the usual small fee. Any questions, just ask. Many thanks for looking!
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