Apogee Introduces DA-2000 Reference Stereo D/A with UV22, Multiple Inputs
July 10, 1998
The new Apogee DA-2000 is a fully-featured 20-bit D/A converter/switcher in a standard 2U rackmount configuration. In addition to precision D/A conversion, the unit features six digital inputs - four AES/EBU inputs on gold-plated XLR connectors and two S/PDIF inputs on gold-plated RCAs - with direct front-panel selection, allowing the DA-2000 to form the hub of a digital audio monitoring system. Indicators above each input selection button show the presence of signal, and a legend indicates the input number, illuminating when selected. Three input sampling rates are provided: 32, 44.1 and 48 kHz. The sample rate is detected automatically. An illuminated legend indicates the currently selected sample rate.
The DA-2000 is a 20-bit resolution converter, with quantization noise levels significantly below the noise floor. In addition the unit includes the highest quality anti-imaging filters to remove unwanted frequencies above half the Nyquist limit. These filters employ a proprietary curve providing a gentle rolloff to minimize the phase errors at high frequencies normally introduced by the filtering process. The rolloff can be made especially gentle thanks to the oversampling nature of the converters, which significantly raises the Nyquist threshold, allowing a more gentle filter slope to be employed. A resolution indicator is provided which automatically displays "16" for 16-bit signals and "high" for signals with higher precision.
The DA-2000 includes Apogee Electronics Corporation's exclusive UV-22® Super CD Encoding system, which flawlessly translates a high-resolution digital signal into the 16-bit domain without audible loss of detail. Unlike noise shaping or other techniques, UV-22 does not increase the noise level above the theoretical 16-bit minimum, placing it 4-5 dB below that of "flat dither". Unlike dither and noise shaping, UV-22 is algorithmically, rather than randomly generated, placing a "clump" of energy above the audible range, which flawlessly encodes the detail in the high-resolution signal. The UV-22 control on the DA-2000 encodes the digital signal before it passes through the converter. Although primarily designed for treating high-resolution sources, many listeners report that an improvement may be experienced when encoding 16-bit input signals.
The DA-2000 features a high precision 1 kHz tone generator with user-presettable level (adjustable on the rear panel between 0 and -20dB). To minimize distortion of the test oscillator signal, the tone is generated digitally and is applied to the entire converter, confirming correct level alignment of both analog and digital circuitry.
Fundamental to the design of the DA-2000 is recognition of the fact that both analog and digital excellence are required to create a digital audio converter capable of delivering the highest performance, lack of coloration and faithfulness to the highest quality digital input signals. True balanced outputs are provided on professional audio standard gold-plated XLR connectors. In addition, gold-plated RCA connectors provide left and right high quality unbalanced analog outputs.
In keeping with the high quality design principles inherent in all aspects of the DA-2000, the unit features a fully linear power supply with low-radiation true toroidal transformer for the lowest possible supply noise. The DA-2000 will be shipping in August.
For more information, visit their web site at www.apogee.com.
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