Alpha DAC Reference Series
Official Site
We could, like many other manufacturers, convert 1-bit DSD to multi-bit within the Alpha DAC Reference Series and show "DSD"
in the front panel display. That would be the easiest approach from a marketing standpoint and would also be very simple and low in cost to implement.
But that approach would also mean increasing the amount of processing in the DAC during playback which would degrade audio quality,
and audio quality is the reason the Alpha DAC Reference Series exists.
Fortunately, virtually all reproduction of DSD files using external DAC’s is with a computer based music server as the source.
If 1-bit DSD to multi-bit conversion is done first in the computer it can be performed with extremely high precision and superior filtering that preserves
all of the content of the DSD file. Computer DSD to multi-bit conversion can be at least as good as that performed in a DAC and without adding
processing noise near or in the D/A converter chip. Also, conversion of DSD to 176.4 kHz, 24 bit AIFF or WAV files can be done ahead of time resulting
in no conversion processing occurring during playback. Another advantage of computer based DSD to PCM conversion is that if higher performance DSD versions
such as DSD 4X appear in the future, they can be easily supported with a software upgrade.
For all of these reasons, DSD capability for the Alpha DAC Reference Series is provided by a state of the art software application, JRiver Media Center,
that provides either real time conversion of DSD 1x and DSD 2x to 176.4 kHz, 24 bit PCM during playback or, for the best possible audio fidelity,
easy conversion to 176.4 kHz, 24 bit AIFF or WAV files prior to playback. The JRiver Media Center software application is included in the price of the
Alpha DAC Reference Series and either Windows OS or Mac OS versions are available.
Specifications
Input sampling rate: 32kHz to 192kHz
Input word length: 24-bit
Ultra low phase noise Precision Clocking at 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz and 192kHz sampling rates ± 100 ppm
Two channel analog stereo outputs: XLR balanced with pin 2 positive and RCA unbalanced
Digital Inputs: AES - XLR, 110Ω; SPDIF1 - BNC, 75Ω; SPDIF2 - BNC, 75Ω; TOSLINK - Toslink optical connector
HDCD decoding detects 16-bit flag at 44.1kHz or 24-bit flag at all sampling rates
Multiple digital filter options
Balanced analog output level: +18dBu (6.15Vrms) maximum, +12dBu (3.1Vrms) or lower recommended
Unbalanced analog output level: 3.25Vrms maximum, 2Vrms or lower recommended
Digital volume & balance control: 0.1dB/step with .05dB/step L/R gain trim, 60dB range
Frequency response at β 88.2kHz sampling rates: ± 0.1dB from < 0.1Hz to 35 kHz, - 3dB at 59kHz for 176.4kHz and 192kHz sampling rates
Distortion at recommended levels: all products β -120dBFS
THD+N at maximum level: < -110dBFS
Firmware upgradeable through signal inputs
Enclosure dimensions: 3.5βH X 17.5βW x 12.5βD
Weight: 30 lbs.
Mains power: 100/120/240VAC, 50/60Hz
Power consumption: 25W
Reviews
The Absolute Sound /
Mono & Stereo
