ALLNIC AUDIO D-5000 DHT, Руководство пользователя

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WAVERSA SYSTEMS CUSTOM DIGITAL PROCESSING
With a digital section designed by Dr. C. Shin, principal of WAVERSA SYSTEMS and an expert in high-
resolution digital and digital to analog design for both military and commercial applications, the D-
5000 DHT DAC is unique in the marketplace. Except for the DAC chip it employs, the ES9018K2M
SABRE 32 Reference DAC (“Sabre DAC”), none of the D-5000 DHT DAC’s digital components are
sourced from the audio supply market. In addition, the USB interface and SPDIF receiver are
specifically customized for use in the D-5000 DHT, and custom built high end up-samplers are
utilized for user selectable DSD conversion and PCM up-sampling.
The D-5000 DHT offers the listener the flexibility to select listening directly to:
•
the source drive’s audio signal at its native sampling rate, or down-sampled if that signal
is above the limits of the D-5000 DHT’s digital inputs, 192 KHz (so long as the source is of
sufficiently high quality – see “Operation”);
•
a PCM signal from the source drive converted to DSD 128 in “real time”; or
•
a PCM signal up-sampled from the source drive’s native rate by a custom up-sampling
chip.
The ES9018K2M SABRE 32 Reference DAC is a high performance 32-bit, 2-channel audio D/A
converter with sampling to 32/384 KHz, DSD 128 and a 1.5 MHz up-sampler using a field-
programmable gate array (“FPGA”) USB interface. In the D-5000 DHT, however, the Sabre DAC chip
is used for digital to analog conversion only; all audio signal processing is performed by a Waversa
Systems custom designed processing chip set.
The D-5000 DHT converts PCM to DSD in real-time when CONV (“Conversion”) is selected using the
D-5000 DHT’s chassis face or remote controls. When conversion to DSD is selected, all PCM input
samples are converted to 128 DSD via a custom built internal 5.6 MHz up-sampler and FPGA DSD
converter.
The D-5000 DHT up-samples PCM when UPSAMPLE is selected using the D-5000 DHT’s chassis face
or remote controls. When up-sampling is selected, all PCM input samples are up-sampled using the
Waversa Systems custom built 1.5 MHz audio signal processing chip, which also then down-samples
to the selected sampling rate prior to sending to the Sabre DAC for digital to analog conversion.
The USB interface is implemented through network player hardware by Waversa Systems and is
UAC2 standard compliant. This provides an extremely clean digital audio signal through complete
galvanic isolation, which strips the digital signal of any PC noise commonly created by a server’s
internal power supply. Firmware updates and music data are also communicated through the single
provided USB input. This is accomplished by a special interface, again unique to Waversa Systems.
Data under-run or over-run and, therefore, distortion can occur when a source’s word clock and a
DAC’s internal word clock are not synchronized absolutely. When an external clock is used, potential
errors caused by data under-run or over-run inside a DAC can be eliminated. The D-5000 DHT
provides connections for an external word clock. In addition, it is planned to update the D-5000
DHT’s current high-end internal word clock implementation to an even more highly advanced mode