C.E.C. SuperLink DA SL, Руководство пользователя

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SUPERLINK is a proprietary digital signal trans-
mission system that transports music signals and
synchronization(clock) signals with separate cables.
The SPDIF(Sony Philips Digital Interface) and AES/
EBU(Audio Engineering Society/European Broadcasting
Union) systems, commonly used in coaxial digital outputs
and optical outputs, transmit both the music and clock
signals through the same cable, and thus are prone to
jitter effects caused by the signals interfering with each
other.
SUPERLINK system transmits these signals separately
with multiple cables, requiring no encoding/decoding
process for data transmission. It minimizes deterioration
of the music signal during transmission by using the clock
signals from the D/A converter’s master clock generator to
achieve complete synchronization.
Each transmission path delivers/receives the following
signals.
MCK
(Master Clock): The CD transport receives the
master clock signal from the D/A converter through
this line, and functions as a slave to the DA converter,
enabling completely synchronized transportation of
audio data.
BCK
(Bit Clock): Sends bitclock signals, required for
digital data bit identification(e.g. sampling frequency)
or signal readout, from the CD transport to the D/A
converter.
LRCK
(L/R Clock): Sends left/right identi fi cation clock
signals from the CD transport to the D/A converter.
DATA
: Sends audio data from the CD transport to
the DA converter.
Remark:
Whenever changing the SUPERLINK input the master
clock line or source is also changed. This master clock
change will cause the CD transport to re-read the disc
information (TOC) resulting in cancelling every current
functional settings like programmed playback, repeat,
dimmer and so on. Set those functions again after re-
reading out TOC.
Transmission System
"SUPERLINK" Digital Signal
Press the FILTER button on the front panel or D.FILTER
button on the remote control unit to select a digital fi lter
type FLAT or PULSE.
Click noise may happen from speakers
or headphones when changing the digital
filter. It is recommended to change the
fi lter at low volume level.
Note
: When the display is " off " by dimmer setting
pressing once the FILTER button will return the
display brightness to the default " brighter " and
show the current digital filter type. Press the
button again to change the digital
fi lter type.
FLAT
digital Filter is very common in digital audio items.
The frequency response is almost perfect, but such fi lter
cause " ringing " in the time domain. Some energy of a
pulse signal is distributed in the time domain, before and
after the pulse centre. Any ringing before the signal does
not exist in nature.
PULSE
digital filter avoids the problems in the time
domain and thus has a very good response in the time
domain. The frequency response of the PULSE digital
fi lter shows a soft roll-off at high frequencies. This results
in about -2dB at 20kHz with an input sampling frequency
of 44.1kHz. For higher sampling frequencies the roll-off is
irrelevant and the " PULSE "
fi lter is the best choice. For
44.1kHz and 48kHz the better result may depend on the
whole system as well as personal preferences.
Differences in ringing of FLAT and PULSE
Wavy form of the digital signal passing through the circuit
FLAT PULSE
Digital Filter