User manual

20
Operation
The example above shows the MC-3+USB set to the externally referenced re-clocking mode. A DSD256 signal is being received
via USB (refer to »REFERENCE« & »CLOCK IN«). The audio outputs are set to an output clock rate of 176.4 kHz (refer to
»CLOCK OUT«) and will output the converted PCM signal of the DSD stream. Both lock indicators in the »STATUS« section are
illuminated – the top LED indicates the lock to the DSD signal, while the bottom LED confirms synchronization to the external
clock reference.
»INTERN« & »RE-CLK«
The »INTERN« and »RE-CLK« LEDs will light up when »RE-CLK« mode is selected; indicating that the re-clocking mode based
on the internal clock oscillator is now active. As a factory default, »USB-PCM« will be selected as the first available audio
reference in the »REFERENCE« menu (both the »WCLK« and »1-10.0M« LEDs are illuminated). Press the menu key once and
you’re entering the »REFERENCE« menu. Toggle the »SELECT« key to choose one of the five available audio references. These
will now be re-clocked with the internal ultra-low jitter clock signal, format-converted, and passed on to all audio outputs with
the same clock rate simultaneously.
Attention
Special use case: USB-DSD/DoP as audio reference
When selecting »USB-DSD/DoP« as the audio reference in »RE-CLK« mode, the MC-3+USB will convert a DSD or DoP signal to
a PCM audio signal in real time. The converted PCM signal will then by processed re-clocking algorithm and will be available at
the different audio outputs. The original DSD and DoP streams will not be passed transferred to the outputs.
Furthermore, a clock rate has to be selected for the PCM audio outputs in the »CLOCK
OUT« menu. Switch to the »CLOCK OUT«
menu by pressing the »MENU« key where you can choose between 44.1, 88.2, and 176.4 kHz. The same applies when the MC-
3+USB is operating in the externally referenced re-clocking mode.
»EXTERN« & »RE-CLK«
This is a very unique feature that only available in you MC-3+ Smart Clock USB! After selecting the first re-clocking mode, press
the »SELECT« key once again and the »EXTERN« and »RE-CLK« will light up to indicate that re-clocking based on an externally
applied clock reference is now active. Per default setting, »USB-PCM« (both »WCLK« and »1-10.0M« are illuminated) will be
selected as the fist available audio reference. Press the »MENU« key once to access the »REFERENCE« menu and toggle the
»SELECT« key to choose one of the five available audio references.
Please note: the system will however expect an external re-clocking reference at the »WCLK & 1-10M IN« BNC input on the
rear panel in this mode. If this reference is not provided, the re-clocking process will not be active. Possible re-clocking referen-
ces are:
Word Clock 32.0 kHz – 192.0 kHz
1.0, 2.5, 5.0, 10.0 MHz
If both a valid audio and a re-clocking reference have been applied, the blue lock LEDs »MAIN REF« and »RE-CLK REF« in the
»STATUS« section will light up and the re-clocking process will be started. The clock rate of the incoming digital audio signal
will be displayed in the »CLOCK
IN« section of the front panel. The Word Clock output signals can be multiplied using the
»CLOCK MULTIPLIERS« menu as described in the »Selecting Clock Multipliers« section.
Selecting one of these externally referenced re-clocking options enables re-clocking a digital audio signal with an external
clock reference of a peripheral master clock generator. In all cases, the converted digital audio and Word Clock signals will
have the same clock rate as the digital audio source. However, there is no phase lock between input and output signals in this
mode!
CLOCK MULTIPLIERS
1 2 3 4
MODE
32.0
48.0
INTERN
RE
-
CLK
EXTERN
×
1
×
8
×
4
×
244.1
88.2
96.0
×
256 SC
×
512
×
256
WC176.4
192.0
REFERENCE CLOCK OUT
WCLK
1
–
10.0M
USB
-
PCM
AES3/11
S/P
-
DIF BNC
AES3/11id
S/P
-
DIF OP
USB
-
DSD/DoP
STATUS
LOCK
MAIN REF
LOCK
RE
-
CLK REF
CLOCK IN
32.0
48.0
DoP
AUDIO
HOLD
44.1
DSD
88.2
64
128
96.0
176.4
192.0256
1
–
10.0M