Studio Magazin

For a very long time, the Berlin-based di-
gital specialist Mutec has dedicated its-
elf with its products to the production,
conversion or distribution of digital au-
dio and clock signals. Until today Mutec
thereby avoided to foreground acoustical
factors and rather delivered more tech-
nically ‘clean work’ at the current state
of technology. This is fully intended as
a compliment. With the MC-3+ Smart
Clock, the manufacturer now presents
a master clock that generates on one
hand a particular ultra-low-jitter clock si-
gnal by a new process, that on this qua-
lity level enables on the other hand an
up to now peerless re-clocking of syn-
chronous or asynchronous digital audio
sources. The reasoning basis for a state-
ment about ‘sound quality’ is the Mutec-
developed 1G-Clock technology that of-
fers a clock signal quality at the bounda-
ries of what is technically feasible, the-
refore claiming the right for itself to set
the resulting sound of converters into
the focus.
Mutec‘s 1G-Clock
With a base clock in the 1 GHz range,
Mutec makes use of an extremely high
clocked DDS-frequency-synthesis process
(Direct Digital Synthesis) that proceeds
on an elaborately determined ‘special
frequency’ which also varies in the range
of the base clock. As the company found
out, the DDS process generates the by
far lowest jitter and noise values at ex-
actly this frequency. If one deviates from
this frequency, the jitter measurement
values deteriorate significantly. As reaso-
nably well conceivable even to non-de-
velopers, such a construct reacts sen-
sitively so the manufacturer had to use
specially selected components for the
DDS’s loop-back filter. By using the la-
test extremely low-noise voltage sources
that particularly offer a very low noise
down to the low-frequency range, too,
the MC-3+ is actually on an extremely
current technological state. Nevertheless,
an outstanding audio quality can not on-
ly be explained by a high base clock alo-
ne. A lot more, the circuitry concept had
to be tuned very precisely particular-
ly in the context of the DDS process, the
clock base and the further clock distri-
butor stages. The components suitable
for this purpose were only found in the
course of extensive testing.
Overview
The MC-3+ Smart Clock is Mutec’s first
device which follows a new design line
with an in many ways optimized casing
design and a colour scheme, too. The
proven menu navigation from other de-
vice developments in the Mutec portfo-
lio was however thankfully retained. As
with most Mutec products, the electro-
nics are housed in an enclosure of a half
19 inch size. For the operation, the menu
structure follows a logical arrangement
of in groups combined function LEDs,
controllable with only two buttons (‘Me-
nu’ and ‘Select’). However, before we
delve into the details, some basic ob-
servations on the device have to be ma-
de. Although the possibilities of this ma-
ster clock generator and distributor are
actually more or less self-explanatory by
the front panel labeling and the rear in-
terfaces: the MC-3+ is, as already descri-
bed, a clock generator/distributor that
thanks to the use of new technologies
provides a high quality clock signal. Ho-
wever, it also offers the possibility of re-
clocking a digital audio signal by scan-
ning it with a high resolution and then
(if one may say so) ‘marrying’ the audio
data with a newly generated, almost jit-
ter-free clock signal to obtain an optimal
sonic representation of the audio sour-
ce. In the function of a clock distributor,
the device can synchronize to external
references such as a Word Clock or a 10
MHz signal of so-called ‘atomic clocks’
and GPS receivers or to an AES11 or S/P-
DIF audio signal. In the re-clocking ope-
ration, the MC-3+ receives digital audio
signals in the AES3 or S/P-DIF format.
The output interfaces at the rear corre-
spond to the arrangement of the front
panel function LEDs. It includes three
BNC-WCLK output pairs that are labeled
with A and B for a better overview or wi-
ring documentation. The S/P-DIF out-
put is outlined by a coaxial and an op-
tical connection. Output number five is
the AES3/11-XLR socket. On the front, all
five outputs are outlined by five rows of
clock multiplier LEDs which means that
different multiples of a basic frequen-
cy can be output up to a 256fold for ol-
der Pro Tools systems (the so-called Su-
per Clock). On the input side, an XLR
jack is provided for AES3/11 signals (de-
pending on the application). Additional-
ly, an S/P-DIF input with a coaxial or op-
tical connection, and a BNC-WCLK input