To reduce the risk of fire or electrical shock, do not expose this
device to rain or moisture,
direct sunlight or excessive heat from sources such as radiators or spotlights. There are no user-serviceable parts inside.
Any repair and maintenance may only be carried out by qualified personnel authorized by MUTEC GmbH. The device was
designed for operation in a standard domestic environment.
Do NOT expose the unit and its accessories to rain, moisture,
direct sunlight or excessive heat produced by heat sources
such as radiators or spotlights! A free flow of air inside and in
close proximity to the unit must always be ensured.
Initial Operation
Prior to the initial operation of the device, the unit itself, its
accessories and packaging must be inspected for any signs of
physical damage that may have occurred during transit. If the
unit has been damaged mechanically or if liquids have been
spilled inside the enclosure, the device may not be connected
to the mains power or must be disconnected from the mains
immediately! If the unit is damaged, please do NOT return
it to MUTEC GmbH, but notify your dealer and the shipping
company immediately. Otherwise, any liability claims will not
be granted.
If the device is left in a low-temperature environment for a
long time and is then moved to a room-temperature environment, condensation may occur on the inside and the exterior
of the device. To avoid short-circuits and electric shocks, make
sure to wait one or two hours before putting the device back
into operation.
The unit must be grounded during operation! For information
on the power input module wiring, refer to the »Wiring of
connectors« section in the appendix. Disconnect the device
from the mains when not using it for an extended period!
Trademarks
MUTEC GmbH assumes no liability for any incorrect information provided in this manual. Please note that all software/
hardware product names are registered trademarks of their
respective owners. No part of this manual may be reproduced,
copied or converted to a machine-readable form or electronic media without written permission by MUTEC GmbH. We
reserve the right to change or improve our products without
further notice.
This symbol, a flash of lightning inside a triangle,
alerts you to the presence of non-insulated dangerous voltage inside the enclosure - voltage that
may be sufficient to constitute a risk of shock.
This symbol, an exclamation mark inside a triangle
alerts you to important operating or safety instructions in this manual.
Declaration of Conformity
We herewith confirm that this product complies with the
European Commission’s standards on electromagnetic
compatibility.
Power Supply
The device contains a self-adapting, wide-range power supply
supporting the majority of global standard line voltages within
a range of 90-250 V, with no need for any user adjustments.
Make sure that your line voltage source provides a supply voltage within the specified range. In addition, make sure that
the device is properly grounded via the local electric installation. Please use the enclosed power cable (see packaging)
to connect the unit to the mains power. Switch the unit off
before you attempt to connect it to the mains. Firstly, connect
the power cord to the device, then to a standard 3-pin mains
outlet. To remove the power cord never pull on the cable but
on the mains plug!
4
Interference emission:
EN 50081-1, 1992, Resistance to interference: EN 50082-1,
1992. Presupposed as operation condition is that all signal
outputs are connected with
high-quality and well shielded
cables.
Page 5
Warranty Regulations
§1 Warranty
MUTEC GmbH warrants the flawless performance of this product to the original buyer for a period of three (3) years from
the date of purchase. If any failure occurs within the specified
warranty period that is caused by defects in material and/or
workmanship, MUTEC GmbH shall either repair or replace the
product free of charge within 90 days. The customer is not
entitled to claim an inspection of the device free of charge
during the warranty period. If the warranty claim
proves to be justified, the product will be returned freight
prepaid by MUTEC GmbH within Germany. Outside Germany,
the product will be returned with the additional international freight charges payable by the customer. Warranty claims
other than those indicated above are expressly excluded
§2 Warranty Transferability
This warranty is extended exclusively to the original buyer
who purchased the product from a MUTEC GmbH specialized
dealer or distributor, and is not transferable to anyone who
may subsequently purchase this product. No other person (retail dealer, distributor, etc.) shall be entitled to give any warranty promise on behalf of MUTEC GmbH.
(e.g. displays, LEDs, potentiometers, faders, switches, buttons, connecting elements, printed labels, cover glasses,
cover prints, and similar parts)..
Functional failure of the product caused by improper
•
installation (please observe CMOS components handling
instructions!), neglect or misuse of the product, e.g. failure
to operate the unit in compliance with the instructions
given in the user or service manuals.
Damage caused by any form of external mechanical
•
impact or modification.
Damage caused by the user’s failure to connect and ope-
•
rate the unit in compliance with local safety regulations.
Damage caused by force majeure (fire, explosion, flood,
•
lightning, war, vandalism, etc.).
Consequential damages or defects in products from other
•
manufacturers as well as any costs resulting from a loss of
production.
Repairs carried out by personnel which is not authorized
•
by MUTEC GmbH.
§5 Repairs
§3 Warranty Regulations
The return of the completed registration card, or online registration on one of the websites specified below, is a condition
of warranty. Failing to register the device before returning it
for repair will void the extended warranty.
The serial number on the returned device must match the one
stated on the registration card or entered during online registration. Otherwise, the device will be returned to the sender at
the sender’s expense. Any returned device must be accompanied by a detailed error description and a copy of the original
sales receipt issued by a MUTEC dealer or distributor.
The device must be returned free of shipping expenses and in
the original package, if possible; otherwise, the sender has to
provide comparably protective packaging. The sender is fully
responsible for any damage or loss of the product when shipping it to MUTEC GmbH.
§4 Limitation of Warranty
Damages caused by the following conditions are not covered
by this warranty:
Damages caused by every kind of normal wear and tear
•
To obtain warranty service, the customer must call or write
to MUTEC GmbH before returning the unit. All inquiries must
be accompanied by a problem description and the original
buyer’s invoice. Devices shipped to MUTEC GmbH for repair
without prior notice will be returned to the sender at the sender’s expense. In case of a functional failure please contact:
MUTEC Gesellschaft für Systementwicklung
und Komponentenvertrieb mbH
Siekeweg 6–8, 12309 Berlin, Germany
Phone: +49 (0)30 746880-0
Fax: +49 (0)30 746880-99
E-Mail: tecsupport@mutec-net.com
Web: www.mutec-net.com
5
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REF 10
Introduction
General Description
Thank you very much for your purchase of the MUTEC REF 10,
an audiophile 10 MHz reference master clock generator.
The REF 10 is an audiophile reference master clock generating
10 MHz signals with industry-leading low phase noise (i.e. jitter) to significantly improve digital playback systems. As the
conductor of your digital audio orchestra at home, the REF
10 will inspire you with unheard-of clarity, graceful dynamics,
and pure music. It is also the most flexible, most compatible
10 MHz clock on the market allowing you to spend less time
worrying about integration and leaving you with more hours
to enjoy blissful playback.
In contrast to so-called “atomic clocks”, clocks based on a
rubidium or cesium normal, the REF 10 is engineered around
MUTEC's handcrafted, oven-controlled oscillator (OCXO)
made in Germany, featuring significantly higher clock stability in the time domain relevant for audiophile digital audio
performance. Newly developed ultra-low noise clock distribution and amplification circuits based on sub-1 Hz optimized,
lowest noise voltage sources transfer the reference signal to
the REF 10's eight outputs with virtually no losses.
As a result and unlike any other currently available reference
generator the REF 10 fulfills both of the critical requirements
for an extraordinary audiophile reference master clock:
Generates a very high slew-rate square wave signal for
•
superior lock precision compared to the sine wave signals
used by competing brands
Provides simultaneous reference outputs with 50 and 75
•
Ω impedance for maximum compatibility with clocks and
DACs by other manufacturers
Integrated, highest-quality international linear power
•
supply
Intuitive user interface with noble aesthetics
•
Rack-mountable with optional mounting brackets for
•
studio use (2 RU)
Matching MUTEC Products
MC-3+ Smart Clock
•
The MC-3+ Smart Clock is an audio re-clocker and master
clock that can enhance digital audio devices in two ways:
by providing low-jitter clock signal for external synchronization and by aggressively re-clocking using MUTEC’s
REVIVE technology.
Lowest possible phase noise for unmatched audio
•
Highest clock precision for most accurate synchronization
•
Due to its revolutionary clock reference and its unrivaled flexibility the REF 10 can enhance the audio quality of compatible
D/A converters (DACs), music servers, and re-clockers to the
highest possible level. Unlock a more dynamic, more transparent sound stage with exceptional spatiality and level of
detail, free from any digital blur. As the quasi conductor of
your digital audio orchestra at home, we are sure the REF 10
will inspire you with unheard-of clarity, graceful dynamics,
and pure music!
Features
Audiophile 10 MHz reference generator with industry’s
•
lowest phase noise
Improves and enhances compatible DACs, audio re-clo-
•
ckers, music servers, and master clocks
Engineered around a handcrafted, ultra-low phase noise
•
OCXO made in Germany
Revolutionary, sub-Hz optimized, lowest noise power
•
supply for every circuit section
MC-3+ Smart Clock USB
•
As the successor of the MC-3+ Smart Clock , the MC3+USB offers significantly improved audio performance
and additionally acts as an isolating USB interface for
audio computers and music servers.
iClock & iClock dp
•
iClock and iClock dp are both synchronizable, highest
precision clock synthesizers with extremely low jitter
for applications in audio/video production studios and
broadcast.
Accessories
MW-07/19: rack mount kit consisting of two mounting
•
brackets for installing the REF 10 in 19” racks (item no.
8020-046).
6
Page 7
Product Registration for Warranty and Support
We kindly ask you to register your MUTEC product through
our website immediately after buying. This ensures full warranty services over a period of three years after purchasing
the product. Additionally, we provide free technical support
for all registered products. We will also inform you about new
products and product updates (you may opt-out at any time
of course).
Please register your product at:
www.mutec-net.com > Service > Product Registration
Or for direct access type in the following URL into your
browser:
Your REF 10 was packaged carefully. Nevertheless we recommend checking the contents directly after opening the package:
1 x REF 10
1 x Power cable
1 x Manual
In the unexpected event that there are any visible damages
or missing items, please refer to the chapter »Safety Instructions« and »Warranty Regulations« for further details.
Placing the Device
The unit should be set up as closely as possible to the devices
to which it will be connected to avoid excessive cable lengths.
The four custom-designed case feet include a rubber ring protecting the ground’s surface from being damaged and reducing any structure-borne vibrations interfering with the unit.
It is recommended to keep the device away from vibrating or
mechanically moving devices in close proximity.
The device can be mounted into a standard 19“ rack and will
require 2U (rack units). Therefore, we offer an optional rack
mounting kit called MW-07/19. This includes two rack brackets which need to be screwed to each side of the device‘s
case. Before mounting the device into a 19“ rack, please unscrew the four rubber feet with a suitable screwdriver. Install
the device so that 1U of rack space is left open both above
and below the device to allow for sufficient ventilation! For
extra secure installation we further recommend an additional
rack mounting plate that will prevent any long-term mechanical deformation of the enclosure.
Attention
Before installing the unit the section Safety Instructions
located at the beginning of this manual should be read
carefully! Never expose the device and accessories to
rain, moisture, direct sunlight, or excessive heat produced by radiators, heaters, or spot lights! Sufficient
air circulation in the proximity of the device must be
ensured!
Interface Connections
There are two standards with respect to interfaces and cable
termination for 10 MHz reference signals:
50 Ω impedance termination
•
This standard can commonly be found among units by
Japanese Hi-Fi manufacturers, and for measurement
devices in laboratory applications.
75 Ω impedance termination
•
This termination is more common for devices used in
recording, mixing and broadcast studio applications.
For audiophile Hi-Fi and high-end consumer audio applications
both standards are currently in use by different manufacturers.
For this reason, the REF 10 provides clock outputs with both 50
and 75 Ω termination that can be used simultaneously.
Transferring clock signals with 50 Ω termination is typically
done with coaxial cables according to the RG-58/U standard.
However, we recommend using cables manufactured to the
RG-400/U or CLF200/HDF200 standards, because they are
double-shielded and offer reduced attenuation in contrast to
the RG-58/U norm. Cables specified as CLF200/HDF200 further
feature a stronger inner copper conductor.
For clock signals with 75 Ω termination it is common to use
coaxial cables specified by the RG-59/U and RG-598/U standards. As an alternative, we recommend using cables manufactured to the RG-216/U standard, which are usually also
double-shielded, feature reduced attenuation, and a stronger
inner conductor.
A wide range of coaxial cables with BNC connectors and the
appropriate termination by specialized manufacturers are available at Hi-Fi retailers. Depending on their price range they are
manufactured using premium materials and will have superior transfer characteristics than the aforementioned standard
cables.
All interfaces of the devices in a given setup need to be properly connected with each other. Always ensure that the clock
output of the REF 10 are connected to an appropriate input
of the receiving device. Make sure that the clock input of the
receiving device has the correct internal impedance termination. This internal termination can sometimes be adjusted via
an external switch on the device or via a software setting. We
recommend double-checking the operating manual of any
device that you are planning the REF 10 to be connected to.
A mismatched termination of the system will cause losses in
signal quality and clock precision!
8
Page 9
We further recommend keeping the cable lengths as short as
possible to minimize signal losses and interference. Cables at
0.5 m, 1 m, or a maximum of 2 m length are ideal. The longer
the cable needs to be, the higher the quality should be to avoid
excessive losses!
Useage of so-called BNC tee adapters
BNC tee adapters are often used to daisy-chain clock signals
between several devices. Usually this is necessary if the clock
master does not provide a sufficient number of clock outputs.
Since the REF 10 generates exceptionally low phase noise, i.e.
highest quality signals, any additional elements in the signal
path can have an attenuating effect that negatively affects the
crucial slew rate of the signal. Consequently and considering
that the REF 10 provides a total of eight clock outputs we
advise against daisy-chaining 10 MHz clock signals.
Any device that is supposed to be clocked by the REF 10 and
benefit from its audiophile performance must be connected to
a dedicated clock output!
9
Page 10
REF 10
Control Elements and Terminals
Front Panel
Rear Panel
4
35
212134
1) »POWER«
This red LED illuminates when the device has been powered
up. First engage the rear panel power switch next to the mains
terminal. Always ensure the appropriate choice of line voltage
»115 V / 230 V«! Then, depress the front panel power switch
and the red LED will light up.
2) »OUTPUT SELECT«
This combined push button rotary encoder is used to select
the individual outputs and to disengage or re-engage them.
3) »LEDs 1 – 8«
These eight white LEDs represent the eight rear panel clock
outputs and reflect if the respective output has been turned
on or off. An illuminated LED means the output is active, i.e on.
4) »OSCILLATOR«
This blue LED reflects the status of the oscillator heat-up process. Upon powering the device up this LED will be flashing
until the oscillator has reached its correct operating temperature. Once the temperature has been established, the LED will
be permanently lit.
1) »50 , Outputs 1 – 2«
These two clock outputs are equipped with a 50 Ω termination. Use only BNC cables with the appropriate 50 Ω impedance with these outputs.
2) »75 , Outputs 3 – 8«
These six clock outputs are equipped with a 75 Ω termination. Use only BNC cables with the appropriate 75 Ω impedance with these outputs.
3) »110/120 V & 220/240 V«
This is is the line voltage selector that also serves as the holder
for the mains fuse.
Attention
It is imperative to make sure the proper line voltage has
been selected prior to powering up the device for the
first time!
Information on how to change the line voltage can be
found in the chapter “Changing the line voltage” on page 15 in the appendix.
4) Mains Connector
Connect the supplied IEC power cable here. Make sure that
the power switch is turned off before connecting the device
to your power source.
10
5) Mains Power Switch
The mains power switch engages the power supply for the
device. Do not turn the unit on before completing the wiring
and installation, particularly with respect to the choice of line
voltage according to you country’s power grid. Please make
sure to read the safety instructions at the beginning of this
manual!
Page 11
Operation
General System Operation
Operating the REF 10 is very straight-forward! Apart from the
two power switches there is only a single push button rotary
encoder (»OUTPUT SELECT«) used to individually turn the
eight outputs on or off. Per factory default all outputs are active upon powering up the device for the first time, so all eight
white front panel LEDs will light up accordingly!
Selecting and toggling the outputs
The front panel encoder’s action is stepped and each step will
evoke a new setting. The push button function of the encoder
is used to toggle features.
Rotate the encoder by one step to select an output and the
first LED will start flashing. Turning the encoder by another
step now will cause the next LED to flash while the previous
one returns to a steady light. Thus, it is only possible to select
one output at a time.
As long as an LED is flashing, the respective output can be
toggled with a push of the encoder. When the LED is on, the
output is active. When the LED is off, the output has been disengaged. Any setting will have immediate effect - it is not
necessary to take any further actions.
The last setting of the REF 10 will be stored and preserved
after the the device has been powered down.
The REF 10 should always be placed away from mecha-
•
nically vibrating devices (such as turn tables). Although
the REF 10’s case feet of the are equipped with isolating
rubber rings, excessive structure-borne vibrations can
nonetheless interfere with the oscillator and negatively
affect the clock performance and signal quality.
The REF 10 should furthermore not be placed in close proximity to devices emitting strong electromagnetic fields
(such as fluorescent lamps). Even though the electronics
of the REF 10 are encapsulated in a steel enclosure these
strong electric fields can interfere with the sensitive electronics and also negatively affect the signal quality.
We generally recommend disengaging all clock outputs
•
that are not used for your given setup to reduce potential
interference as much as possible. Additionally, unused
and disengaged outputs can be fitted with so-called BNC
caps. These are available from various retailers and can be
used regardless of the termination impedance of the REF
10's outputs. The use of so-called BNC terminators is not
necessary to protect the outputs.
Recommendations for the REF 10
To ensure a long-lasting performance with optimum clock signal quality that will best enhance your connected devices
we would like to share a few recommendations for using the
REF 10.
First customers have told us that for best sound perfor-
•
mance of the connected devices it is useful to let the REF
10 burn-in for approx. 14 days. Thus, we recommend to
leave your REF 10 switched on for that period of time.
Prior to enjoying an in-depth listening session we recom-
•
mend pre-heating the REF 10 for about 20-30 minutes.
While the heater generally reaches its operating temperature in about one minute, the entire oscillator section
takes longer to fully warm up. To ensure optimal performance and highest frequency stability, you should grant
the REF 10 this additional warm-up time.
Keeping the REF 10 permanently powered up is generally
•
not required as long as you observe the extended warmup period described above. We do however advise against
power cycling the REF 10 in short, repeated intervals!
11
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REF 10
Applications
Using the REF 10 With Other Products
This chapter serves to illustrate several possible applications for the REF 10 and will help you achieve the best possible sonic
results. In general, the REF 10 can be used for the following applications:
As an audiophile performance enhancement for compatible DACs, master clocks, and audio re-clockers.
•
As an ultra-low noise, high stability clock reference for the entire digital audio chain at home or in the studio.
•
As an ideal high-end upgrade for MUTEC’s own MC-3+, MC-3+USB, and iClock/iClock dp master clocks.
•
To stabilize existing audio clock generators.
•
To explain these applications it is important to understand that the REF 10 is a reference master clock exclusively generating highest quality 10 MHz clock signals. Compatible devices can use this ultra precise reference clock signal to perform their own signal
processing with more accuracy and fewer errors, yielding a better sound quality. It is crucial to understand that these 10 MHz
clock signals are entirely independent from the audio clock (typically 44.1 kHz up to 192 kHz) of the playback! As a consequence,
the REF 10’s clock signal is not compatible with the common Word Clock audio clock that is also transmitted via 75 Ω BNC cables.
There are two possible routes to harness the superior clock precision of the REF 10 in your digital audio system:
You have a DAC, network bridge, streamer or audio re-clocker with its own 10 MHz compatible input.
•
You have an audio master clock that can take the 10 MHz clock from the REF 10 and convert it into standard a Word Clock
•
audio clock to be distributed to other devices.
The simplest possible application for the REF 10 would look like this:
Thanks to a total of eight clock outputs on the REF 10 any 10 MHz compatible device in a setup can and should receive its own
dedicated clock supply. We strongly advise against daisy-chaining multiple devices using so-called BNC tee adapters (more about
this on page 9).
Particularly the combination of the REF 10 with MUTEC’s own MC-3+ and MC-3+USB Smart Clocks offers exciting applications to
achieve the best-possible quality enhancements by re-clocking digital music sources. To understand this scenario, please imagine
the following setup as a starting point:
12
Page 13
In this application example we have several digital sources on the left that are used to play back music via several digital interfaces (e.g. AES3, S/P-DIF or USB). The MUTEC MC-3+ or MC-3+USB act as audio re-clockers to enhance the music signal and
remove jitter before passing the signal on to the DAC (d/a converter) and the loudspeakers. This is a simple closed system in which
the audio clock rate is determined by the music source. All other devices following in the chain (audio re-clocker and DAC) will
adapt to the sampling rate set by the source.
This particular system can be enhanced by the REF 10 in up to three places, depending on how many of the digital devices offer a
10 MHz compatible input. In the best possible case, all of the digital sources (e.g. BlueRay player, streamer, network bridge), the
audio re-clocker, and the DAC can receive their own 10 MHz clock supply from the REF 10.
It is helpful to understand that the hierarchy with respect to the audio clock (i.e. the sampling rate) of the system remains unchanged. The 10 MHz signal from the REF 10 is strictly used to enhance the performance of the connected devices and does not
make changes to the audio clock of the system. The sampling rate of the system is still determined by the music source, which is
important to know when playing back playlists with mixed sampling rates.
Of course this application example is also conceivable without using an audio re-clocker between the digital sources and the
DAC. In this case, the REF 10 can still yield a significant improvement in sound quality, as long as at least one of the other devices
is equipped with a 10 MHz compatible clock input.
To help you getting started in the “10 MHz” universe we have put together a comprehensive list of currently available 10 MHz
compatible devices.
Disclaimer: Compatibility of the REF 10 with the above listed products is assumed based on the specifications published by the respective manufacturers and subject to change.
MUTEC is not liable for compatibility issues with third-party products operating outside of industry standards.
HD-7A50DAC
DSP-010EX, DSP-030EX50Network Player, DAC
DSP-04EX50DAC
75Audio Clock Generator
Audio Re-Clocker, -Clock Generator,
USB Interface
14
Page 15
10 MHz Compatible Products
ManufacturerProductImpedance (Ω) Type
SOtMsMS-1000SQ (with sCLK-EX Expansion)50/75Musik Server
sMS-200ultra (with sCLK-EX Expansion)50/75Network Player
Disclaimer: Compatibility of the REF 10 with the above listed products is assumed based on the specifications published by the respective manufacturers and subject to change.
MUTEC is not liable for compatibility issues with third-party products operating outside of industry standards.
15
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REF 10
Appendix
Changing the Line Voltage
Fuse HolderTriangles
Always unplug the mains cable before changing the line
voltage fuse!
On the left hand side of the mains power module on the rear
you will see two small triangles facing each other (see left
arrow in picture above). The respective line voltage »110-120
V« or »220-240 V« is printed above the right triangle. If this
setting should not be appropriate for your power grid, the fuse
holder (see right arrow in picture above) needs to be pulled
out, rotated by 180° around its own axis, and be put back in
place. You should then see that the triangle now indicates the
correct line voltage. It is easiest to remove the fuse holder by
inserting a small flat screwdriver in the groove on the right
side of the fuse holder to pull it outwards.
Make sure that the fuse holder is properly seated in its
housing with its top flush to the power!