Goldmund TELOS 500 User manual

USER MANUAL
GOLDMUND TELOS 500
Universal Power Amplifier

Thank you for purchasing the GOLDMUND TELOS 500.
You have acquired the best Universal Power Amplifier ever made for professional and
domestic uses.
Please take some time to read this manual. It will provide you with useful information to
make your pleasure of listening to the TELOS 500 even higher.
INTRODUCTION
GOLDMUND TELOS 500 Universal Power Amplifier
Goldmund was founded in 1978 and has ever since been dedicated to the accurate
reproduction of sound and image.
At Goldmund, we strive to lead in the creation, development and manufacture of the
industry’s most advanced technologies, including audio and video systems, home -
networking and music distribution.
The guiding principle at Goldmund is to produce a precise sound with the least possible
loss of quality through the different stages. Goldmund will never adopt a technology before
it is sufficiently developed to satisfy the high quality standards we set. This is why
Goldmund has often rejected mainstream technologies and developed its own.

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Table of Contents
1 UNPACKING 5
2 AMPLIFIER LOCATION & COOLING 6
3 LINE VOLTAGE ADJUSTMENTS 7
4 CONNECTIONS 8
5 AMPLIFIER CONTROLS 9
6 SOUND QUALITY OPTIMIZATION 12
7 SAFETY FEATURES 14
8 MAINTENANCE 16
9 TECHNICAL SPECIFICATIONS 16

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W A R N I N G !
No connection or manipulation must be done
before reading these instructions. Damage to
the amplifier may result if the following
instructions are not consciously understood
and applied.
These extremely high quality amplifiers
possess new technical features which are a
necessity for accurate sound reproduction in
the best audio systems.
Only careful installation and use can provide
the satisfaction you are expecting.
The installation instructions must be carried
out in full and the mentioned precautions
taken to get the expected result and to avoid
impairing the amplifier’s performance.

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1 UNPACKING
You will find in the GOLDMUND TELOS 500 box:
- The amplifier
- The power cord
- This manual
ATTENTION
IF YOU NEED TO RETURN THE TELOS 500 TO THE FACTORY OR TO YOUR LOCAL
REPRESENTATIVE FOR A WARRANTY REPAIR, PLEASE NOTE THAT IT MUST BE
REPACKED IN THE ORIGINAL PACKAGING.
THIS PACKAGING HAS BEEN DESIGNED SPECIFICALLY TO PROTECT YOUR TELOS
500 IN TRANSIT.
USE OF ALTERNATIVE PACKAGING IS LIKELY TO RESULT IN DAMAGE,
INVALIDATING WARRANTY COVER.
Please keep the packaging in case you need to transport the amplifier at a later date.

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2 AMPLIFIER LOCATION & COOLING
The GOLDMUND TELOS 500 amplifier as all high quality amplifiers generates a large
amount of heat when driven at high levels and must be vented properly. It is mandatory to
allow a proper cooling of the heat sinks. Do not put temperature sensitive equipment on top
of the amplifier.
Due to its weight, and to maximize the effect of the built-in "Mechanical Grounding"
construction, the TELOS 500 is better located on the floor. Other very strong supports can
be used if they offer rigid transmission to the floor.
The TELOS 500 is built on four very hard conical feet to ensure proper vibration
transmission to the amplifier support. This evacuates all detrimental vibrations inside the
amplifier, following the famous GOLDMUND "Mechanical Grounding" principle.
If you use more than one TELOS 500 at any location, you may decide to stack them. Be
careful that the conical feet of the top amp are inserted properly on the top of the steel bars
of the amplifier located below. You may stack up to 3 amps provided extra care is taken to
ensure proper air circulation vents the rear heat-sinks.
Depending on the flatness of the surface where the amplifier will be located, you will adjust
the four round flat feet of the amplifier to allow full contact of the points with the support.

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3 LINE VOLTAGE ADJUSTMENTS
A voltage selector is provided inside the amplifier.
If your line voltage is not adapted to the voltage indicated on the serial plate of the
amplifier, please consult your local GOLDMUND dealer for internal adjustment.
ATTENTION
On the 220V configuration, the GOLDMUND TELOS 500 amplifier will function properly for
main line voltage between 211V and 257V. On the 110V configuration, the main line must
deliver between 105 and 129V. If your main line is usually out of these tolerances, please
consult your GOLDMUND dealer.
Please check the value of the main line fuse. This fuse is located on the back panel of the
amplifier, above the two power cord receptacles.
Use a 16A delayed fuse.

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4 CONNECTIONS
Connect the power cord to the back of the amplifier and plug it into the nearest wall plug.
Use only a 3 lugs grounded plug, for safety reasons. To get the best sound from the
amplifier, avoid any multiple plug or extension cord.
If used with an analog signal, connect the interconnect between the preamp and each
power amp and position the Analog/Digital input switch to analog. You may either use the
RCA female socket or the XLR. The XLR socket, especially useful in professional
installations, is wired as follows:
1. Grounding, Shielding
2. Hot
3. Cold
ATTENTION
If you want to use a symmetrical 4 wire cable, never maintain the ground/earth
switch to "Float" or you may damage your amplifier.
When used with a digital input signal, connect the digital input cable to the digital input and
switch the input switch to digital. Since a digital Spdif cable carries 2 channels you may link
the digital output to the next amplifier to transfer the second channel.
Connect the speaker cable to the red and black terminals in the back of the amplifier, or, if
you use a Goldmund High Definition speaker cable, you can connect directly from the
speaker cable to the coaxial plugs on the back panel of the amplifier, bypassing the
amplifier adapter module of the speaker cable.
The output (5 way post and coaxial) are connected internally in parallel.
They are provided to facilitate the connection in bi-wiring systems.
You may notice that the ground of the input plug and the black speaker terminal are the
same polarity. The amplifier is non-inverting in phase (see page 12).

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5 AMPLIFIER CONTROLS
As soon as the amplifier is connected to AC line and the amplifier has not detected an error
previously, the yellow light on the amp front panel is ON.
The TELOS 500 may be powered on either manually (Manual Operation) or automatically
when receiving a signal (Auto-Power Operation). This is selected internally by the small
white 10-position circular selector located on the top circuit of the amplifier, close to the big
capacitors.
There is one position for Manual Operation and 9 for Auto-Power Operation with various
delays to power a number of amplifiers without a big surge on the AC line.
Position 0: Manual Operation
Position 1: Power after 200ms
Position 2: Power after 400ms
Position 3: Power after 600ms
Position 4: Power after 800ms
Position 5: Power after 1s
Position 6: Power after 1.2s
Position 7: Power after 1.4s
Position 8: Power after 1.6s
Position 9: Power after 1.8s

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5 AMPLIFIER CONTROLS (Ctd.)
MANUAL OPERATION
On the front plate of the GOLDMUND TELOS 500 amplifier you will find only two POWER
keys.
In the Manual Operation mode, the two POWER keys have to be activated simultaneously
to power the amplifier on.
This security feature is provided to avoid accidental POWER ON or POWER OFF.
When the two keys are pressed simultaneously, the amp switches on in "Operating" mode
and the center green led lights on showing the amp is POWERED ON.
If the digital input is used, the yellow led may flicker, showing there is no lock and the
amplifier remains muted until a lock is found.
With an analog input, the amplifier is immediately operational.
By pressing the right key once, the amplifier is put in Mute mode, and the green led
flickers.
By pressing the right key once again, the amplifier returns to "Operating" state.
The amp may be POWERED OFF by pressing the two POWER keys simultaneously at
anytime.

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5 AMPLIFIER CONTROLS (Ctd.)
AUTO-POWER OPERATION
In AUTO-POWER mode, the amplifier is turned on automatically when receiving an audio
signal.
This mode is useful when several amplifiers are used together in a multi-amp system or
when the power amplifiers are not easily accessible.
When the amplifier is in AUTO-POWER mode and is operative, it may be muted by
pressing the right key, as in the normal mode.
OTHER DISPLAY
If an abnormal situation is found by the TELOS 500, one of the front panel red lights may
turn ON, and the power of the amplifier is instantaneously set OFF.
The left red led indicates an over temperature situation.
The central red Led indicates that HF oscillation or DC signal has been detected.
The right red Led indicates that the amplifier has detected an overload (for example when
output is short-circuited).
Before re-starting the amplifier, detect what caused the problem and remove the cause
first.
The amplifier will remain OFF with a red led on until the user intervenes.
To unlock the amplifier from one of the above status, press the 2 power keys
simultaneously. If the perturbation has been removed, the red led will stop and the yellow
led will glow again, the amplifier is now operating.

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6 SOUND QUALITY OPTIMIZATION
WARM-UP SONIC EFFECT
When the amplifier has not been used recently it will take 10 to 15 minutes for the amplifier
to reached optimum operating temperature, as the circuits have to warm up to around +55
degrees Celsius.
SPEAKER POLARITY
Even if you have a phase inverter on your preamplifier and have carefully selected the
proper line phase (see next paragraph below), there is a possibility to further increase the
sonic quality of your speakers by reverting the polarity of the speaker cable amplifier
termination. Line phase and speaker polarity interfere with each other however. We
therefore advise careful experimentation with all the combinations in order to arrive at the
best solution for your installation.
If your preamplifier has an absolute phase inverter, this will interfere too. If it has not, don't
forget the result will depend on the source, as most records and CDs have been recorded
without care for the absolute phase. Be patient…
MAIN LINE PHASE INVERSION
To select the proper phase, you have to select, by trying, one of the two power cord
positions.
We recommend that you proceed carefully when trying this. You must do it in combination
with the speaker polarity and/or with absolute phase switching to be sure of the result.

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6 SOUND QUALITY OPTIMIZATION (Ctd.)
THE GOLDMUND EXCLUSIVE "MECHANICAL GROUNDING”
In the GOLDMUND TELOS 500 amplifier, GOLDMUND has, as in other of its Ultimate Line
components, fully implemented an optimized vibration evacuation path. This is called by
GOLDMUND: "Mechanical Grounding". The perfect adjustment of this evacuation provides
the Telos 500 with an extraordinary dynamic capability and transparency, especially on low
efficiency speakers.
To get all the benefits of this design, the TELOS 500 must be located on a very rigid
support, or better directly on the floor, to be directly coupled with the building’s rigid
construction. Try various locations until you find the most rigid one. Avoid any decoupling
material, carpet especially, even between the furniture and the floor. Use the four pin-point
feet to couple the amplifier to the supporting furniture or to the floor.
With a very top system, the sonic improvement when the proper grounding is found is
obvious and worth the effort.

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7 SAFETY FEATURES
The GOLDMUND TELOS 500 amplifier provides sophisticated features to protect the
amplifier and the speakers against all mishandling or component failure. However
precautions must be taken to avoid problems with a very high power amplifier.
PROTECTION AGAINST DC
The TELOS 500 is a DC-coupled amplifier. If the associated preamplifier is badly designed
or defective (often true for the tube preamplifiers), the speakers could be damaged.
In such a case, the DC protection circuit of the TELOS 500 will automatically turn off the
amplifier. This detection circuit is totally immune to any sonic effect.
To indicate that the amplifier has been turned off by the protection circuit, a red led will be
displayed on the front panel.
When the source of DC offset is suppressed, turn ON the amplifier again.
PROTECTION AGAINST HF OSCILLATIONS
In the same way, the speaker must be protected against a large amount of high frequency
oscillation, if present, before and after to avoid any danger for the tweeters, even if these
frequencies remain unnoticed.
The amplifier is by itself extremely stable. However some mishandling must be avoided in
order to avoid any oscillation:
• Never plug an input cable into a power amplifier when it is turned on.
• Be careful to use only very high quality interconnects. If the ground connection
becomes loose, there is a big danger of oscillation. Warranty is voided if this occurs.
• Never run the input and output (speaker) cables in parallel.
If the TELOS 500 detects excessive oscillation, the amplifier will be turned OFF
automatically. You will have to suppress the source of oscillation and turn it ON again once
the protection is activated.

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7 SAFETY FEATURES (Ctd.)
OVERHEATING PROTECTION
If for any reason (malfunction, too high level, too low load impedance) the temperature of
the amplifier could reach a dangerous level, the TELOS 500 could be damaged.
To avoid this type of damage, if the temperature rises too high, a protection circuit switches
the amplifier OFF automatically. A red front panel light indicates that the amplifier has been
turned OFF by the protection circuit.
If this happens, let the amplifier cool for some time. We strongly recommend investigating
the cause of the temperature gain before operating the amplifier again.
PROTECTION AGAINST SHORT-CIRCUITS
If one output is short-circuited by accident and the current becomes too high, the TELOS
protection circuit may be activated.
In such a case the Overload red led on front panel will turn on.
First carefully check why the overload occurred and remove the cause.
Then switch the power ON if the short-circuit has been detected and removed.
To avoid Overload occurring, always switch OFF the amplifier before trying any
manipulation of the speaker cables.
There is no risk to leave the speaker terminals unconnected when the amplifier is ON.

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8 MAINTENANCE
The GOLDMUND TELOS 500 amplifier usually requires no maintenance.
Always turn the power OFF before cleaning your amplifier. Use a clean, soft, damp cloth to
clean the amplifier surface. Dampen the cloth with water or a mild detergent solution.
Avoid abrasive or harsh cleansers (eg. products containing sodium carbonate).
9 TECHNICAL SPECIFICATIONS
POWER SUPPLY
•Nominal Line Voltage 117 ; 234V
•AC line range: 10%
•Fuse 16A for 115 and 230V
•10 toroidal transformers
•Separated ground and earth signal
•Connection between earth and ground to cancel all ground loops
Rated power consumption:
•IEC 60065, 1/8 Output Power at 8 Ω: 210 W
Max power consumption:
•IEC 60065 at 8 Ω/1% THD: 550 W
FRONT PANEL
•2 control keys
•Red led display for Over-heating, DC offset or HF protection and Overload
•Green led display for Power ON, operating mode
•Yellow led display for AC line connection and digital Lock
•Yellow led display for Standby Mode

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9 TECHNICAL SPECIFICATIONS (Ctd.)
REAR PANEL
•Power cord: universal socket 3 lugs
•Main fuse (16 A slow-blow)
•Green-yellow AC earth binding post
•Output speaker 1 x 5 ways post
•Output speaker 1 x coaxial connector
•Analog Input connector RCA
•Input connector XLR for analog balanced input
•Digital input and output RCA connector
INPUT
Max level before clipping:
•Analog input: 1Vrms
•Digital input: - 6 dBFS
OUTPUT
Max level before clipping:
• 1 % THD, unloaded: 153 Vpp
PERFORMANCE
Output power:
•Power RMS (Goldmund FPP Standard): 350 Wrms on 8 Ω.
•Maximum power (IEC60065): 335 Wrms on 8 Ω/ 1%THD
Bandwidth:
•20Hz - 20KHz: +/-0,03dB, unloaded
•+/- 3dB: 0Hz to 100 kHz (limited by protection circuitry), unloaded

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9 TECHNICAL SPECIFICATIONS (Ctd.)
Slew rate:
•Unloaded,18V/µS
Distortion:
•IMD (SMPTE), unloaded: < 0.03 %
•THD+N, unloaded: < 0.06 % from 20 Hz to 20 kHz at 20 Vrms output
Output noise floor:
•Analog input terminated with RCA Shorting Caps, unloaded: < 3 µV from 20 Hz to 20 kHz
Gain:
•35dB
Dynamic range:
•22 kHz measurement bandwidth (flat), true RMS unloaded: 110 dB
Damping factor:
•380 at 1 kHz / 8 Ω
DIMENSIONS
•330 W x 470 D x 270 H (mm)
WEIGHT
•Weight: 55 kg
WARRANTY
•3 years parts and labor
Note:
Information and product specifications
contained in this manual are subject to
change without prior notice. Updated
versions of this manual will be posted on our
website at www.goldmund.com.
Please visit our support page at
http://www.goldmund.com/support/register to
register your Goldmund product for
warranty.
RevA