Margules ACRH-3, Owner'S Manual

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ENGLISH - 20
RECOMMENDATIONS
Do not substitute 12AU7 tubes with a different type
because this could increase distortion.
To change the tubes, they must be removed by slowly
pulling them upwards with gentle lateral movements.
They should not be removed abruptly, as ceramic
sockets with gold-plated connectors could be damaged.
Do not remove the tubes from the circuit while the
equipment is connected to the power supply.
The useful life of tubes may last several years under
normal use conditions (two hours per day); however, for
an optimal performance of the amplifier, we suggest
changing the tubes every two years.
Avoid the use of long interconnect cables (longer than
10m), between the line level sources and the ACRH-3
since this may induce noise into the signal.
Avoid the use of long interconnect cables (longer than
1.5 meters) between the turntable and the ACRH-3 since
this may induce noise into the signal.
Verify that the turntable’s ground wire is properly
shielded and connected to the ACRH-3, using the
ground screw located at the back of the unit to do so.
Verify that the turntable’s cable, as well as the
interconnect cables between the ACRH-3 and the line
level sources are nowhere near AC power sources, such
as wall outlets, power supplies, power distributors,
power cables, transformers of other electrical devices,
or speaker cables.
Never wind, twist, or twine the turntable’s cable or the
interconnect cables.
Always use high-quality end to end isolated and
shielded cables in order to avoid noise induction that
may interfere with music reproduction.
Since the preamp stage uses tubes for its operation,
avoid connecting equipment with a low impedance load
(less than 100 KΩ).
The quality as well as the DC offset in the AC powerline
are important to avoid any mechanical noise induced by
the transformers.
Placing the amplifier on vibration dampening or isolation
devices (spikes) usually helps to improve the
instrumental detail. The ACRH-3 is an equipment
sensitive to small adjustments, therefore we recommend
the use of high-quality cables as well as firm amplifier
stands.
TROUBLESHOOTING
1. The amplifier does not turn on:
•
Verify the equipment is correctly connected to the
mains power or AC power source.
•
Check the electrical supply input fuse located at the
back of the amplifier. If it is damaged, replace it by one
that meets the correct specifications.
If the fuse blows again, directly contact our technical
support department.
2. The amplifier turns on but it no sound is heard:
•
Verify the source cables as well as the speakers’
cables are properly connected to the terminals on the
amplifier.
• Verify the source selector is placed at the position
corresponding to the right source.
• Verify that the bridge or jumper connecting the
preamp output and the amplifier input is correctly
installed.
3. One of the channels does not emit sound:
•
Verify that the cables of the sources, as well as
those of the speakers, are properly connected to the
terminals on the amplifier.
•
Check that the LED indicators at the base of the
preamp tubes are on.
If the LED indicator do not light up, replace the tubes.
•
Check the fuse corresponding to the channel that
does not emit sound, which is located at the back of the
amplifier (near the speakers’ terminal).
In case the fuse is blown, replace it by one that meets
the correct specifications.
4. More than one source indicator
is lit :
• Restart the unit by unplugging it from the AC power
source and plugging it in again.
Resetting the system is necessary. To do this, turn on
the system using the input selector.