Adjustments :
The input selector switch chooses the asymmetrical inputs as well as the symmetrical inputs.
The selected input is indicated on the display at the ront panel.
By pushing the button "on-o ", the preampli ier is connected to the power supply via relays,
the red LED turns o and the display is illuminated.
The button "mute" clears the inputs and outputs, the button is cleared as soon as the writing
"MARCONI" on the display ades and the input and level settings are shown.
To protect the power ampli iers and loudspeakers, the DC-o set at the outputs is measured
and switches the outputs o , when a certain level is exceeded. In that case the display
shows –DC-O set-.
Please allow some minutes o burn in a ter switching on, to prevent the DC-sensors to
switch o because o some slowly reducing DC rom the tube stages. Avoid to raise the
volume control to high volumes during that time.
Setup :
First all needed inputs and outputs should be plugged in and the preampli ier be connected
to the power supply be ore this is connected to the mains. It is essential o being care ul not
to create a short circuit, because a (lasting) short circuit can lead to damages in the
preampli ier (i.e. take o short circuit bridges at symmetrical power ampli ier inputs when
connected symmetrically).
In order to connect the preampli ier to the mains, the power supply has to be plugged into a
socket or a multiple plug with double poled power switch.
The mains-plug has a red mark on one side, the terminal at this side should be connected to
the hot pole o the mains to get the best sound quality.
The LED at the ront panel o the power supply starts to glow when the power supply o the
preampli ier is connected to the mains. The power supply needs a minimum o current when
the preampli ier is switched o , only the micro-controller o the preampli ier is still under
current.
The preampli er should be placed on its granite base as ar away as possible rom power
supplies, (magnetic ields, humming).
The granite base can be equipped with elt gliders or spikes to improve the setup.
The tubes have a normal li e span o aproximately 10 years. I they have to be changed, they
should be replaced only by a complete set o the original tubes. The tubes used in this
preampli ier are specially selected and matched or their purpose. They can be ordered as a
whole set rom the manu acturer by giving the preampli ier serial number. A special tool is
needed to replace the tubes.
