In case the fuse is blown, one of the tubes of that
channel has failed, so you should replace both
tubes.
Never replace these fuses by other of different
characteristics.
4.
The sound is distorted, or a humming
sound is heard (coming from one of the
channels only):
Check that the preamplifier cables as well
•
as the speakers' cables are properly connected
to the terminals on the amplifier.
Make sure the source of the signal is
•
operating correctly.
•
Verify the tubes are properly installed on
their sockets.
One of the tubes may be damaged.
•
In order to identify a defective tube, check that
the LED indicators of each tube are lit (after the
pre-heating period).
If a LED indicator is not lit, the corresponding
tube must be replaced (preferably, replace the
pair of output tubes that correspond to the same
channel).
If the four LED indicators light up, the problem
could come from one of the small-signal tubes
(12AU7).
To identify the damaged small-signal tube, you
must first interchange between channels the
two frontal tubes; if the problem persists,
interchange the back row tubes.
If the channel with the distorted sound changes
or "accompanies the tube" while performing the
interchange of the tubes' position, replace the
small-signal tube that is causing the distorted
sound.
ENGLISH - 23