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speakers, some users may prefer not to hear it. To avoid the sound, simply switch the M-3000 MK IIs to pentode
mode prior to turning them off (see the “On-the-Fly Triode/Pentode Switching section below).
In the case of any failure, please contact Your Allnic dealer for assistance.
“ON-THE-FLY” TRIODE/PENTODE SWITCHING
You can use the Triode/Pentode “Mode Selector” button at any time during operation to switch back and forth
from Triode to Pentode operation. Press the mode selector button down to have the M-3000 MK II operate in
Triode mode; press the button again so it is in the raised position to have the M-3000 MK II operate in Pentode
mode.
THE CURRENT METERS
These illuminated meters indicate the current supply to each of the four KT150 gain tubes in the M-3000 MK II.
There is one current meter for each KT150 power tube. There is also a potentiometer and a fuse for each KT150.
When you turn on the M-3000 MK II, the needle of each current meter should be between the two parallel lines on
the meter face. Any error of current supply to or failure of a KT150 tube is indicated by the needle on the KT150
tube’s respective meter moving out from between these two parallel lines.
TUBES AND TUBE BIAS
Each M-3000 MK II monoblock uses the following tubes:
•
Four (4) x KT150
•
Two (2) x E282F
•
One (1) x 5654
Because of the individual bias for each KT150, it is not necessary to use a matched quad of these power tubes in the
M-3000 MK II.
If the needle of a current meter for a KT150 has moved to the left of the parallel lines on the meter face, using an
appropriately bladed screwdriver, adjust the potentiometer directly in front of that tube’s location by turning it
clockwise until the needle has returned to between the meter’s parallel lines. If the meter needle has moved to the
right of the parallel lines on the meter face, turn the potentiometer control counter-clockwise to correct.
If a meter’s needle drops to the left limit of the meter’s face during operation, this indicates a failure of the related
KT150 tube. You must turn off the M-3000 MK II and replace both the fuse (0.5A, 250V, 20mm glass type) for that
tube and the KT150. To replace a fuse, using a screwdriver, simply turn the top of the fuse cap counter clockwise. It
will spring out holding the fuse. Replace the fuse, push the fuse cap down and turn it clockwise; it will lock itself. If
you have any questions about doing this, please contact Your Allnic dealer for assistance.
If the AC mains fuse, located at the IEC input, has failed, it can be replaced with the spare fuse provided in the tray in
the IEC mount. Again, if you have any questions about doing this, please contact Your Allnic dealer for assistance.
Of course, you will have to adjust the bias back into the area between the two parallel lines of the meter for a tube
when it is replaced. When replacing a KT150, first turn the bias screw counter-clockwise slightly to reduce current,
