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7. TUBES
7.1. Removing the grille
See chapter 3.2.
7.2. Tube layout
Output tubes: V1 - V4:
6550 as standard
V1 + V2
left channel
V3 + V4
right channel
Driver tubes:
V5
ECC83 (12AX7)
V6
6922 (ECC88, E88CC)
The pentode output stage topology of the V 40 SE makes it possible to use of a variety of output
tubes. Because the specification limits of the tubes are never exceeded in pentode mode, weaker
output tubes may also be considered. This is facilitated by the option of setting the BIAS current to
two different values: low and high.
Output tubes can be divided into two broad classes – classic pentode output tubes for medium power
amplifiers and modern, high performance pentodes for power amplifiers up to 80 W output.
Low BIAS output tubes include:
6L6, EL34, KT77
High BIAS output tubes include:
6550, KT88,
Note:
Some tubes will fit into the sockets but will still not work with the V 40 SE – the EL509/519, for
example.
7.3. Compatibility power tubes
Model
6L6
EL34
6550
KT88
KT120
KT150
KT170
Serial tube
set
V 40 SE
●
●
●
●
-
-
-
6550JJ
● can be used
-
must not be used
V 1
V 2
V 3
V 4
Power
Protection
Soft Start
Front Ch.
0
10
Disc
Tuner
Aux 1
Aux 2
V 5
V 6