Octave RE 280 MK2, Руководство пользователя

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7. TUBES
7.1. Tube layout
V1
V2 V3
V4
V7 V6 V5
Output tubes: V1 - V4: 6550 or KT 88 fitted as standard
Driver tubes:
V5 - V7 ECC82 (E82CC, 12AU7A, 5814, 6189)
7.2. Tube service life
Thanks to the protection circuits and soft start electronics, the output tubes used in your amplifier
should achieve an average service life of 3 to 5 years. Although this life expectancy figure is typi-
cal, it cannot, of course, be guaranteed absolutely, since it is dependent on the type and the manu-
facturer of the tubes themselves.
The internal protection and soft start circuits cannot prevent tube faults. They are designed to
minimize the stress on the amplifier and to protect it should a fault develop. You can select tubes
by measuring their characteristics, but this does not guarantee that they will last for a long time.
Indeed, it is impossible to predict how long output tubes will last. A well-made tube has a life expec-
tancy of between 3 and 5 years. However, it remains impossible to detect certain weaknesses in
the structure of a fully functional tube.
The protection circuits in the power amplifier will also protect the unit against the damage that a
defective output tube could cause.
 Driver tubes can last for 10 years or longer.
 Because tubes have different service lives, you will never have to renew the entire tube com-
plement at the same time.
 Please note that some tubes need a long time (up to 300 hours) to achieve their optimum sound
quality.