C H A P T E R 4
Care and Maintenance of your VTL
Amplifier
Break In Period
Your VTL amplifier is a pure tube product designed to give you the continued optimum performance over a long time
period. Even though the amplifier has undergone a burn-in cycle in the VTL factory, the tubes and circuits will require
further usage and burn-in to reach maximum performance. During the first 100 hours of usage the amplifier will undergo
noticeable improvements in sound.
To break in the amplifier you can leave it on with a music source connected to it
and playing with the volume control turned to low level. Do not leave the amplifier on if you are not home.
Power-on Period
We recommend that your amplifier should be set to Mute mode when you are done with your listening session but you
intend to return to your listening session within the same day or in a couple of hours. You can turn off the amplifier using
the Power button if you are done with your listening session for the day and leave the amplifier in standby mode. If you are
not going to use the amplifier for an extended period of time, we recommend that you turn off the amplifier from the rocker
switch located on the back panel of the amplifier.
Tube Types
The VTL MB-450 Series III Signature Monoblock amplifier uses a total eight 6550C tubes for the output stage and one
12AT7 and one 12BH7 tube for the input and driver stages.
Tube Life
Your VTL amplifier has been designed to ensure long tube life.
Total tube life generally lasts on the average about
3000 hours depending on the usage pattern. Your amplifier is designed with a logic controlled automatic tube
biasing and fault sensing system that will inform you when a tube should be changed. Please follow the
procedures written in this manual to determine which tube in your amplifier should be replaced when the
amplifier indicates a tube fault condition.
We recommend a complete replacement of all tubes in your amplifier after 3000 hours of usage, which will
restore the amplifier to a “like new” sound quality.
As the tubes age beyond their peak performance they begin to lose
their ability to provide full power. This usually results in some loss of control in the bass and a general softening of the sound
in the upper frequencies.
Your VTL dealer or VTL factory service department will be happy to assist you with the re-tubing process.
MB-450 Series III Signature Monoblock Owner’s Manual
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