C H A P T E R 4
Care and Maintenance of your VTL
amplifier
Break In Period
Your VTL amplifier is designed to give you the continued optimum performance over an extremely long time
period. Initially the tubes and circuits will require a burn-in period to reach maximum performance. During the
first 100 hours of usage the amplifier will undergo several 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.
Tube Life
Your VTL amplifier has been designed to ensure long tube life. Total tube life lasts on the average about 3000
hours (3 to 5 years under normal use.) Your amplifier is designed with a logic controlled automatic tube biasing
and fault sensing system and two manual diagnostic mechanisms, i.e. TUBE TEST and TUBE BIAS, to detect
weak and defective tubes. Please follow the procedures written in this manual to determine when the tubes in
your amplifier should be replaced.
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. The TUBE TIME diagnostic function is designed to inform
you of the cumulative hours your tubes have been in use since the last replacement. When the total Tube Time
reaches 3000, the TUBE GREEN LED bar will light up, and the
Display Window
will show the number “3000.”
This serves as a reminder that you should change your entire set of tubes and after the change, reset your TUBE
TIME counter back to 0.
To reset the TUBE TIME counter, hold down TUBE TIME + TEMP/RESET button simultaneously for 15 seconds,
until the Display Window shows (--) to indicate that the counter is cleared to 0.
The tubes used in your S-400 Reference Amplifier are specially matched and tested for this amplifier. Please
contact your VTL dealer or VTL factory service department to order the matched tubes for your replacement.
Warning:
Tubes can be variable and some types will not yield the best performance or reliability in this
amplifier. Please contact your VTL dealer or the VTL factory to purchase matching tubes for your amplifier.
WARNING: use only tube types and tube brands that are recommended by VTL.
VTL specified replacement tubes are available from your authorized VTL dealer or
the VTL factory service department. Any damage incurred to units which use non-
VTL approved tubes will not be covered under the warranty.
S-400 Amplifier Owner’s Manual
VTL
47
