Power Fault -- Mute LED blinking fast red, no deck LED lit
A loss of high voltage at any time during power up or operation will cause a condition where the Power and Mode
LEDs are both off and the Mute LED is blinking fast red with no corresponding tube fault identified by the deck
LEDs next to the output tubes.
If this condition occurs, power off the amplifier with the rocker switch and remove the power cord. Check with a
multimeter that both Plate and Screen fuses are good. If either one of the fuses are open, replace the fuse with the same
value as indicated in the Data Specification section of this manual, and re-power, after allowing 5 minutes to drain the
power supplies.
If both fuses are good, then refer servicing of your amplifier to your authorized VTL dealer or service
technician.
The internal fuse could be blown and the amplifier must be returned to the VTL dealer for
servicing.
Replacing tubes
Turn off the rear rocker switch and remove the power cable before removing any covers
from the amplifier.
Follow the steps below to remove the tube covers on the cage of the amplifier and depending on which tube(s) you are
going to replace, you may only need to remove either the left or the right cover where the tube is located.
MB-450 Series III Signature Monoblock Owner’s Manual
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