Operator`s manual

-> You may be looking at a faulty tube or another defect. In this case,
be sure to take the preamp to an authorized, professional service center.
-> Is there a connection (for example, via a shielded circuit) between the
amp and another device that is grounded via a power plug of its own?
Two or more circuits sharing a common electrical ground line can cause
audible hum. If low-frequency noise is emanating from your rig,
be sure to consult a specialist.
-> The amp and mains grounds are not connected properly or are altogether
disconnected. Have an experienced specialist check this.
-> Cords connected to the input or effect loops may not be shielded properly.
Replace them to check if this is indeed the case.
-> The amp or speaker cords may be picking up interference from powerful
magnetic fields (for example, of nearby power transformers or electrical motors).
Reposition the amp and connector cables.
-> The amp or speaker cords may be picking up radio signals, for example,
from activated mobile telephones or powerful local transmitting stations nearby.
Switch off mobile phones while troubleshooting noise problems.
-> The given power tube is defective and must be replaced if the electronic circuit
breaker continues to trip after several attempts to reset the Tube Monitoring
System by flipping the Standby switch off and back on again.
-> The amp has been overloaded, perhaps by excessive volume levels,
mains over-voltage, or the wrong output impedance (the impedance setting
does not match the connected speaker's impedance).
To protect your combo amp from damage due to overheating, please ensure the
cooling fans remain in operation at all times, especially during lengthy gigs or other
occasions when your amp operates at high temperatures. For studio recording or
other applications that demand silent operation, you may switch off the two fans
for up to two hours, depending on the ambient temperature. You'll find the fan
switch on the back of the amp below the tube protection grille on the side as the
Mains socket (32).
* The speaker is emitting humming noises:
* The electronic power amp protection circuit has tripped:
Important note on the combo version's cooling fans:
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