• Be sure to operate and handle this amp as it was designed for. To this end, please heed the instruc-
tions in the operator‘s manual.
• You‘ll find an additional pamphlet accompanying this owner‘s manual entitled „Instruction for the
prevention of fire, electric shock or injury of persons“. Be sure to read it before you plug the preamp
in and switch it on!
In combination with inherent microphonics of tubes, at certain settings this can elicit powerful feedback
from the speakers – even without a guitar being connected! This occurs primarily when Crunch and Lead
channels (that is, all channels whose preamp is easily over-driven) are activated and the following settings
are dialed in: Gain and/or Lead Gain knob past the 12 o‘clock position; Treble knob past the 12 o‘clock
position; Crunch/Lead Volume knob past the 12 o‘clock position; Presence knob past the 12 o‘clock position.
Avoid setting the aforementioned knobs to extreme positions (that is, combinations in which several of
these knobs are set past the 12 o‘clock position).
This type of configuration can cause considerable feedback that could well damage your hearing and de-
stroy speakers. If you set the Volume or Master knobs to higher volume levels, always make sure to back
off amplification levels to prevent feedback by turning the Lead channel Gain knobs down. The same applies
to these channels´ Treble and Presence knob settings. Before you power the amp up, take a moment to
check out the control panel and make sure that these knobs are not set to any configuration similar to the
one described above! A few words on background noise in tube amplifiers: You may hear slight background
noise right after you power a tube amp up or even while you are operating. It manifests as intermittent
hissing or sizzling, crackling, or popping noises. Caused by tubes, this type of noise may even occur with
brand new tubes. This noise is particularly noticeable in high-gain Lead channels; reason being that these
channels´ gain stages are particularly powerful, amplifying noise along with these useful signal. It is not
necessary to swap tubes if you encounter this kind of noise every now and then, though you may consider
replacing tubes if it becomes a constant companion.
