Komet Aero 33 Owner's Manual page 12

Amp is making a Humming
"
This is most likely a bad pre amp tube. Pre amp tubes can develop problems over their life span.
They may be operating flawlessly, and they may also test fine on a tube tester, but for what
appears like for no reason, can suddenly begin to make a "hissing" or a "crackling" sound. They
can begin to feedback or have microphonic or "ringing" symptoms, or develop filament
"humming" - which is a low background hum, often mistaken for a problematic filter cap.
Filament "humming" is much more common with new, modern available pre amp tubes.
Unfortunately, you will most likely have to replace one of more of your pre amp tubes with any
of these problems.
Fluorescent and neon lights, rheostat wall dimmers, and some appliances may cause your amp to
contain a hum or buzz
" " "
a guitar cable can also create a
Over time, the input jack may occasionally make a
instrument cable from the front panel of your amp. This is usually due to a dust / contaminate
build up on the input jack's ground shunt. This would require that the inside of the input jack be
cleaned professionally. We recommend using
Amp sounds spongy
"
A spongy or sputtering
" " "
normal operating conditions, this symptomatic sound can be the result of
i.e. power tubes that have reached their operational lifespan. You may also notice this symptom
when the volume control and saturation control are completely
new power tubes. This is a result of both the power tubes and output transformer reaching
complete saturation and is part of the circuit design. Backing off each control a small degree will
re-align the signal path.
TUBE REPLACEMENT FOR THE AERO
Unscrew
(in small increments)
evenly with two hands. Use the reverse instructions when installing the Aero
panel. You will find the tube placement chart on the back panel of you amp. There are six tube
sockets in total. These sockets are miniature nine pin pre amp tube socket types.
Follow the placement of the four tubes by referring to the tube chart. Make sure the amplifier's
tubes have cooled down sufficiently before handling the amplifier's tubes.
12AX7 pre amp tubes.
Gently install each tube in the correct corresponding tube socket. Please note each tube's pin
configuration must be properly and perfectly aligned with the tube socket for installation. Do not
force a tube into its socket. If correctly aligned, it should easily install into the socket.
Copyright 1999-2017, KometAmplification. Group, L.L.C. May not be reproduced in any form without express written consent from KometAmplification.
, Hissing ,
" " " "
sound. An internally shorted guitar cable or using a speaker cable for
"
buzz sound through your amp.
" "
or sputtering :
" " "
- weak response from your amp can be one of two things. Under
"
the two, back panel insertion screws. Remove the back panel
through are the EL84/6BQ5 power tubes.
V4 V7
Feedback or Crackling
" "
crackle sound when you extract your
" "
G5.
DeoxIT Gold
®
dimed
"
33

- sound:
"
weak power tubes,
" "
out 100%, even with
"
 head back
33
, and are the
V1 V2 V3