Komet Aero 33, Owner'S Manual, Page: 7 / 22

Note : when using effects pedals with your Komet  amplifier, you may want to experiment with
the two different settings of the Fast / Gradual switch to see which one works best with your
particular pedal
(
s
)
of choice.
Note
: please be aware that the tone controls on all Komet  amplifier models are passive, but
very powerful. If you come across a set of parameters, which does not work well with your
guitar/ speaker combination, simply change the settings, and avoid that particular setup in the
future.
TUBE CHOICES FOR THE AERO

33
PRECAUTION : always allow the power and pre amp tubes to cool down before handling. They
are made of glass and can easily break when mishandled. Wear safety goggles and heat
protective gloves when handling hot tubes.
Never remove or replace the power or pre amp tubes
while an amplifier is on.
The Aero

33
was designed and voiced to utilize current production tubes to their maximum
potential. The current stock power tubes (V4,V5,V6 and V7) are a matched set of Sovtek  EL84 /
6BQ5s. This is a widely available and reliable power tube. The Mullard re-issue EL84/6BQ5 by
Sovtek
 is an excellent replacement upgrade.
We prefer the Sovtek
 12AX7 LPS
for the V1
(
input stage
),
V2 and V3
(
the phase inverter position
)
positions
. The LPS is an excellent sounding 12AX7 and are used in all Komet

amplifier models.
The re-issue Sovtek  Mullard 12AX7 is another excellent 12AX7 option. With this factory stock
tube compliment, the Aero
 33
sounds powerful, complex and detailed. The distortion is balanced
and harmonically rich.
Please note
: you may find that some pre amp tubes, whether newly manufactured, used, or even
n.o.s., may be too
"
microphonic
"
for the first gain stage
(V1)
of a Komet

amplifier. A
microphonic preamp tube is a condition in which a tube will absorb mechanical vibration and
amplify it into the audible range. In this scenario, a tube can
"
feed-back
"
, or give off a loud, high
pitched squealing noise.
Feed-back can occur intermittently, even without an instrument plugged into the input of the
amp. This does not mean that the tube
(
s
)
are completely unusable. One possible solution you can
experiment with is moving the microphonic tube to the
V2
phase inverter socket where
microphonics are not as noticeable. The microphonic
12AX7
may be quieter in the
V2
position as
opposed to the
V1
position.
Please note
: a small amount of
"
hiss
"
is normal for high gain amplifiers. An excessive amount
of hiss, especially when the volume control of the amplifier is all the way down and with no
instrument plugged in the amplifier’s input, usually denotes a bad pre amp tube. Some n.o.s.
audio tube suppliers offer
"
select
"
or hand picked pre amp tubes, which are superior in all aspects
of quality, especially when it comes to being quiet and non-microphonic.
(continued)
Copyright 1999-2017, Komet

Amplification. Group, L.L.C. May not be reproduced in any form without express written consent from Komet

Amplification.