Note:
if you are using effects pedals with your Komet
, you may want to experiment with the
two different Touch Response
settings to see which one works best with your particular pedal
of choice.
Please note:
when you flip the Touch Response
switch with the standby switch in
the
“ PLAY ”
position, you will hear a slight “
thump
“ coming from the speakers. This is
normal and not indicative of a problem. Engage the
“ STAND BY “
switch before changing the
Touch Response
switch setting if you would prefer not to hear the thump sound.
Note:
be aware that the tone controls on all Komet 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.
BIASING THE KOMET
60 AMPLIFIER
You will find the
Bias Probe Test Points
on the Back panel of the amplifier. They are labeled
V1
(
red
),
Ground
(
black
), and
V2
(
red
). These jacks will accept a standard digital multi-
meter’s red and black probe tips.
V1
is for measuring the bias current draw of the left power
tube,
V2
is for measuring the right power tube. Remove the back panel.
( see instructions on last
page )
On top of the amplifier’s chassis, close to the power tubes, you will find the
bias
adjustment control dial.
This silver colored, hand turned device controls a
10-turn
, precision
potentiometer. You will notice that there is a counter ring on the bottom of the bias dial. This
ring automatically turns one digit for every
360 degree rotation
of the dial. Please be cautious
of the hot power tubes nearby when operating this control.
Note:
the bias control has a small
brake lever
to lock the dial.
This is to prevent the dial from
accidentally being turned and changing your bias setting. Remember to gently release the lock
mechanism on the dial when preparing to adjust bias.
Using a standard digital multimeter
,
insert the probes into the corresponding test points, -
red
probe lead into V1,
black
probe lead into the black insert labeled
ground
. There are no
dangerous voltages present and you will not damage anything. Set your multimeter to the
millivolt
(
mV
)
setting.
Note:
do not set your meter to the
mA
setting. Make sure your amp is
plugged into a speaker cabinet and with no instrument plugged into the input of your amp. Turn
on the amp. After a minute - now that the tubes have warmed up, flip the standby switch to the
“ PLAY ” position.
You will notice a numerical mV reading on your meter. This mV number corresponds exactly to
the amount of bias current
( mA )
that is being drawn from either V1 or V2.
Example:
Insert
probe into V1. Let’s say the meter reads for example
25mV = V1
tube draws
25mA
of bias
current. Then measure the other tube
( V2 ).
The reading should be close and no more than
5mV
apart for the power tubes to be considered a
matched
pair. You can also use this Komet
bias
method to match your own EL34s. Just plug in different pairs, measure each side and mark the
ones that are close. Turning the bias control clockwise will
increase
the reading and
vice versa
(
disengage the brake lever first
).
( continued )
Copyright 2000-2012, Riverfront Music, L.L.C. d.b.a. Komet
Amplification. May not be reproduced in any form without express written
consent from Riverfront Music, L.L.C. d.b.a. Komet
Amplification.