E N G L I S H
Thank you for choosing the ATR4502 from KOCH. You now own a "state-of-the-art" guitar power amplifier of the highest quality. The ATR4502 features the unique and totally new
KOCH ATR
Technology (Authentic Tube Response) that makes the amp sound completely like a vintage all-tube amplifier, but with lesser weight and higher reliability. The ATR4502
has been designed and built by people who - from their own experience as musicians - take guitar sound and quality very seriously. That is why this product was designed and built with
the utmost care in order to meet all professional standards. Our goal was not only to design an amp which sounds fantastic and is easy to operate, but also to build it in such a way that it
will serve you loyally for many years to come. Please take your time to read this manual carefully before you switch on the ATR4502.
Thanks and lots of succes with your new ATR4502 !
CAUTION:
* BEFORE PUTTING INTO OPERATION READ
THESE OPERATING INSTRUCTIONS
CAREFULLY.
* NO USER SERVICEABLE PARTS INSIDE.
* REFER SERVICING TO QUALIFIED SERVICE
PERSONNEL ONLY.
WARNING:
* DO NOT BLOCK THE VENTILATION OPENINGS ON THE
FRONT & BACK PANELS.
* TO REDUCE THE RISKS OF ELECTRICAL SHOCK, DO
NOT REMOVE THE COVER.
* TO REDUCE THE RISK OF FIRE OR SHOCK HAZARD, DO
NOT EXPOSE AMPLIFIER TO RAIN OR MOISTURE.
* THIS APPARATUS MUST BE EARTHED.
FRONT PANEL FUNCTIONS
[1] VOLUME:
Controls the volume levels of both channels in MONO mode, or the volume
of channel A in STEREO mode.
[2] VOLUME:
Controls the volume of channel B in STEREO mode.
[3 & 4] VOICING SWITCHES:
DEPTH -
With this switch a filter can be activated that boosts the lowest frequencies. The
effect is subtle but therefore always instantly useable without having to re-adjust the tone
controls.
PRESENCE -
With this switch a filter can be activated that boosts the upper mid
frequencies.
[5 & 6] THERMAL:
These LEDs indicate that the amp has been shut down because of
overheating.
PLEASE CHECK IF THE FANS ARE FUNCTIONING AND IF THE FAN OPENINGS ARE
CLEAN AND FREE.
After cooling down the amp will automatically switch on.
[7] POWER:
Turns AC power On (red LED on) and Off (red LED off). When the switch is
Off the amplifier is completely shut down.
Note: After switching the amp on please allow the tubes to heat up (5-10 seconds).
BACK PANEL FUNCTIONS
[1]
A.C. POWER:
INPUT: Power cord input. The ATR4502 is equipped with a worldwide power supply.
Inside the amp a mains selector switch can be set on one of three voltages, 100, 115 or
230. Either of these voltages will work worldwide with minor power differences. The amp
will work on either 50 or 60 hertz. After resetting the internal mains selector switch
make
sure fuses are replaced with printed ratings on rear of amp.
FUSE: Both fuse and spare fuse are located on the sled of the fuseholder. Fuse sled can
be removed with a screwdriver. If the fuse should fail,
it must be replaced with the same
type and value in order to avoid damage to the amp and to prevent voiding the
warranty.
If the amp repeatedly blows fuses the amp should be taken to a qualified service center
for repair.
WARNING: Only a qualified technician should attempt an input voltage change.
Personel injury or equipment damage may occur if done incorrectly.
WARNING: The fuse should be replaced or the voltage should be reset only when
the power cord has been disconnected from its power source.