Troubleshooting - Hughes & Kettner ATTAX 100 Manuel

ATTAX-MANUAL
- When connecting peripheral devices, always pay close
attention to their specifications. Never connect devices with
high output signal levels (e.g. power amps) to your amp's
input.
- Ensure you have the correct AC power rating available
before you plug in the amp. If in doubt, ask the venue's
sound technician or the custodian of the building you are
rehearsing in.
- Refrain from do-it-yourself repairs! Have a qualified servi-
ce technician replace internal fuses.
Tube fatigue is normal after several hundred operating hours
and is manifest in the form of treble loss or increased micro-
phonics.
Use a soft damp cloth to clean the exterior surface of the
ATTAX 100.

6.0 TROUBLESHOOTING

1) The ATTAX will not switch on:
- The amp is not getting any AC power. Check the mains
cable to see if it is connected properly.
- The mains fuse is defective. Replace the fuse with another
identical fuse. If this fuse also trips, consult your Hughes &
Kettner dealer.
- One of the secondary fuses has tripped because the MIDI
Module was installed incorrectly (reverse polarity). Once
the ribbon cable connector has been installed correctly, the
secondary fuse can be replaced. Only experienced service
technicians may conduct this type of repair work.
2) The ATTAX is connected properly, but no sound is
audible.
- One or several GAIN and MASTER controls may be turned
all the way down. Dial in a higher setting.
- The FX-MIX control is turned all the way to WET but you
have not connected a processor to the FX loop. Turn the FX-
MIX knob to DRY.
- A short circuit in the speaker signal chain may have trip-
ped an internal fuse. Make sure none of the connections are
shorted out and have a qualified service technician replace
the fuse (identical specifications are a must).
3) The STAGEBOARD cannot activate the CLEAN/CRUNCH
channels:
- The front panel selector switch is not in the "OFF" positi-
on. Set the appropriate switches to "OFF".
- The STAGEBOARD is not connected to the ATTAX. Plug it
into the appropriate jack.
- The MIDI module was previously active. Briefly press the
MIDI LEARN button to clear the MIDI mode.
4) The sound is thin and muddy when the effects processor
is active.
- The signal processor is causing undesirable phase shifting
that is being added to the original signal in the parallel
loop. Turn the FX-MIX control all the way to the right (WET)
to avoid phase cancellations.
5) When accessed, the RECORDING OUT jack causes
annoying hum.
- An electrical or magnetic field is causing interference. Use
higher-quality cables or re-arrange the cables you are using
to reduce interference to a minimum. If this still doesn't
improve the situation, use a DI box.
- The grounding of the connected devices may be causing a
ground loop. DO NOT SEVER THE GROUND OF THE
CONNECTED DEVICES UNDER ANY CIRCUMSTANCES!
Try plugging all devices into the same socket via an AC
power distributor/power strip. If this doesn't eliminate the
noise, you must ensure the connection is galvanically sepa-
rated by routing the signal through a DI box.
6) You have connected the RECORDING OUT jack to a
mixing console and the signal is totally distorted, even
when you have dialed in a clean sound.
- The RECORDING OUT signal may be overloading the
mixing console's input. Reduce the mixing console's input
sensitivity (GAIN). If this doesn't rectify the problem, patch
the signal to the mixing console's LINE input.
7) You have connected the RECORDING OUT jack to a
mixing console and the signal's volume level is way too
low.
- The amp's output level is limited by an incorrectly adju-
sted FX processor's output level. Turn the FX processor's
level up.
- The mixing console's line input is not sensitive enough.
Turn up the gain. If this is still insufficient, use the micro-
phone input (if necessary, use an adapter cable or DI box).
8) You have connected the RECORDING OUT jack to a
mixing console, but you find it doesn't deliver the sound
you had in mind.
- The RECORDING OUT circuit is dual-purpose. It is also
designed to allow you to feed its signal to an additional
power amp and cabinet. For absolutely top-notch professio-
nal recording purposes, route the signal through a Hughes &
Kettner RED BOX before patching it to a mixing console.
11