Quantum QT600 User Manual
Page 10
6. Standard setup /
Cable connections
7. Troubleshooting
The amp won’t power up when switched on.
• Check the mains cable to see if it is connected properly.
• Check the mains fuse. If it is defective, replace it with another
fuse with identical ratings. If the defect recurs, consult your local
authorised Quantum™ dealer.
The amp is correctly cabled, but no sound is audible.
• Check to see if the MUTE control is activated.
• Check the setting of the GAIN and MASTER controls.
• Check the effects circuit. An inactive or incorrectly cabled effects
device can interrupt the signal.
• Check the headphones output. If headphones are plugged in,
the speaker output is muted.
The DI OUT causes humming noises when in use.
• The earthing of the connected equipment is causing a ground
loop. Never sever the equipment’s safety ground! Instead, set
the GROUND switch to LIFT. If this fails to resolve the problem,
try plugging both devices into the same power distributor.
• An electrical or magnetic field is generating interference.
Use a better quality cord or try to skilfully reposition the cables
to minimise interference.
Feedback arises when DI OUT is in use.
• If the PA’s sound pressure is extreme enough, it can excite the
amp’s speaker and cause feedback when DI OUT is in use.
Since the speaker’s response influences the amp, it could be
routing the interference signal to the DI OUT. Solution:
Try repositioning the amp or using the LINE OUT instead.
When connecting a mixing console to the DI OUT jack the signal
sounds totally distorted over the PA.
• The mixing console’s input is not set to line level. Adjust the level
accordingly at the mixing console. If this is not possible, either
patch the signal to an unbalanced (line) input at the mixing
console or use a connecting cable equipped with an integrated
balanced voltage divider (available from quality music stores
or PA service companies).
The amp’s output level is too low.
• A device connected to the effects loop is reducing the signal level.
Adjust the signal level using the effects device’s input/output
control.
The amp doesn’t sound the way it usually does.
• Check the impedance matching. Mismatching has a negative
effect on the tone quality of the Dynavalve amp.
10
Quantum
TM
QT 600 Manual
5.6 Footswitch
Connect the optional two-way footswitch (Hughes & Kettner
®
FS-2)
to this jack for switching the FX LOOP and PUNCH.
5.7 Speaker Out
Connect speakers to the Speakon jack. Please make sure to wire
the cable correctly (1+=+, 1-=-) and to match the impedance of the
QT600 to the connected speaker
(Chapter 4.2 IMPEDANCE SELECTOR).
Speaker Out
treble
High Mid
Low mid
bass
gain
tuner
out
input
PUNCH
5
0
10
5
0
10
5
0
10
active
passive
TUBE GROWL
master
headphone
on
off
0
-5
+5
0
-5
+5
0
-5
+5
0
-5
+5
mute
bass shape
mid boost
hf-character
6 0 0 - W A T T - B A S S a m p l i f i e r
fOOTswitch
FX-loop / PUNCH
DYNAVALVE
POWERAMP
TECHNOLOGY