Troubleshooting - Bose 1800-VI Owner's Manual

Problems/solutions
If you are having trouble or suspect a problem with the Bose
Professional Stereo Power Amplifier, try some simple troubleshooting before contacting an
authorized Bose Service Center.
Problem What to do
No sound, no power • Amplifier power off. Turn on.
• Linecord disconnected.
(Usually an indication of a
• Poor fit between the plug and AC receptacle. Try another receptacle.
power supply problem,
either in the power line
• Power off at AC receptacle. Check with tester or lamp.
itself or the amplifier's
• Blown amplifier fuse. Replace fuse.
power supply.)
• Open thermal breaker in the power transformer. Allow amplifier to
cool and the breaker will reset itself.
Power on, low output • Input level controls set too low. Reset.
or no output • Check to see if problem is at the source. Move the input
(Usually signal-source, connections to another amplifier you know is working.
bad cable or partial
• Be sure that there are no small strands of wire touching similar
output short circuit
related.)
strands coming from the other wire in the cable.
• Make sure the speakers are functioning correctly.
• If you are using bridged-mono mode, make sure the stereo/mono
switch is set correctly.
• Use a voltmeter to determine if the power line voltage is dropping
excessively when the amplifier is driven hard.
Playback mixed • Check or replace the connecting cables.
with hum • Make sure that each screw terminal connection is tight.
• Signal cables may have been routed too closely to AC cables,
power transformers, motors or other EMI inducing device.
• Connect another source to the power amplifier inputs. If the hum
stops, the problem lies with the original source component.
Distortion • Check input level controls. If set too low, the preceding piece of
(Usually caused by
equipment may not have sufficient output to overcome the loss.
excessive loss in the input
• Check speaker connections and verify that all screw connections
controls when the mixer/
equalizer/crossover does
are tight and that there are no stray strands of wire to cause
not produce enough
short circuits.
output. Also caused by
over-driving that results in
• Verify that the total load impedance presented to the amplifier
output clipping, or current
is within the limits described in this manual for the mode of
limiting caused by
excessively low load
operation selected.
impedances.)
Unnatural sound • Check the EQ cards. Verify that the EQ card corresponds to the
model speaker being used and that the EQ card is installed in the
(Some parts of the
frequency band do not
proper channel. Verify that the speakers are connected to the
sound balanced with the
same channel that the corresponding EQ card is installed in.
rest of the band.)
Care • Wipe the front panel and chassis with a soft, dry cloth.
• For stubborn spots, use a mild dish soap or detergent sparingly
applied to a soft cloth.
• Don't use alcohol, ammonia, or other strong solvents.
®
Model 1800-VI or 1600-VI

6.0 Troubleshooting

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