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Troubleshooting 6
®
Troubleshooting
©2004 PS Audio International Inc. All rights reserved.
Owner’s Reference
A-100 Power Amplifi er
If no sound comes out of the A-100 Power Amplifi er there are several areas to check. Either you are
not getting an audio signal into the amplifi er, you are not properly connected to the loudspeakers so
the audio can get out of the amplifi er, or there is no power from the AC socket.
It is obviously important that the A-100 Power Amplifi er receive a high level signal from the preamplifi er,
surround processor or whatever source you are feeding it. One way to determine if this is the case,
would be to fi rst go to your loudspeaker. Place your ear near the tweeter and listen for a very slight
hiss. If you hear one, chances are good the amp is working fi ne, connected properly at the speakers
and you have an input problem. If you suspect an input problem, the fi rst thing to check is the rear
panel switch. The switch on the rear of the A-100 Power Amplifi er is an input selector. With a source
connected to the preamp and the preamp volume turned up, click the rear mounted input selector on
the A-100 Power Amplifi er to both positions and see if this solves the problem.
If not, place the switch to the proper position and replace the interconnects between the preamp and
power amp. At last resort, if you suspect an input problem, try another preamp, or plug the output of
your CD player or DVD player directly into the A-100 Power Amplifi er. Be careful to choose a CD or
DVD with relatively soft music because this will play very loudly.
If you suspect an output problem, use the same technique of placing your ear very close to the
speaker’s tweeter while the A-100 Power Amplifi er is turned on. You should hear a very slight amount
of hiss from the tweeter. If you do not, check the speaker cable/amp connection. Make sure the
amp’s front panel light is on, indicating proper performance.
If there is no sound and you are convinced the A-100 Power Amplifi er has power and its front panel
light is lit, contact your dealer, distributor or PS Audio for further assistance.
If there is an excessive amount of hiss or noise from the loudspeaker, it is probably not from the A-100
Power Amplifi er as this amp has extremely low self noise. Turn the amp off, remove the interconnect
cables from the A-100 Power Amplifi er and then turn the amplifi er back on. Listen once again to see if
the noise has been diminished. If it has, chances are good you either need to replace your preamplifi er
with a quieter one or you may need to experiment with better shielded interconnect cables.
If you experience a hum through the speakers this can be caused by several things. The fi rst is the
source. If there is an excessive amount of buzz or noise from the loudspeaker, it may be caused by a
ground loop, a light dimmer in the home, poor AC power, or any number of causes. The quickest way
to determine where to start your search is to simply turn the amp off, disconnect the cables feeding
its input, and see if the hum goes away when you turn it back on. If it does, it’s most likely a ground
loop or buzz from a dimmer.
The easiest way to fi gure out where ground loop problems lie is by the process of elimination. You
need to determine where the hum or buzz is coming from within your system.
If the hum/buzz goes away when you remove the inputs to the power amp, your next step will be
No sound comes
out of the amp
Check the input
If you suspect an
output problem
If there is a lot
of hiss in your
speaker
Check the rear
input selector fi rst
Try another
source
If you have hum
or buzz
