Carver pxm250, pxm450, pxm900 Car Amplifier User Manual


 
In Case of Difficulty
If you are having trouble, or suspect a problem with your PXm amplifier, try some simple troubleshooting before contacting
an Authorized Carver Professional Dealer, Authorized Carver Professional Service Center or Carver Professional Technical
Service. Below are listed some general problems and items that should be checked in an attempt to resolve the difficulty.
No Sound, No Power
This is usually an indication of a power supply problem, in either the power line itself or the amplifier's power supply.
Check the following:
1. PXm amplifier power is switched off.
2. Line cord is disconnected.
3. Poor fit between the plug and AC receptacle.
4. Power off at AC receptacle (check with tester or lamp).
5. The amplifier is plugged into a switched outlet. Verify that the outlet is live.
6. PXm amplifier fuse has blown. Check and replace fuse.
Power On, Low Output or No Output
Low or no output problems are usually signal-source, bad cable or partial output short circuit related.
1. The input level controls are set too low.
2. Move the input connection to another amplifier that you know is working to verify that it is not a source problem.
3. Check speaker connections. Be sure that there are no small strands of wire touching similar strands coming from the other
wire in the cable.
4. Make sure the speakers are functioning correctly.
5. If you are using bridged-mono mode, ensure that the Output Configuration Switch is set correctly.
6. Use a voltmeter to determine if the power line voltage is dropping excessively when the amplifier is driven hard.
Playback Is Mixed with Hum
1. Check or replace the connecting cables, between source and amplifier's input.
2. Make sure that each screw terminal connection is tight.
3. Signal cables may have been routed too closely to the AC cables, power transformers, motors or EMI inducing device.
4. Try connecting another source to the power amplifier inputs. If the hum stops, the problem lies with the original source
component.
Distortion
Distortion is usually caused by excessive loss in the input controls (the mixer/equalizer/crossover cannot produce enough
output), overdriving resulting in output clipping, or current limiting caused by excessively low load impedance.
1. Check the setting of the input level controls. If set too low, the preceding piece of equipment may not have sufficient out-
put to overcome the loss.
2. Check the speaker connections and verify that all screw connections are tight and that there are no stray strands of wire to
cause short circuits.
3. Verify that the total load impedance presented to the amplifier is within the limits described in this manual for the mode of
operation selected.
Carver Professional
Service Department
P.O. Box 83189
Portland, Oregon 97283
Phone 503.978.3363 • Fax 503.978.3302
E-mail: carverpro@imagina.com
Web Page: http://www.carverpro.com
Carver Professional reserves the right to improve its products at any time. Therefore, specifications are subject to change without notice.
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O p e rating Ti p s
Using the PXm Amplifiers
Once the amplifier has been installed and wired into the system, you are ready to use it. Here are some tips
to help you get the most from your new PXm amplifier.
Verify that the switches (Output Configuration, Input Sensitivity, High Pass Filter and Clip Limiter) have been set
to the mode or selection that you had intended for your application.
When you power up the system for the first time (out of the carton), it's a good idea to start with all of the amplifier
level controls turned down (counter-clockwise), then advance them slowly, one at a time, so that you can confirm
that each amplifier channel is operating normally.
Be sure that the input level controls are set sufficiently high to allow the preceding device to drive the amplifier to
full output. For most installations, this is wide open (fully clockwise).
Once you have established settings, it is a good idea to mark them down, either on paper, or on pieces of tape or
sticky-dots attached to the amplifier's panel.
In bi-amplified (multi-amp) systems, it is a good idea to start with the low-frequency amplifiers turned down, and
to check each frequency range from highest to lowest to ensure that each loudspeaker component is operating
correctly.
When using the PXm amplifiers, or any high powered amplifier, in multi-way systems as a high frequency amplifier,
it is recommended that a capacitor be used in series with the high frequency drivers. This will ensure that the delicate
high frequency voice coils are protected in case of a catastrophic amplifier failure.
Care and Serv i c e A ss i s ta n c e
C a re : Wipe off the PXm Amplifier's front panel and chassis from time to time, with a soft, dry cloth. If you have
something stubborn to remove, use a mild dish soap or detergent applied sparingly to a soft cloth. Don't use alcohol,
ammonia or other strong solvents.
Service A s s i s t a n c e : We suggest that you read the Limited Warranty completely to fully understand your
warranty/service coverage. Please promptly complete and return the Warranty registration card. Also, be sure to save
the sales receipt in a safe place. It will be necessary for warranty service. If your Carver Professional product should
require service, you may contact the Carver Professional Technical Service Department by calling (503) 978-3363 or by
writing to us at the Factory address found on page 16. We will then direct you to the nearest in our national network of
Authorized Warranty Service Centers, or give you detailed instructions on how to return the product to us for prompt
action. If you should have questions or comments, please write to the Factory address shown on page 19, or contact us
via email at c a r v e r p ro @ i m a g i n a . c o m or at our web site: h t t p : / / w w w. c a r v e r p ro . c o m. Please include the model and
serial number of your Carver Professional product, your complete address and daytime phone number.
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