Emotiva USP-1 - Manual (Page 19)

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• Check that the amplifier(s) power output is a good match for your speakers. If your speakers are
inefficient, consider using larger power amplifiers.
• Make sure all wiring is correct and there are no shorts. If wires have been run under carpet, under
base boards (or along tack strips) there is a possibility they can easily be shorted by sharp edges
or something that punctures the insulation. Also, if your wiring is in the walls - make sure that
there was not an accidental “staple” puncture from securing wiring to framing studs or wall/floor
joists. This evaluation is easily done with an Ohm meter.
Remotely Connected External Amplifier(s) Do Not Turn Off with USP-1
Check the following:
• Make sure the 1/8” plug is connected between USP-1 trigger output and the amplifier(s) trigger
input(s).
• Make sure the total consumption of the connected devices do not exceed 500mA
• If you have spliced the plug to one or more amplifier turn on inputs, remember the center pin is
positive and the outer shield is negative. This output is 12VDC.
“Hum” Noises
• This problem is more than likely caused by a “ground loop” in your system, rather than a fault in
the USP-1. Follow these steps to isolate the main cause of the hum; there may even be more
than one. Remember to turn off all components in your system (including the USP-1) before
disconnecting or connecting any cables.
Disconnect the following items in order, and check each time if the hum has gone away:
• Disconnect all cables which come from outside the room, such as cable TV, satellite TV, or roof
top antennas. Make sure that they are disconnected where they first enter the room, so they are
making no connection to the USP-1, the TV, or any other component. If the hum is caused by the
cable TV line, you will need a “ground loop isolator.” This is an inexpensive device fitted in-line
with the coaxial cable feed. Contact your cable company or your Emotiva Dealer for assistance.
• Disconnect any component which has a grounded power cord.
• If the hum persists, disconnect all the source components one at a time from the back of the
USP-1 until you identify the problem. (Ground loop isolators are available for audio lines and
video. Ask Emotiva for assistance)
• Try moving the speaker cables away from any power cords. Try just one speaker, connecting it to
different channels and see if an amplifier channel is bad.
• If you are still having a problem, remember that Emotiva’s technical support staff will assist you.
Other Probable Causes of Speaker Noise
•
Speaker noise may also be caused by interference or noise on your AC line. Make sure there are
no large appliances sharing the line, halogen lamps, or light-dimming Triac devices.
• Try connecting your system to another AC socket on a separate line.
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