Emotiva Ultra UPA-7, Руководство по эксплуатации

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• Make sure the amplifier has good ventilation and is not overheating. Allow good airflow
underneath wherever possible. If the amplifier is in a closed rack, open up the rear panel or use a
quiet fan for improved ventilation.
Poor Bass Performance From Full Range Speakers connected to the UPA-7
• Make sure that your preamp does not have the bass (tone control) level turned down.
• Many surround preamplifiers have controls, which can direct all the bass to subwoofers, or let
your main speakers play the full range. Make sure that the preamplifier has been correctly set. If
you are not using a subwoofer, set the speaker options to “Large” where possible.
• Check that the speaker wires have been connected correctly: Make sure that the positive of each
speaker connects to a positive output of the amplifier, and the negative of each speaker connects
to the negative output. If one speaker is wired incorrectly, then it will be “out of phase” with the
others, resulting in poor bass performance. DOUBLE CHECK ALL THE SPEAKER
CONNECTIONS!!
Turn-on and turn-off thumps
• Plug the amplifier into an un-switched AC outlet, and use the 3.5mm Trigger Input connection
with a trigger between 5-12VDC from the source unit or preamplifier (such as the Emotiva UMC-1
Preamplifier/Processor). This should allow the amplifier to turn on and off silently.
• If your powered subwoofer is the cause of the “thump” sound (not the other speakers connected
to the UPA-7), plug it into a different 115VAC outlet than the UPA-7 amplifier so there is no power
surge conflict.
• Install a line-conditioning device.
“Hum” Noises in the Speakers
• This problem is more than likely caused by a “ground loop” in your system, rather than a fault in
the UPA-7. 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 amplifier, before
disconnecting or connecting any cables during troubleshooting.
• Remember to turn off all components in your system, including the amplifier before disconnecting
or connecting any cables during troubleshooting.
• Try to have all of your equipment on the same electrical outlet or circuit. Group all the low power
components (preamp, CD player, DVD etc.) on a single outlet or power strip. This is provided
that the overall current draw from your equipment does not exceed the rating of the outlet or
breaker.
• Disconnect all cables, which come from outside the room, and check if the hum goes away. This
includes such connections 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
preamplifier or the TV, or any other component. If the hum is caused by the cable TV line, then
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