Emotiva XPA-1, Руководство пользователя

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Poor Bass Performance from Full Range Speakers
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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 ampli fi er 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 preampli fi er. This should allow the ampli fi er to turn on and off silently.
•
If your powered subwoofer is the cause of the “thump” sound (not the other speakers connected to the amplifier),
plug it into a different 115VAC outlet than the ampli fi er so there is no power surge con fl ict.
•
Install a line ‐ conditioning device.
“Hum” Noises in the Speakers
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This problem is more than likely caused by a “ground loop” in your system, rather than a fault in the amplifier.
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 ampli fi er, 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 fi rst
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 you will need a “ground loop isolator.” This is an inexpensive device fi tted in line
with the coaxial cable feed. Contact your Cable Company or Emotiva for assistance.
•
Disconnect all connections from the preampli fi er to your TV, VCR or DVD.
• As a test, disconnect any other component, which has a grounded power cord.
NOTE: Never remove the ground pin from any power cords (if present). This is very dangerous.
If the hum persists, disconnect all the source components one at a time from the back of the preampli fi er, until you identify
the problem.
• Try moving the speaker cables away from any power cords. Try just one speaker, connecting it to each ampli fi er
channel and see if one channel is bad.
Check that the interconnect cables to the ampli fi er do not have any broken connections. The best way to do this is to
substitute a known good connection for the suspect connection. If you reverse the cables and the problem goes away, the
cable may be damaged or broken. This is possible even if you can’t physically see the break as the strain for pulling on audio
cables can sometimes break the wire internally.
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