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“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 BPA-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 BPA-1, before disconnecting or connecting any cables.
• 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 equip-
ment 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 connec-
tions 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 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 all connections from the preamplifier to your TV, VCR or DVD.
• As a test, disconnect any other component which has a grounded power cord. 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 preamplifier, until you iden-
tify the problem.
• Try moving the speaker cables away from any power cords. Try just one speaker, connecting it to each amplifier channel
and see if one channel is bad.
• Check that the interconnect cables to the amplifier 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.
Ground loop isolators for audio lines and video devices are available from your Emotiva Dealer. Although this is not
always an ideal solution, the grounding differences between certain home entertainment components sometimes require
ground loop isolators. This is the exception rather than the rule.
Other Probable Causes of 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, or halogen lamps or light-dimming Triac devices.
• Try connecting your system to another AC socket on a separate line.
• If the hum is heard from within the BPA-1 and not through the speakers, this may also be caused by interference on the
AC or DC lines. The power transformers may turn this interference into an audible noise. Internal hum can be made
worse by a shelf or cabinet resonating, so try moving the BPA-1 to another shelf.
• Try moving your components further away from the TV, especially if you ever notice the screen has changed color in the
area closest to the component.
If you have very high efficiency speakers, these may tend to reveal noises which other speakers do not.
Problems with the whole A/V System
If you are having more complex problems in your overall home entertainment system (not just with the BPA-1 amplifier),
please contact your Emotiva Dealer or AV123 (Exclusive US Distributor) for professional installation assistance. These
professionals have years of experience with a wide range of home entertainment and lifestyle products and can offer you
assistance in troubleshooting and rectifying problems.
AV123 (Contact Information)
Toll Free -
(877) 543-7500 (menu option 2)
Website -
www.av123.com (click on “support”)
e-mail -
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