Emotiva LPA-1 manual Turn-on and turn-off thumps, Hum Noises in the Speakers

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Check that the speaker wires have been connected correctly: Make sure that the positive of each speaker connects to a positive output of the amplifi er, and the negative of each speaker connects to a negative output. If one speaker is wired incorrectly, than 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 amplifi er into an un-switched AC outlet, and use the 3.5mm Trigger Input connection with a trigger between 3-12VDC from the source unit or preamplifier (such as the Emotiva LMC-1 Preamplifi er/Processor). This should allow the amplifi er to turn on and off silently.

If your powered subwoofer is the cause of the “thump” sound (not the other speakers connected to LPA-1), plug it into a different 110VAC outlet than the LPA-1 amplifi er so there is no power surge confl ict.

Install a line conditioning device. Contact your Emotiva Dealer or AV123 for details.

“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 LPA-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 LPA-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 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 preamplifi er 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 your Emotiva Dealer (unless purchased through AV123) for assistance.

Disconnect all connections from the preamplifi 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 preamplifi er, until you identify the problem.

Try moving the speaker cables away from any power cords. Try just one speaker, connecting it to each amplifi er channel and see if one channel is bad.

Check that the interconnect cables to the amplifi 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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Contents USER’S Guide Table of Contents LPA-1 Technical Specifications Limited Warranty Safety Precautions AV123 NEC National Electrical Code Standards Antenna Grounding Outside the HouseThank You for your LPA-1 Purchase Inventory Unpacking the LPA-1Recording the Serial Number Emotiva LPA-1 Seven Channel Amplifier Front Panel LayoutRear Panel Layout Channels 6 and 7 BridgedAC Power Considerations Installation and ConnectionsPhysical Placement Connection Tips for Superior Sound Input Connection ConsiderationsOutput Connection Considerations Bridging Channels 6Connecting a 7.1 Preamp/Processor Connection DiagramsConnection using a 7 channel preout to LPA-1 Connecting a 5.1 Preamp/Processor Connecting a 5.1 and Second Zone System Connection 5 main channels plus a second 2 channel zoneConnecting Multiple Zones Connection of up to 3 distinct 2 channel zonesConnecting an Expanded Second Zone System 12V Trigger Connections Series Series and Parallel Speaker ConnectionsParallel Technical Note about Multiple Speaker Connections Troubleshooting Guide No Sound from one or more speakers connected to the LPA-1Turn-on and turn-off thumps Hum Noises in the SpeakersOther Probable Causes of Noise Problems with the whole A/V SystemOne or more RED lights on the Front Panel are Blinking LPA-1 Technical Specifications AV123 Contact Information Limited WarrantyService Assistance for the LPA-1 Emotiva DisclosureAV123