HELP!! New AV Amp Pre-out HUM!!

[admin_exported]

Hello,

I've just purchased a Yamaha 1065 with a 5.1 speaker package (Jamo) to integrate with my Naim 5i Amp & CD player to form a 7.1 surround set up (using PS3 as the source).

As soon as I turn on the unity gain feature of the Naim I get a really loud hum coming through the speakers.

Any idea how to stop the loud humming? I've moved the AMP's away from each other in case of inteference; my mains cables/interconnects and speaker cables are all seperated. The Hum only starts when I engage the unity gain......

Please help! I want to watch Hurt Locker with surround sound!!

Thanks in advance

 

[ear]

have another amp you can try?

 

[roger06]

Did you resolve this? As I have exactly the same issue, with exactly the same two amps...

 

[Anonymous]

Could be a ground loop issue. Is the hum, quite deep, say 50Hz, i.e. UK mains freqency?

Are both amps plugged into the same wall socket/mains strips? Is any other kits plugged into either amp, plugged into another mains plug else where? In either case, try plugging all into the same wall socket, via just a couple of mains strips.

Could also be a loop from the aerial sockets, connected to TV/tuners, which are in turn connected to amps. Try unplugging the aerial/cabletv leads from wall - does the hum disappear?

Failing that, you need to unplug everything from everything, and go through each item in turn, testing which causes the hum. Start with just the Naim and speakers connected alone. Then plug AV amp into unity gain, with nowt going into the AV amp. Any hum? If not, one, by one, plug each item you have in. Be wary about stuff plugged into telly, as there can be all sort so of loops with cable boxes, hdmi leads, computers all plugged into this and the amps.

There are few solutions:

Ground loop isolators - cheap audio RCA ones all sound crap - avoid.

Use opitical interconnects where you can.

If its aerial related, try making an aerial patch lead with the outer braid disconnected from one plug; thus only centre wire is connected.

Get sparky in to check mains and earthing.

Get different kit, which is double isolated and has no need of earth connection.

When you read up on groud loop, you will read some people who disconnect the earth pin from kit. Don't ever do this.

SORRY, IN CASE YOU DIDN"T HEAR, DON'T EVER DISCONNECT THE EARTH PIN FROM YOUR KIT. IF THERE'S EVER A FAULT, YOU WILL LIKELY DIE.