I know you have likely already done this, but is it possible that there is a loose connection somewhere in the system? Would another trip around the system re-tightening all connections of every type make any sense?
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You don't by any chance have you audio system touching your video system, do you? Even if your tv is plugged into the same circuit as you audio, you can pick up a ground loop hum. I had a similar problem and it drove me nuts, I tried running dedicated lines, all sorts of power filters, but it wasn't until I put a MIT Iso-LinQ on my incoming cable line that the problem disappeared.
You could also lift the ground on one piece of equipment at a time until you find the offending component.
as john stated it is a video problem of some kind.first thing to do is check the cable coming into your house.9 out of ten times thats what it is. go to radio shack and buy yourself a ground filter its only 2 bucks.believe me after installing my very expensive system,which hummmed like crazy it was embarrasing to find out that a 2 dollar filter from radio shack cured it.check the cable and vcr and t.v.!!!
good luck harry
Hi and thanks for the replies.
The source of the noise is from the inverter. What I am looking for is someone who has had success with eliminating it with a line filter. Trace states this is normal ie live with it. We can even hear it in the phone line yet I am told it is not RFI. When charging with generator noise is gone( not on inverter power only generator with batteries charging).
All grounds are to Earth Gounding rods. Wire is tight and secure.I am not on cable( nearest cable or power is 10 miles away). The video,computers etc are isolated and switched out of system when not in use. Thier are no motors or compressors on line( no ac/heat refridge is propane).
While this noise is livable as to my original complaint never a black floor to my system.
Tubes do not react the same as SS but noise is still present.
Does the Radio Shack gound filter work on AC or is it for cable only. I do not recieve TV signal wear I am located and use an outdoor 200 mile range antenna for FM. It is grounded to Earth on a separate rod from the house as a precaution from lightning strikes.
I look forward to hearing more ideas.
"It is grounded to Earth on a seperate rod from the house as a precaution from lighting strike"
If your ground rods are not tied together, you may have created a ground loop. The two different grounds will have slightly different potentials and will oscilate between each other causing the hum or ground loop.
You might try disconnecting the FM section of your set up and see if the hum goes away.
On many occassion I have removed the Lead from the antenna during lightning storms "just in case". I can still hear the noise and the lightning charges for that matter with it removed. All the equipment( generator etc , electrical panels boxes ,grounding buses and inverter)grounds are all tied together with bond wire as per installation and NEC requirements.The noise did not show till the inverter was installed and only occurs when it is inverting 48v. to 120v, on generator power it is not present. Buy the way the generator creates more noise from the moter running so it is more intrusive than the inverter interference.
John mentioned the MIT ISO-linQ.What are these?
The funny thing about this is one of the company engineers with Trace worked for Acoustic Research in the old days and I would think that it would be a money maker for Trace to have a solution.
As to noise on the home theater thier is usually alot of background noise in the soundtracks that it is not an issue.
Again Thanks for the replies.
I agree that the source of the noise is the inverter. And it's very hard to get rid of noise that comes from the source of the electrical power itself. I think the most direct way to kill it would be to use a balanced power unit such as Equi-Tech, ExactPower, or Balanced Power Technologies. Basically, they'll divide the single 120V 60~ into two 60V 60~ which are 180 deg. out of phase and
thus null out any line-bourne noise. Read up on it at any of their websites.
Your last post states only happens with SS preamp. Have you considered using a "cheater plug" in the MC preamp to see if the noise lessens? The idea is to reverse polarity going to the MC .
So the Trace people feedback doesn't seem to be OK right? If so I've expected to have the problem all over the place not just with the MC's.
BTW at ca two grand the 4048 better not produce that noise!!!!