[dcloomer]

Got one of Brian's new amps for my larger sub and it immediately introduced loud hum into the system.  Per the instructions with the amp, I isolated it to the coax cable coming into the cable box HT sytem.  Purchased the inline filter to go between the cable and the box---->no more hum.  However, also no more HD channels.  
This filter does too good a job.  The folks at Comcast show low level seizure activity when you try to explain the situation.  Their solution:  live with the hum.
Any ideas?  Any way to filter out only hum and not cable content?

[StevenACNJ]

I use this product from Jensen: VRD-1FF Cable TV Ground Loop Isolator

Link:

http://www.jensen-transformers.com/

Scroll down a bit - mid page.

This product eliminated all hum and I get perfect cable reception (including HD channels). Comcast with Motorolla digital box.

I installed it right at the point where cable enters my home.

[dcloomer]

Thanks, Steven.

I think that's the same part that I got.  I'll try it in the spot in the chain that you've placed it.  Don't know why that would make a difference, but there's a long list of things that I don't understand.

Take it easy.

Don

[SWG255]

I bought an audio transformer and inserted it between the audio output of my Tivo and the Aux in of my preamp, and no more hum. It is a "pro" audio transformer that cost about $40, and frankly, with Direct TV audio, I don't notice any sonic degradation using this transformer. It certainly sounds better with the transformer eliminating the hum and buzz than it did with all that noise in the audio. Of course, it has no effect on the video and I didn't have to go outside to install it.

[loki1957]

I had the same problem, break the ground off the power cord or use a 3 way converter, hum all gone.

[dcloomer]

Thanks for the tricks.  Question:  "?3-way converter?"

[Karl_in_Chicago]

Thanks for the tricks.  Question:  "?3-way converter?"

I believe that's referring to a pass-thru plug adapter that accepts a 3-pronged plug but only puts 2 into the outlet (dropping the ground out).

[dcloomer]

Got it.  I'll give these a try.
Thanks.

Don

[ctviggen]

I don't think it's a good idea to break off the ground of a 3-prong plug.  Although it's unlikely that you'll have to use the safety benefits of the ground, if you do have to use it, the ground could save your life.  Personally, I'd look to see where the cable enters the house.  Ground the cable at that point to the house ground.   You could also add another ground rod (hammered into the earth), but the ground rod and house ground should be connected using thick-gauge wire (#6 I believe) according to the National Electrical Code (NEC).  Plus, if you don't ground to the same point, you increase susceptibility to ground loops.  

At my house, grounding the cable to the earth ground (itself grounded to the house ground) solved any hum caused by the cable box.

[loki1957]

It sure is alot easier and quicker to short the ground at the plug with a converter or breaking off the ground. If that works great, doesn't cost anything, if it doesn't work then you can check for other things. As long as your IC is hooked up to a grounded preamp your grounded at the sub amp.

[OTL]

Mondial Magic has been in my system for 13 years or so.  Get the splitter for @ $100 bucks.

http:// http://www.klipsch.com/product/list.aspx?line=1261&type=1273

[dcloomer]

Looks like Steven was right in the first place:  after trying many of these things, what finally ended up solving the problem without removing the digital channels was the filter from http://www.jensen-transformers.com/
The other things either didn't work or worked but filtered out the digital channels and HD.  Turns out, the other (read cheaper) filter that I had purchased could not be used with digital systems. 

Thanks again, Steven.

My recommendations to http://www.jensen-transformers.com/
However, you can buy them cheaper from internet distributors than from the company itself.