Speaker Hum through Krell 400xi/Yamaha RX-V2700


I thought I could figure this out on my own but I guess I was wrong. I have a large number of components which I shall list...

Krell Integrated Amp
Yamaha Receiver
DVD Player
HD Digital Box
Toshiba LCD

I have the Krell connected to the Yamaha RX-V2700 via the THR pass through option with L/R Pre-out on the Yamaha feeding the assigned slots on the Krell. All audio related power cables are connected to a Blue Circle conditioner. The television and DVD player are connected to another power bar (cheap Acoustic Research) The Television is connected to the Yamaha via a single HDMI connection. All other video equipment is connected to the Yamaha directly.

Whenever I switch to the THR input on the Krell to use the Yamaha for movies or television there is a faint buzzing sound from the speakers. I thought I could fix this problem by purchasing a ground level isolating transformer which basically separates the ground (The Krell has grounded plug, the Yamaha doesn't) but it didn't totally cancel out the noise. When no source is playing and the Yamaha and Krell are on I can hear a faint buzz which sometimes sounds as if its fading in and out. On two channel playback (S1 input on the Krell) the speakers are dead quiet; as soon as I switch back to S2 (THR by-pass input) that faint noise comes back which gets louder for the slightest second and fades back to its normal constant hum.


Has anybody experienced this before?

How did you overcome it?
This may well be from the video input. Sometimes cable or sat are not grounded well. Supposedly, there are things you put inline in the cable to cut this, but I never tried one. I did try a transformer like you and that helped, but not enough.

Personally, I gave up and I'm going with separate systems. I am planning to buy the same receiver, BTW. I plan to use the Gallo balls so that I don't have competing speakers in the room (at least only little ones).
nm...stupid me...I had plastic on the two ground leads...it was so small i couldn't see it. I have since removed it and the buzz is gone.
Hi Jerry,

If you haven't bought the RX-V2700 yet its better to wait until September for the RX-V3800...it will support HDMI 1.3 scale analog signals to 1080p with ABT scalers and support DD TrueHD, DTS MA decoding.
You will get better sound if you can use the Krell to feed the Yamaha through the tape loop? Eliminating any Yamaha electronics from the Krell is a huge plus!

I don't think the Yamaha can process digital sound through the tape loop; to be honest I don't have the slightest idea why i'd ever wanna use a tape loop.