The problem may be that your satellite and electrical are grounded in different places. This could be creating a ground loop. Have you tried also grounding the sat to the ground rod? I had a similar problem with my cable a number of years ago. I solved the problem by grounding my cable to my electric meter.
how to eliminate another anoying 'hum' from tubed
I never had a ground loop hum before; but I decided to upgrade my gear from a Meridian 861/hd621 switch and G-98 to a VAC Phi Beta tubed preamp, PS audio perfect wave d/t, and a new Marantz 7005 a/v processor. I am using a Parasound A-51 multi channel for center and rears, Velodyne DD-15 sub; Direct tv dish, and Bryston 28 sst's monos for main.
When I connected this gear; everytime I simply touched the hdmi from sat to either my tv; or processor; I had a loud and bad 'hum'; thought maybe it was problem with sat. I had an electrician come out; installed a grounding rod into earth; and also fixed ground. Still had hum; then I realized when I used AEU balanced cables from VAC in cinema mode to Marantz; it created the hum and ground loop. Called VAC; they suggested I use rca ic's, but keep source selection as balanced to 'fool' the ground problem. I did that; and it eliminated 85% of hum, but not all of it. Hum only occurs when I switch the source on VAC from two channel into Cinema mode; otherwise on two channel music; system is completely quiet with no hum. I have three dedicated 20 amp lines.
Does anyone have any thoughts on how to eliminate remaining hum? I did borrow an Integra 80.2 to see if it was problem with Marantz; the Integra had significantly less hum; it may have different internal grounding or switching; also Marantz did send me out a replacement 7005, both units had same hum issues. Is there just bad synergy between VAC and Marantz, or can this be cured. Thanks for your thougths; I have gone thru many different solutions..but not there yet.
Happy Holidays and Thanks...
When I connected this gear; everytime I simply touched the hdmi from sat to either my tv; or processor; I had a loud and bad 'hum'; thought maybe it was problem with sat. I had an electrician come out; installed a grounding rod into earth; and also fixed ground. Still had hum; then I realized when I used AEU balanced cables from VAC in cinema mode to Marantz; it created the hum and ground loop. Called VAC; they suggested I use rca ic's, but keep source selection as balanced to 'fool' the ground problem. I did that; and it eliminated 85% of hum, but not all of it. Hum only occurs when I switch the source on VAC from two channel into Cinema mode; otherwise on two channel music; system is completely quiet with no hum. I have three dedicated 20 amp lines.
Does anyone have any thoughts on how to eliminate remaining hum? I did borrow an Integra 80.2 to see if it was problem with Marantz; the Integra had significantly less hum; it may have different internal grounding or switching; also Marantz did send me out a replacement 7005, both units had same hum issues. Is there just bad synergy between VAC and Marantz, or can this be cured. Thanks for your thougths; I have gone thru many different solutions..but not there yet.
Happy Holidays and Thanks...
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The problem may be that your satellite and electrical are grounded in different places. This could be creating a ground loop. Have you tried also grounding the sat to the ground rod? I had a similar problem with my cable a number of years ago. I solved the problem by grounding my cable to my electric meter. |
Lostbears: Yes; the ground is isolated to the ground rod; which is located at the opposite side of the house where the main panel is located; over 100 feet away...none of the other sat receiver boxes in house have ground hum; when hooked up to other a/v receivers; only problem is my main rig; and only when the VAC pre amp is switched from 2 channel to cinema mode...which is why I am asking the forum readers for possible solutions...I am stumped...thanks for the thought.. |
tried a Jensen product; but it states on box not designed for satelite feeds; it only works with cable tv boxes for some reason; I placed one in my rig; reduced hum; but it failed to send sat signal to set; screen had ' searching for satelite' error message...don't know why they are not approved or work for Directv sat boxes... please try to keep these ideas coming....I am stumped and am appealing to the force of the 'Gon for a cure of the humming blues... |
OK, here are some ground isolation xformers that say they will work w satellite TV http://www.mcmelectronics.com/product/33-8700&CAWELAID=220406689 and http://www.rackmount-devices.com/main.html?page=015-8700. No relation to seller, YMMV, etc, etc. |
Try buying a line level isolator. I bought one very cheaply at Best Buy by Stinger...usually found in the car audio section. Basically a small transformer with 2 pairs of wires. One pair is female and another 'output' pair that are male. This is a bridge between the IC's between the VAC and Marantz. I had the same problem using various Integrated amplifiers and HT receivers (used as a SSP). You can tape the ground wires. Should completely deaden the noise. |