Can I lift the ground on a Parasound HCA855

Discussion in 'AV Receivers' started by chris_steltz, Feb 28, 2005.

  1. chris_steltz

    chris_steltz Agent

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    Im getting a bad ground loop hum from my parasound HCA-855 does anyone know if these are built to have the ground lifted with one of those cheater plugs? Thanks
     
  2. Steven Simon

    Steven Simon Producer

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    Alot of people say cheater plugs are bad, but I have used them for years without problems... Parasound amps included....
     
  3. John S

    John S Producer

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    Man, I say whatever it takes to get rid of the grounding / hum issue myself. I have lifted more than a ground or two to solve it that's for sure.
     
  4. Steven Simon

    Steven Simon Producer

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    Agreed.... Just don't throw any buckets of water on the amp, and you will be fine... LOL [​IMG]
     
  5. Kevin. W

    Kevin. W Screenwriter

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    what are you using as a pre/pro? Do you use coax or optical for digital sound hookup? Have you disconnected you TV/Sat cable from the tv to see if its solved? Do you have a cable/sat box hooked to your pre/pro via coax for audio? Switch to optical.

    Kevin
     
  6. chris_steltz

    chris_steltz Agent

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    WHen my directv is hooked directly to the TV i get no hum, when i hook it up and turn on the parasound amp i get a hum. as soon as the amp is off nothing. All of ym equipment is 2 pronged where my Parasound is 3.
     
  7. Kevin. W

    Kevin. W Screenwriter

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    Are your DVD and direct TV hooked up via coax or optical to you pre/pro/receiver? Try connecting all via optical. If you have a sub see if unplugging the sub coax cable helps. If you have a surge protector try running your direct tv coax cable into the surge protector then to the tv. This may ground it. Or if your pre/pro/receiver has a FM tuner hookup that accepts tv cable run a piece from it to your surge protector. And before you try any of the above try running a piece of wire from your amp to pre/pro/receiver to see if you can ground them together. Use a screw on the casing of the units to attach the wires too.

    Kevin
     
  8. chris_steltz

    chris_steltz Agent

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    SO if I use optical for the audio what do i use for the video. No matter what I use i get hum.
     
  9. Kevin. W

    Kevin. W Screenwriter

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    I never had a problem with the video being hooked up it was just the digital coax. When I replace them with optical, the hum disappeared. If you still get the hum even after replacing with opticals try:

    1. Removing Sub coax cable hooked to receiver/prepro
    2. Try grounding the amp to receiver/prepro buy connecting a piece of wire between the two. Use screws on the casing.
    3. If you have a surge protector with coax hookups run some cable from your sat to the surge then back to your tv. Or if your receiver/prepro has a FM tunner hookup on back that accepts TV cable run a piece from it to the surge protector.

    Hopefully one of these solutions will ground your setup. For me it was running the cable from my receiver to the surge protector.

    Kevin
     
  10. Randy C Sr

    Randy C Sr Stunt Coordinator

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    Try one of these. Model VRD-1FF. I just ordered one. Several people on the sound and vision forum have resolved that same issue with it. I ran my Satelite and Cable coaxals through my Power Conditioners which reduced the hum significantly. The problem I have left is the noise shows up in my video as a faint rolling scanline/pixel. It too was resolved for someone on the other forum after using the Model VRD-1FF. You can find it at http://www.jensen-transformers.com/iso_vid.html
    It's an in line transformer.

    I'll let you know how it works out for me as well.
     
  11. Chu Gai

    Chu Gai Lead Actor

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    You'll find less expensive versions from Calrad that also do the trick with the incoming cable. Do a search and you'll find some posts by myself and others with a part #.
     
  12. Jason GT

    Jason GT Second Unit

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  13. Chu Gai

    Chu Gai Lead Actor

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    That should do the trick. A nice little page on ground loops can be found here.
     
  14. SteveScammell

    SteveScammell Auditioning

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    I also have a ground loop hum caused by my cable and I recently bought one of the Dayton video isolation transformers from Parts Express to solve the problem. While it did solove the hum problem, it doesn't pass through the entire digital cable signal without degrading it somewhat. A few of the digital cable channels are unwatachable, and it loses the signal momentarily quite often with some of the HD channels (on a Motorola 6412 DVR). I noticed after looking at the specs the Dayton transformer operates in the 100MHZ to 1000MHZ range, while the Jensen VRD-1FF operates in the 2MHZ to 1300MHZ. I just ordered the Jensen VRD-1FF and I'm hoping that it will solve the hum problem with no side effects. Unfortunately it's 5x the cost of the Dayton transformer. I will post again once I have received it.
     

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