Can a speaker-wire short fry an amp?

Discussion in 'AV Receivers' started by Mathhew+M, Jun 23, 2004.

  1. Mathhew+M

    Mathhew+M Auditioning

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    As I said in my other thread, my 3-yr old Pioneer VSX-D711 no longer powers up. I talked to a few shops and it seems like it will cost (at a minimum) almost as much as a new unit, plus I'd have to wait 4-6 weeks. One shop mentioned that a speaker short might have caused an IC to fry. I have a hard time believing that a short in a speaker wire could destroy a reciever, am I naive to think it couldn't happen? Also, I now have an old Sony Pro-Logic only unit substituting until I get a replacement, and all speakers work fine and there appears to be no problems. If it was a speaker wire problem, wouldn't I be noticing it with the old Sony unit too?

    I have fears of buying a new unit only to have it fry the night I install it, as I still don't know why the Pioneer went bad... [​IMG]
     
  2. Mathhew+M

    Mathhew+M Auditioning

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    As I said in my other thread, my 3-yr old Pioneer VSX-D711 no longer powers up. I talked to a few shops and it seems like it will cost (at a minimum) almost as much as a new unit, plus I'd have to wait 4-6 weeks. One shop mentioned that a speaker short might have caused an IC to fry. I have a hard time believing that a short in a speaker wire could destroy a reciever, am I naive to think it couldn't happen? Also, I now have an old Sony Pro-Logic only unit substituting until I get a replacement, and all speakers work fine and there appears to be no problems. If it was a speaker wire problem, wouldn't I be noticing it with the old Sony unit too?

    I have fears of buying a new unit only to have it fry the night I install it, as I still don't know why the Pioneer went bad... [​IMG]
     
  3. Paul S

    Paul S Stunt Coordinator

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    There may not be any reason that you are responsible for that made the Pioneer go bad. Sometimes electronic parts fail.

    If you are worried about a short in your speaker wire, just go over to the Radio Shack and buy an electric tester. They are reasonably priced. You can then very easily test the wire to see if it is shorted. Or for very little money you can go to a Home Depot store and buy some very nice 16 gage stranded wire (very inexpensive) and just use new wire for your speakers.
     
  4. Paul S

    Paul S Stunt Coordinator

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    There may not be any reason that you are responsible for that made the Pioneer go bad. Sometimes electronic parts fail.

    If you are worried about a short in your speaker wire, just go over to the Radio Shack and buy an electric tester. They are reasonably priced. You can then very easily test the wire to see if it is shorted. Or for very little money you can go to a Home Depot store and buy some very nice 16 gage stranded wire (very inexpensive) and just use new wire for your speakers.
     
  5. Greg_R

    Greg_R Screenwriter

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    Yes, a speaker wire can short and fry an amplifier. However, virtually all receivers and amps have protection circuitry to prevent this (the damage, not the short) from occurring.
     
  6. Greg_R

    Greg_R Screenwriter

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    Yes, a speaker wire can short and fry an amplifier. However, virtually all receivers and amps have protection circuitry to prevent this (the damage, not the short) from occurring.
     
  7. Steve Berger

    Steve Berger Supporting Actor

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    Actually the protection circuits are there to protect the speakers from an amplifier short. (shorted outputs can put 60 to 100 volts at 8 - 10 amps accross a speaker winding ; destroying the speaker very quickly) Almost nothing is fast enough to protect the outputs from an instantaneous overload caused by a momentary short (wires briefly touching). At least with high power amps. With speaker wiring , neatness counts. Most output failures are caused by brief , accidental , crossing of the speaker wires. Overload protection works best if a short is present when the amp powers up. If the amp is running under load and a short in the wiring occurs , the amp usually dies --fast. As long as you don't replace fuses and keep powering it up the damage is usually contained.

    There are other problems and causes that can happen , of course ; which is why it helps to deal with a servicer familiar with the brand that you have.

    4-6 weeks sounds like they want to replace the entire output and transformer assembly rather than troubleshoot the actual circuit. Any other brand and I would say that sounds wrong but some (but not all) Pioneer amps have a very strange output configuration making it almost impossible to use normal servicing procedures.
     
  8. Steve Berger

    Steve Berger Supporting Actor

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    Actually the protection circuits are there to protect the speakers from an amplifier short. (shorted outputs can put 60 to 100 volts at 8 - 10 amps accross a speaker winding ; destroying the speaker very quickly) Almost nothing is fast enough to protect the outputs from an instantaneous overload caused by a momentary short (wires briefly touching). At least with high power amps. With speaker wiring , neatness counts. Most output failures are caused by brief , accidental , crossing of the speaker wires. Overload protection works best if a short is present when the amp powers up. If the amp is running under load and a short in the wiring occurs , the amp usually dies --fast. As long as you don't replace fuses and keep powering it up the damage is usually contained.

    There are other problems and causes that can happen , of course ; which is why it helps to deal with a servicer familiar with the brand that you have.

    4-6 weeks sounds like they want to replace the entire output and transformer assembly rather than troubleshoot the actual circuit. Any other brand and I would say that sounds wrong but some (but not all) Pioneer amps have a very strange output configuration making it almost impossible to use normal servicing procedures.
     
  9. Chu Gai

    Chu Gai Lead Actor

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    You may never know why it went bad. Planned obsolesence comes to mind as does excessive heat. If you want to avoid speaker wires touching, and I happen to think that's a fine idea, then terminate your wires in either spades or bananas.
     
  10. Chu Gai

    Chu Gai Lead Actor

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    You may never know why it went bad. Planned obsolesence comes to mind as does excessive heat. If you want to avoid speaker wires touching, and I happen to think that's a fine idea, then terminate your wires in either spades or bananas.
     
  11. John Garcia

    John Garcia Executive Producer

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    Actually, I'd say shorting wires is the quickest way to fry an amp.
     
  12. John Garcia

    John Garcia Executive Producer

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    Actually, I'd say shorting wires is the quickest way to fry an amp.
     
  13. Michael R Price

    Michael R Price Screenwriter

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    It's impossible to hurt a speaker by shorting the output wires. The current goes through the wires, not the speaker and the speaker is muted.

    I once killed an amplifier by overheating on loud music, I couldn't tell you if it was an intermittent short or my cables were too capacitive. When it died the wires weren't shorted, so my speaker went "boomp." I mean the output stuck to a power rail before the fuse blew, so it was a pretty big boomp. I've never seen my woofers move so far. [​IMG]
     
  14. Michael R Price

    Michael R Price Screenwriter

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    It's impossible to hurt a speaker by shorting the output wires. The current goes through the wires, not the speaker and the speaker is muted.

    I once killed an amplifier by overheating on loud music, I couldn't tell you if it was an intermittent short or my cables were too capacitive. When it died the wires weren't shorted, so my speaker went "boomp." I mean the output stuck to a power rail before the fuse blew, so it was a pretty big boomp. I've never seen my woofers move so far. [​IMG]
     
  15. Chu Gai

    Chu Gai Lead Actor

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    Next time drop a tone arm on a record with the volume maxed out.
     
  16. Chu Gai

    Chu Gai Lead Actor

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    Next time drop a tone arm on a record with the volume maxed out.
     
  17. Mathhew+M

    Mathhew+M Auditioning

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    Well, in talking to one of the local service shops I may have found something that may have caused it, or at least contributed to it. I've always had my DVD player sitting on top of the reciever, for three years it sat there with no problem. One of the guys I talked to said this is a big NO NO, nothing should go on top of the reciever for at least 3-5 inches. My Toshiba player sits on feet that are probably about an inch tall, so there was room though not alot of it. It often got warm in my equipment rack, I wonder now if the amp just got too hot one day?

    In any case, I'm going to rearrange my stuff to put the amp on top, this will leave a good 8 inches or so between the amp and the roof of the cabinet. I may also just replace all the speaker wiring just to be safe.
     
  18. Mathhew+M

    Mathhew+M Auditioning

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    Well, in talking to one of the local service shops I may have found something that may have caused it, or at least contributed to it. I've always had my DVD player sitting on top of the reciever, for three years it sat there with no problem. One of the guys I talked to said this is a big NO NO, nothing should go on top of the reciever for at least 3-5 inches. My Toshiba player sits on feet that are probably about an inch tall, so there was room though not alot of it. It often got warm in my equipment rack, I wonder now if the amp just got too hot one day?

    In any case, I'm going to rearrange my stuff to put the amp on top, this will leave a good 8 inches or so between the amp and the roof of the cabinet. I may also just replace all the speaker wiring just to be safe.
     
  19. Patrick Sun

    Patrick Sun Moderator
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    Heat can shorten the life of electronics, so yes, the receiver could have simply over-heated and one of the parts finally failed.

    I had one channel from my 5-channel amp simply die on me, and the solution was to replace the IC board for that channel. Thankfully it was replaced under warranty.
     
  20. Patrick Sun

    Patrick Sun Moderator
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    Heat can shorten the life of electronics, so yes, the receiver could have simply over-heated and one of the parts finally failed.

    I had one channel from my 5-channel amp simply die on me, and the solution was to replace the IC board for that channel. Thankfully it was replaced under warranty.
     

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