Blown Adcom GFA 545

johnstown
johnstown Posts: 6
edited December 2004 in Electronics
Last Night my GFA545 died. Likely was my fault. I was using it for Kareoke and the distortion lights were on much of the time but we just kept singing. Using it to push an old pair of Polk SDA2 and a newer pair of Polk RTi 28's coupled using a Phoenix Gold SSM6 switch box. I have done this before but the last time letting the amp cool off fixed things.

No complaints with the GFA 545 but several questions. What did I do to it? Is it worth fixing? More practical if I Buy a GFA 5500 or GFA 5802 will they allow me to do what I want with the speakers I have? Which of the two would you suggest. Other equipment include GFR 555 reciever and GFP 555 Pre Amp.
Post edited by johnstown on

Comments

  • VR3
    VR3 Posts: 28,793
    edited December 2004
    It has like 2 or 3 fuses inside, Pop da hood...

    The fuse value, etc is on the fuses... Just look real close...

    Worth fixing...

    And stop pushing two speakers at one time you goofball

    Of course, you can always give it to me, ya know? hehe
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • johnstown
    johnstown Posts: 6
    edited December 2004
    Thanks a million or perhaps $1500. There were 2 4amp 250V fuses blown of course one for each channel. Will head to Radio Shack tomorrow for replacements. I did not knpw it was unsafe to drive more than one pair of speakers. At normal listening levels it never blew.

    How about the Kareoke. Is that abuse of a home stereo? Use the same input device to play CD's and DVD's It's a VocoPro.

    May still want to go up in power.

    Fred
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    Just make sure you watch the LEDS - even when they FLICKER, you need to back it off. PERIOD.

    Driving 2 speakers on that amp at loud volumes... eh, wouldnt do it...

    Now the 555 could handle it...Im sure
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • jcaut
    jcaut Posts: 1,849
    edited December 2004
    I was using it for Kareoke and the distortion lights were on much of the time but we just kept singing. Using it to push an old pair of Polk SDA2 and a newer pair of Polk RTi

    Bad, BAD, BAAAAD!! That's Polk abuse! I'm very surprised you haven't blown, at least, a tweeter or two. I'm not familar with that amp or its power capabilities, but if you're pushing it that hard, you need to consider: 1) A more powerful amp, and 2) PA speakers. There is a difference between pro sound/PA equipment and home hi-fi equipment, and in my book, Kareoke (or however you spell it) is not a proper use of your home hi-fi equipment. Yeah, you CAN do it, but it's only a matter of time before you fry something. At least go to Best Buy and get yourself a sacrificial pair of KLH or C-V's, instead of a classic pair of SDA Polks.
  • johnstown
    johnstown Posts: 6
    edited December 2004
    Have blown tweeters but only on the synthecizer passage of Toto's Rosanna (twice). Will probably buy a cheap PA to run the voice through in the future. My family does have a BALL during the holidays with the singing. We set up drums, an electric guitar, lots of food, beer , etc.

    Since I can fix my problem with 2 dollars worth of fuses I need to decide if this is an excuse to upgrade or not.
  • dorokusai
    dorokusai Posts: 25,577
    edited December 2004
    ALWAYS exploit a repair, into an upgrade.
    CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    yes, just make sure u send the broken 545 to me! ;)
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • hotwheelman
    hotwheelman Posts: 1,300
    edited December 2004
    I would hazard a guess that at the peaks you were hitting it was dropping the ohm load waaaayyyy into the zone that the adcom could not handle, thus the blown fuses. Were they wired in series or parallel?
    "Its worked so far but we're not out yet."
    "Hey big man let me hold a dollar"
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    Adcom is stable to 2 ohms... (from what I've been told)

    Musta been LOW

    Still way to much for that amp, regardless
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • hotwheelman
    hotwheelman Posts: 1,300
    edited December 2004
    Originally posted by Vr3MxStyler2k3
    Adcom is stable to 2 ohms... (from what I've been told)

    Really? I was thinking the manual for the one I had said 4 ohm.
    "Its worked so far but we're not out yet."
    "Hey big man let me hold a dollar"
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    May just be the 555 - I know atleast one of them is...

    :p
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • xsmi
    xsmi Posts: 1,798
    edited December 2004
    545II is stable down to 2 ohms. just check the manual for mine to make sure.

    he go figure.

    Does also say that multiple speakers can be driven in parallel butg be careful of the impedence because this does lower the impedence of both speakers. I definitly would not drive SDA's in that configuration though.
    2-channelBelles 22A Pre, Emotiva XPA-2 Gen 2, Marantz SA8005, Pro-Ject RPM-10 Turntable, Pro-Ject Phono Box DS3B, Polk Audio Legend L800's, AudioQuest Cable throughout.
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    If the 545 II is, then the original 545 is too - in my opinion, the 545 is just as much amp as the II if not more...
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • johnstown
    johnstown Posts: 6
    edited December 2004
    Thanks All. Back up and running for$1.69.
    Will be more careful in the future.
  • VR3
    VR3 Posts: 28,793
    edited December 2004
    Hey,
    Ur not the FIRST to blow fuses in those things ;)

    *How do you think I knew what was wrong* ? ;)

    Glad u got it all fixed! May you have many more years of listening!
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.