Blew car amp, need some help

Discussion in 'OT Technology' started by unrealii, Oct 7, 2002.

  1. unrealii

    unrealii professor of plant biology

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    I blew my mtx 5400d, 5 channel amp. Here's the thread with the details of my install. Only the sub channel went out on me. I thikn I may have over powered it. I wasn't getting any bass from the 4 channels from my factory amp, so I hooked a high low converter to the output of my factory sub amp (it's a little dinkly thing on the back of the factory 6 by 9 sub). It worked well for 3 weeks, now it just crapped out on me this morning. I heard a few lound thumps from the car and was like oh shi. I checekd the sub, nothing seems to be burned. I checked the amp by giving it a different input and when i touch the gain for the sub, the sub goes boom boom. I removed all inputs from the amp, and the sub still goes nuts when i touch the gain.

    I was wondering, how do I test how strong of a signal is comming from my sub amp. The mtx can handle 8Vrms. Can I just hook a multimeter up to the rca from the loc?


    Here are some details of my system:
    mtx 5400d amp, 270 watts rms to sub @ 2ohms, gain is set to 60%-65%, thunder eq at 85%
    ebc knob, was right at 50%.
    bass on factory taurus jbl deck, <40%
    bass signal feed through Install Edge (division of Rockford corp) High low converter off of sub amp, gains on loc at 40%
    Image Dynamics IDQ10 V2 D4 sub, wired in parallel for 2 ohms, rated 250/500 watts (rms/max)
    .55 cu feet sealed homemade box
    12 ga pheonix gold wire

    Thanks in advance for any help.
     
  2. idontgiveashit

    idontgiveashit I eat rice

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    if it went shit, i always bring it back and say it flickers on and off, therefore they cant test it to prove you wrong, and have to give you another one.
     
  3. unrealii

    unrealii professor of plant biology

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    It's already out of the 30 days from good guys. I think I'm going to send it to mtx, get another one, then take it to goodguys and say it's working fine and get them to warranty it, so if this happens again, I get a new one instantly.
     
  4. flynfrog

    flynfrog Cool isnt Cheap

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    you might be cliping the signal form your factroy sub amp to your mtx
     
  5. unrealii

    unrealii professor of plant biology

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    Yeah, that was the only way to get bass out of the system.

    I'll try workign with the signal before the sub amp since it is built on the sub and not part of the actual radio amp.
     
  6. unrealii

    unrealii professor of plant biology

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    found out today that they replaced all of the mosfet chips. Any way to prevent a future reoccurance? I told them my setup and he told me to turn down the thunder eq and the gains from the high low converters. It was probably distortion from my input sources which caused it. I guess I'll have to turn the gains up on the amp a lil bit.
     
  7. flynfrog

    flynfrog Cool isnt Cheap

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    i wouldnt turn the gain up much on them amp those are not volume contorls start wiht them all the way down on every thing then slwoly work them up till you start to hear distortion then back it down do this with the system at full volume
     
  8. unrealii

    unrealii professor of plant biology

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    Got the amp back. It works great. For me, if I turn the volume at 40%, I can start hearing distortion. However, at 40%, that would be loud enough for me to be driving 100 with all the windows open.
     
  9. flynfrog

    flynfrog Cool isnt Cheap

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    now dont let your freinds crank it up
     
  10. unrealii

    unrealii professor of plant biology

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    Yeah, when I had originally installed it, I showed it to my dad, he was like, I dont hear anything and cranked it up. I slapped his hand away from the knob and turned it down withing a fraction of a second :slap:
    Yeah, I need to watch out now. I have a 5 year warranty through good guys so it's all good.

    I was listening today and all of a sudden my front left channel goes out on me. I'm like wtf. I kept the radio off and turned it back on two hours later, it worked fine. I inspected the amp closely when I got it back from mtx and I think they just threw a refurbished board in there. It had dust all over it, knobs were scrached up and not as easy to turn when I bad bought it, and the screws on the terminals are all jacked. :squint: They claimed they replaced only the mosfet chips.
     

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