high volume dims lights

    I have 92 civic with alpine cda-9533 head unit runnin its internal amp to speakers, and a mtx 342(supposly 200-300 watts rpms) 2 channel amp to 1 12 (200wattsrpms)inch mtx thunder 5000 sub.
    
    When i first installed the system it sounded really nice the bass sounded clean, but the problem was that i had to turn the gain near the max in order to get good bass. Have been running the amp like that for at least 1 year and 2 months and finally i blew a the powerline fuse(25amp) near the battery, I've been told thats a really small fuse but this never happen before so i thought that the amp got hot and turned off(happens once in awhile after long plays. Then I finally found out it was the powerline fuse. Replaced it and everything sounded the same as before, but after a few days i noticed at high volumes around 20 it dims my parking lights and headlights when the bass hits. Soon I was blowing more fuse at least 2 or 3 more with 30 amp fuse . It didn't really bother me but one day when I was having the volume at 20 and it shuted my amp off for a min and came back on, now the bass sounded really weak like there's not enough power, but it still dims my lights. The wierd thing is that it still sounds nice at lower volume say around 15 but anymore higher then that the bass sounds weak and distorted.
     
    I'm pretty sure the amp is screwed by running the gain too high, but just today i swap to another amp to determine if it was really the amp or not, it was a cheap Jenson amp about 200 watts rms. After the swap it clearly showed a difference, when i turn it over 20 on the headunit there was still enough energy that the bass was not weak, it was as loud as the mtx when it wasn't screwed but sound quality wasn't as nice as the mtx. The problem is that at high volumes it still dims my lights.
    
    My questions is why does it still dim my lights? I had the mtx over a year and it never done that until just recently. Anyone think something is wrong with my electrical system, maybe the alternator going weak? Im not worry about my mtx amp at all just wondering why my lights are dimming when It never has done it before. Hope ya can help me out thanks..

I meant alpine cda-9833... up

Yes, I'd definitely get the alternator checked out.  I think factory it's rated at 60 or 70 amps.  It's got some age, and with the cold, you've got your heater controls on high, with your headlights on, drawing plenty amps, not to mention blowing 30 amp fuses for the sub amp.  I'd suggest making a trip to AutoZone to have it checked for free. 

Also, consider upgrading your headunit to something with a higher preout voltages (preferrably 4 volts or better) so your amp doesn't have to work so hard and you can set the gain at a reasonable level.

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My ex once told me I have a perfect face for radio.

yea, i'll have the alternator checked soon. But is there anything else that i can do, if the alternator checks out fine? Would a capacitor elminate the light dimming? thanks

uppy...

No, a cap will compound the problem. Remember as well that it is now getting colder out and energy bleeds of even faster. Electricity is an algebra equation, what you do to one side you must do to the other. You have a good solid power line for the amp, what has been done to the ground wire and the factory grounds connections at the battery to chassis, battery to alternator etc.? This needs to be looked at asap. I would also have a good long hard look at the battery while you are at it.

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