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I've been noticing my amp cutting out after 15 minutes of driving and decided to check my connections. Every thing looked good but i noticed a whine playing through my subs. It's not the RCAs because I unplugged those and it was still whining. So it has to be something else. What do you think it is and how can I fix it. I already bought a Optima Yellowtop and it didn't help, would the "Big 3" help.

 
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Mine did that for a while too. I found out that I had disconnected my ground wires, and reconnected them in a bad spot.

 
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Yup your problem is ground.

 
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yea its grounding i'm pretty sure

 
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Change your ground location, and be sure to sand the paint down to bare metal for a good connection. You can put a coating over the connection afterwards.I had this problem, and it was so bad that my subs would thump on their own and all my lights dimmed severely.

 
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Thanks I moved th ground and the whining stopped. I still have a problem with the amp cutting off after 15 minutes. I think it might be overheating and cutting off. Do any of you have a problem with ventilation? I have the amp mounted to the back of the box near the base. Come to think of it the problem started when it got warming so that's probably it. Do any of you have an idea on how I could better cool the amp?

 
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check ohms.. I bet its wired at less ohms then the amp can handle.

 
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More info, what is your setup? How long have you had it, how long has it been cutting

 
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I've had it for about 5 months it's an MTX MXA-6001 300watt rms powering 2 infinity 12" 300watt rms subs. Everything was fine until about 2-3 weeks ago tried everything, lowered gains, checked connections, rewired, new battery, nothing has changed. Only thing I can think of is overheating since the amp goes into protection mode when it gets too hot. Only thing is our winter wasn't cold aroung 60s-70s wonder why it started now?

 
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OK, that amp is rated 300 Watts RMS x 1 channel at 4 Ohms or 600 Watts RMS x 1 channel at 2 Ohms. Now do you have single voice coil subs or dual voice coil subs?

If you have the dual voice coil, I am willing to bet they are wired to a 1 ohm load on that amp. Now if you have single voice coil, you have a perfect match.

 
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they are single voice coil so no problem there. I just don't know where I could move the amp if it's overheating. I've tried all kinds of places in the trunk same thing happens. Could a bad ground cause the amp to cut off for about 5 minutes after playing for 15 min. It sounds just like overheationg to me but I'm not sure. Where are the best places in the trunk to ventilate the amp? Or should I try putting it in the car and worry about thieves?

 
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alternator whine check ur ground. and why would u think that the optima would help? that **** runs off ur alternator when ur car is running. It could be that u r underpowering ur subs and that's why the amp shuts off. 1 amp sending out 300rm is underpowering the subs that handle 300rms apiece!

 
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That could be, but they've been running fine for the last 5 months. No problems what-so-ever then all of a sudden the amp cuts off and I'm like WTF?! I knew the optima wouldn't help the whine I thought maybe my battery was discharging to fast for the alternator to keep up and that's why my amp was shutting off. I changed the ground three times, sanding it down and everything, and that didn't help the whine. It's really starting to **** me off. I had no whine until about month ago then a week later the amp cuts off. I guess I figured it might be related since it all happened so close together. I guess I'll just take the amp back and get it checked out and replaced if I have to. Unless anyone has some useful advice?

 
Rep Power: 311

Why would underpowering subs cause his amp to shutoff?

EX2,
1. Does the amp have a protection LED light and does it come on when the amp shuts off.
2. Does it still shut off with your trunk open?
3. If you have an oscillating fan or whatever, try putting that on your amp and see if takes longer to shut down or doesn't shut down at all. Try putting your seats down and chilling your car with the AC for 10 minutes before using the amp.

How stupid, I don't think it has a protection indicator, does it?

Also, does it happen even while your not driving?
Narrow down the problem, see if it is heat. If so, see if it is internal or external heat.

 
Rep Power: 270

It doesn't have a light but I have tried playing it with the trunk open, seats down, AC blasting, and it happens whether I'm driving or not. It always shuts off no matter what I try to do to give it more air. The amp feels really hot after about 5-7 min then shuts off after another 10-15 min. I'll try the using a fan tomorrow to see if anything is different but I doubt it will be. You think the amp is frying on the inside?

 
Rep Power: 311

Sounds like it might be. Usually if an amp is overheating because of heat dispursion issues, you can figure that out by cooling it and monitoring. If cooling it isn't helping, it might be overheating internally - it might be F'd.

 
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yea overheating would be my guess... thats all bad bro. In my setup I have two computer fans running into and out of my amp box in the floor to keep the air circulating. May have fried the internals, but to see if that's it, drive with ur rear seats down to get better air flow and see what happens. let me kno if this helps

 
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oops i guess u already tried^^, u probably fried the internals bro..

 
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Damn that sucks. Guess I'll have to get the receipt from my friend and try returning it for a new one. I don't know where he got it but probably from CC since I've only seen them there. Thing is I don't have the box for it or anything else but I will have the receipt and I know he got some extended warranty for it. Think they'll take it back and let me get a new one or will they send it off to see if it can get fixed?

 
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if he has a service plan i think they will replace it on the spot and just take the box so that they can send in the broken one for credit. If he didnt and it's been more than 30 days, CC most likely wont help u. If it was w/i a year, the company that made the amp might fix it 4 u.

 
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You need to try running just one sub woofer and see if this helps. I am guessing you are just driving the amp to hard (To much load) Even though the amp is rated for 2ohm load most dont like it much.
I run a 1200watt RMS Sony Explode pro amp (very hard to get and also very exspensive they only made a few for comp. use) (Rated at 1600watts RMS at 1ohm) on one 12 Audiobahn pro sub (Sub is 2 voice coil 4 ohm each coil. Wired down to 2 ohm load amp is rated to 1ohm but when I ran 2 of them wired for 1ohm the amp did just what your is dueing

You may want to get a better amp (Higher amp ratting RMS of 500 at 4ohm load and 750 or more at 2ohm should due it) or only run one sub. Then your subs will only draw what they need and the amp will not over heat
Always set the gain lower so you dont blow up your subs. This will also give you a cleaner sound and is why you have Comp. show sound cars running 5000 or more watt's of power. Not just to get the most volume but to get a clean sound.
You may want to add a 1 fraud cap to the system as well this will keep your lights from dimming and alt from working so hard
I was an installer of stereo stuff for 4 years and we did some very cool stuff for sound off cars.
Just a tip from someone who has been threw this a lot back in the day.

 
Rep Power: 270

I took the just the amp back with no box and no receipt. They gave me $500 store credit to get any amp I want. I went ahead and upgraded a bit to the Kicker KX600.1 a lot better all around. Only thing is the bass level **** has different connections so know I have to go back and custom install a new one, no biggie. This amp kicks much harder than the MTX amp so I'm glad I went ahead with that. There are also no problems with this amp so you guys were right, the other amp was fried. Thanks alot for the help and advice.