Amp overheating....suggestions?

[dhauser]

Ok, I've got an MTX 275w Thunder amp powering two 10 inch Cerwin Vega subs in my trunk. The amp is mounted on a small, carpeted pedestal, with not much room between top of carpet and bottom of amp. It sits next to the sub box on the upper area of the trunk (back).

It shuts down after about 30 minutes (due to heat, as it gets very hot to the touch), then cuts back in and out every 5 minutes as the temp goes back up and down.

Aside from removing the carpet on the amp pedestal, what else should I do? Is the amp too small? Is that the problem? The sound is fantastic, and have had no other problems.

Suggestions appreciated. Eddie, where you at, man?

 

[Rollin]

Doug, I'm kinda confused "top of carpet and bottom of amp" Do you have your subs in parallel? Is your amp bridged? Is the gain cranked? If so a quick fix if you have some room, you can try some 1/4 rubber isolaters under the mounting holes just to increase heat dissipation around the entire amp, or even easier, depending on which Cerwin Vegas your running you can reduce the resistance the amp sees by running your subs in series or if running a 4 ohm DVC sub wire it to show 8 ohms. Lastly you could enclose the area around the amp and install a small fan(s) on one end to push or pull air. Course you can always turn the gain(s) down

HTH

 

[dhauser]

What I meant was there is not much "air space" between the carpet covering the amp pedestal and the bottom of the amp. Maybe additional spacers are in order to raise the amp off the pedestal better.

I have to admit I'm not savvy about the rest of what you said. I will look at the gain settings and see if it needs to be turned down a little. Does the gain setting just determine how much energy the sub receives, and thus how much current the amp is putting out? I'm a dummy when it comes to the electronic concepts in play here.

I'd hate to have to set up a fan for this set up; I'm hoping there's a better solution. Is my amp too puny?

 

[zam70]

An amp over heating is only caused by a few things. (what it's mounted on is not one of them )

-Running to low of an impedence load. (amp only stable to "X" and you're trying to run it lower)
-Bad power/ground wiring & connections. Your power & ground wires should be of the same ga size (to play it safe) 8ga minimum no matter what size the amp. 8 ga should be fine for the MTX. Your amp ground wire is only as good as you battery/chassis ground...did you reground the batt/chassis.
-improperly set gains & bass boost (set to high)
-bad air circulation
-POS amp (the MTX is not)
-bad electrical voltage.
or:
YOU'RE PLAYING IT TO LOUD TO LONG...

 

[GNandTTA]

If you do measure the voltage make sure you have the system playing at full tilt. That's the only true way to determine if you have an electrical problem. If the voltage is low, look at the ground first, it's usually the problem.

 

[TylerKelly]

A half inch isn't a whole lot of room for venhilation, and the simplest fix may be to raise the amp up a little bit to get a bit more air flow and cooling going on. The gain being too high would cause more signal running through the amp which (I think, not sure on this) is like running more electricity through a wire (well, thats exactly what it is come to think of it). There's too much action going on in the internal wiring of the amp, and it gets warm. One way of saying it is that by having the gain too high, there is too much friction between the electrons in the wires, and friction creates heat, and heat causes amp shutdown. (Thats a pretty oversimplified way of putting it, but you get the idea.)

Tyler

 

[dhauser]

Thanks for the comments. I've tried turning the gain down significantly, and it didn't help. No change at all. Next will be trying to raise the amp off the pedestal more to get more air running through there, but I don't think that's really it either. Haven't checked the ground, but I made sure it was a clean solid ground when installing it initially. Don't know why that would've changed.

 

[TURBOV6]

The way you mounted the amp should be fine its like mounting under a seat..The amp heat sinks should be adequate to disapate heat. Souns like you have a too low load on the amp causing it to over heat and go into thermo load..

How did you wire up the subs? Dual voice? 4 or 8 ohms subs?