Anybody use this amp? alpine mrp-f240

[nabissssco 10+ year member]

Hey, I've got this 4chann amp and it sounds fine and has good sq but after being played for a while it starts to really heat up and actually went into protect a few days ago. I have it bridged, the gains are correct, and its ran off 8ga wire which is plenty for 200wrms. My question is if this is normal for the amp, normal for a/b amps, and if this is just what 100w per chann gets you? I'm thinking I need to get a bigger amp?

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[jpexpc 10+ year member]

What are you pushing with this amp? If you're running 2 SVC 4 ohm subs in parallel and bridging the amp then you would definitely have some heat issues. You need to determine what the final load is because your amp is only 4 ohm stable when bridged.

 

[nabissssco 10+ year member]

Yo, I'm so sorry for not getting back to you for a while, I went camping and I kept getting no answers so I just stopped checking. I'm using the amp to run my front comps which are both 4ohm each so that's setup correct. I stopped by a shop to talk to a guy and he said that the amps prob good and everything is installed correctly based on what I told him and what he saw, he said that it just thermal'd out because it was too hot. It still plays and sounds good, I now have the gain set lower than I did b4 with the vent fan blowing air on it at all times, the amp is under my seat and a ventis there so why not. Thanks again man.

 

[AlterEgo99 5,000+ posts]

Yo, I'm so sorry for not getting back to you for a while, I went camping and I kept getting no answers so I just stopped checking. I'm using the amp to run my front comps which are both 4ohm each so that's setup correct. I stopped by a shop to talk to a guy and he said that the amps prob good and everything is installed correctly based on what I told him and what he saw, he said that it just thermal'd out because it was too hot. It still plays and sounds good, I now have the gain set lower than I did b4 with the vent fan blowing air on it at all times, the amp is under my seat and a ventis there so why not. Thanks again man.

I've got 2 Alpine PDX amps, mostly due to my limited space in my otherwise very large '08 Silverado. I like them as they are Class D and run cooler but I did have to install a couple of cooling fans to help keep them from getting too hot. Class A/B amps are going to run hotter.

 

[nabissssco 10+ year member]

So than that's normal heat from the a/b amp than. That B was hot.

 

[AlterEgo99 5,000+ posts]

So than that's normal heat from the a/b amp than. That B was hot.

Well, prior to my new truck I had a JL Audio Class A/B amp powering my subs and that baby would get hot very quick...ended up selling it on eBay and getting a JL Audio Slash v2 Class D amp and that bad boy never even got warm...and it could crank out the powa! //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif So, I can attest to Class A/B being toastier than Class D.

 

[nabissssco 10+ year member]

Cool, thanks. That's what I thought but I wanted to make sure. My jbl 600.1 never gets hot and I've used the sh!t out of it a few times. I'm just gonna keep the gain low and keep the vent blowing air on it, so far its been ok since I've been doing this for a week or so.

 

[AlterEgo99 5,000+ posts]

If it starts going into protect mode, THAT will be the time to panic. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[nabissssco 10+ year member]

Lol, it actually did one time. It did it after I had the amp bridged. Since I've adjusted the gain down and had the fan on its never done it again and it was only the one time. I also had rca's from the hu for front and rear running into it while being bridged but the owners manual said to use just the front rca's with splitters into the amp so that's what I did. With all that new stuff done it seems fine now.

 

[AlterEgo99 5,000+ posts]

You may also want to use a DMM and check the voltage at the amp when you are really pushing it. If there is a voltage drop then that can also cause the amp to heat up more than normal. Typically the "Big 3", new battery or HO alternator will correct the issue. I'd troubleshoot in that order as the "Big 3" is the cheapest route.

A less high tech route to see if the voltage is dropping (if you don't have a DMM - they are only about $20) is to simply crank the tunes and turn you vehicle lights on high beam...if they dim, you probably need to beef up the electrical as I suggested.

If the amp consistently doesn't get adequate power, sooner or later it will go "poof". //content.invisioncic.com/y282845/emoticons/lightning.gif.3313d59263b518d6d89ddcbfead237d0.gif

 

[nabissssco 10+ year member]

thanks man, ill give it a try.