I have an 2010 12" alpine type r running on a Mrp-m500 at 2 ohms. When I turn it up the sub starts to smell and get extremley hot on the cone surface. What could be the problem, because I'm sure its not normal

 

Set your gains properly

It's getting hot and stinky because you're clipping the hell out of the signal

 

+1 your gains i imagine you have all the way turned up. Your sending raw dirty power to the sub. If u dont back it down you will blow it soon, if u haven't damaged the coils already

 

the gain is only less than half up and bass boost is all the way down

 

Is your sub a 4ohm or 2ohm sub?

 

He said it's running at 2 ohms. So it haz to be a 4 ohm sub.

 

Doesn't matter how high up the gain is you have to match the gain to the pre-out on your deck. Go to ace and pick up a cheap volt meter for 15 bucks and do a little math volts=sqrt(power*resistance). So for example:

sqrt(500w*2ohms)
31.62v

so put on a 50hz 0db sine wave (google) and turn your head unit up 4/5 of the way put the volt meter in the speaker outputs on the amp and dial the gain lpf and so on till you get 31.62 volts and you will be set.

 

cranking up the gain to compensate for power that isn't there=clipping.

clipping=heat

clipping=death

 

true dat get a bigger amp set the gains low to give her clean powa and ur good to go.

 

the amp is mounted on the box, would it be easy to install a new amp using the same wires?

 

No. That can just make the problem worse if the voltage isn't there to power a larger amp, the amp that he has is fine for the sub, and a gain knob is not like a volume knob and cannot be adjusted to be lower to give it less power.

 

Let's think about this for a second... what is a subwoofer? Its a coil and a magnet. The magnet is not going to heat up so the only thing left is the coil. A coil on a subwoofer is not going to get hot unless there is current passing through it. A thought going through my head is, is this a dual voice coil sub? And if so, have you wired it correctly? It is possible to wire the coils out of phase with each other, which would be interesting to see how long the sub could last before it blows up.

So, OP, is the sub one coil or dual coil?

 

yes

 

its a dvc

 

Ok, so given it is a dual voice coil, why not pull the sub out of the box, double-triple check the wiring, and make sure they are in-phase with each other? You will be looking for a parallel connection here because you are after a 2ohm final load, which will be ideal for your amp assuming each coil is 4ohm.

Coils are quite simple, they shouldn't overheat unless there is something very wrong.

 

Wrong u tard. Setting the gains lower on a smaller amp thats not being strained would be better on the sub than crankin them on a smaller amp. Can anyone back me up. And what audio setups have you had. I imagine my past ones crap on yours. Just sayin though.

 

It doesn't matter. The coil won't heat up, the amp would. My bet is something is up with the DVC concept.

 

I got Alpine Type R. Played around and did turned all the knobs up. Yes the amp does heat up but it works fine. Obviously I don't keep it like that all the time but was just something I wanted to try out. I'm running a rockford amp.

 

Dude if you want to bash me go ahead I'm not well known on this forum but I've only got my MECP, compete with DC Audio and have a legal 144.7 sealed at the dash in my Acura Tl off a pair of 12s, and have installed over 100 systems out of my garage. An amp is designed to put out a certain amount of power at a certain ohm load and will constantly be trying to make this power whether or not the gain is set higher or lower. The gain is not a volume control.

But go ahead don't listen to me cause what do I know?

 

Well you are dead wrong.

But I think you meant right. You left out the part where the input to the amp would need to be a certain amount as well. The amp is not constantly trying to make power, it produces power based on the signal from the source, by copying it in a pre-amp stage and amplifying what is sent to it. So for a given INPUT into an amp, the gain knob will control the GAIN off that input. And it definitely is not a volume knob. Care should be taken so the output from whatever source you are sending to the amp does not clip or over-drive the amp's pre-amp stage (hard to do with modern amps), and for that given source input, the gain should be dialed in so the amp is not clipping its outputs either.

www.bcae1.com can teach a lot.

 

Sorry man but 144 isint gonna impress me at all. Was doing 147 off a pair of crappy rockford hx2's. You can say you have installed this and made that. But hey whatever gets you sleep at night.Not sayin you dont as I really don't care. I have pictures and build logs to prove my work. No the gain is not a volume knob did I say it was? Nope.

And fourthmeal I'm starting to love you and your knowledge lol.

 

I'd like to see the TermLab scores for that... Anyway you obviously do not know what you are talking about or are completely insecure as to what you are saying if your "best knowledge" is to come and try to bash me. Why would you even say to get a larger amp when the RMS on his amp puts out the recommended RMS for his woofer when the gains are set properly?

Anyway to the OP who started this thread the best option for you to do would be to set the gains properly on your amp, if the sub is getting clipped by the amplifier that is what is causing it to get hot and smell. The clipping can be caused by a number of things from head unit issues, source music being clipped, the gain being set too high, or the voltage dropping too low. Upgrading the amp will cause more strain on your electrical system and would likely make your voltage drop lower and clip your woofer more.

 

Your thoughts are correct for the AMP, but not the woofer. The woofer is a coil and a magnet, nothing more. The AMP will heat up beyond thermal capacity if sustained clipping is encountered (for the fact that a clipped signal approaches that of a square wave which contains 2x the power of a sine wave.) A true square wave at audible frequencies approaches the "un-listenable" category so I doubt this is happening. But the speaker should not heat up beyond power handling RMS thermal levels even with this abuse! Something else is happening.

 

This explains it mathematically and acoustically.

http://www.youtube.com/watch?v=y6crWlxKB_E

 

thank you very much for all the insight...could it possibly be a breaking in process? I have no idea when it comes to subs