Alpine amp problem

[docutech 10+ year member]

I posted a thread in the General Discussion forum about a SQ issue. Many helpfull folks chimed in with suggestions as to what I could do to remedy the problem. The full thread is here:

http://www.caraudio.com/forum/showthread.php?t=225723

I took the advice of immacomputer:

I would disable the crossovers on the headunit and play with the crossovers on the amp. I wouldn't trust what the numbers on the amp say though. I would play around while listening to music and see if you can get some improvement.

Now my 4 channel amp cuts off after several minutes on volumes above 20. The display shows "CUR" which, according to the manual, means that there is too much current being fed to the amp.

HU= Alpine CDA9855

Comp Amp= Alpine MRV-F545

I have set the HU back to what it was and everything seems fine now but I would like to know why the amp just cuts off. Any help would be appreciatedl

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[ledzeppac 10+ year member]

I posted a thread in the General Discussion forum about a SQ issue. Many helpfull folks chimed in with suggestions as to what I could do to remedy the problem. The full thread is here:http://www.caraudio.com/forum/showthread.php?t=225723

I took the advice of immacomputer:

Now my 4 channel amp cuts off after several minutes on volumes above 20. The display shows "CUR" which, according to the manual, means that there is too much current being fed to the amp.

HU= Alpine CDA9855

Comp Amp= Alpine MRV-F545

I have set the HU back to what it was and everything seems fine now but I would like to know why the amp just cuts off. Any help would be appreciatedl

After reading for the last month it seems that the Alpine f450 and similair models have issues going into protect mode....//content.invisioncic.com/y282845/emoticons/*******.gif.a649d21efc0d1fd4890a6428166586c1.gif

I had one for 2 days and all it did was go into protect mode. It got REAL hot fast too

 

[o2 SENTRA 10+ year member]

The reason the amp is going into protect mode is you are getting down into the 11 volt area on the spiking of the amp.I currently own the mrp 450-f and the mrd 1005 is on my JL 12w3/3-4's in their vented enclosure.I upgraded from the mrp 650 m to the 1005.Only once did my systen go into protect mode and I had been parked for an hour playing my unit veryhard w/the motor off.Battery went to an 11 volt low spike.I was in front of my install shop and I heard this straight from Mike the managers mouth.They install Alpine,JL,Pioneer,and Kenwood.I also run 4 type -r- 6.5 co-ax with the cross overs and then tweeters from the type r component set running from the 450-f.The head unit is the 9847 Alpine.Adding the tweeters made all the difference in the world along w/the crossovers.02 SENTRA-out

 

[docutech 10+ year member]

The reason the amp is going into protect mode is you are getting down into the 11 volt area on the spiking of the amp.

//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

Are you saying that I am starving my amp?

Interesting hypothesis. My HU displays the voltage to be above 13.5V with volume well above 20. Also, the amp goes into "CUR" protect meaning there is too much current being fed not too little.

 

[chucku 10+ year member]

//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif
Are you saying that I am starving my amp?

Interesting hypothesis. My HU displays the voltage to be above 13.5V with volume well above 20. Also, the amp goes into "CUR" protect meaning there is too much current being fed not too little.

I would think it would go into cur protect mode when the voltage drops, not increases. If your getting too much current, then youir voltage reg could be going bad? Just a guess.

 

[docutech 10+ year member]

 

[Ricky616 10+ year member]

my cousin has a alpine mrv f345 and when he would raise the volume past 24 it would shut off as well, Because his sub amp was pulling to much current. The problem was he was starving the amp. Hope this helps //content.invisioncic.com/y282845/emoticons/fro.gif.c695f1f814b01c4ad99fe7f8cccadd29.gif

 

[docutech 10+ year member]

So, with my HU crossover set, the amp is puling less power?? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[shovelhd 10+ year member]

You have a fundamental misunderstanding on how amplifier power is made and how current flows. An amp is not force-fed current. Voltage is a potential to make electrical energy. It can't create it on it's own. Current is electrical energy flowing to make work, i.e. power. It can't flow on it's own. Nothing is pushing the current to your amp, rather your amp is demanding more than it should.

Power in watts = Volts times Amps

In order to put out the same power, an amp will demand more and more current as the voltage drops. If your amp did not have protection circuitry, it would keep demanding currrent until it blew up or blew a fuse. Your "CUR" light is telling you that the current demands are higher than the amp can handle, which generally means one of two things. You either have too low an impedance load on the outputs (subs wired wrong, shorted coils, etc.) or the voltage AT THE AMP is getting too low during the big hits. Get out your DMM and measure it to make sure.

 

[Grim 10+ year member]

I have that and a M1005...

I found that I ran into that problem as well, turned out to be a faulty ground.

However, that was at any volume when it was cranked, it was random and would only happen with large bass hits. So i dont know if that really sounds like your problem.

It then started happening at a specific volume with my m1005. After some searching around I found out that alot of folks have that problem when they are sending a clipped signal...I pulled out the DMM and set it correctly and havent had a problem yet..