subwoofer cutting out??

[Justin braaapp]

So the other day I was playing my system pretty hard when the sub cut out for the first time. it came back on almost instantly so I didnt think much of it until today when everytime I roll the volume up it cuts out and will come back on and then cut out again. I have a fi sp4 15 wired down to one ohm on a crescendo bc3500. Ive been running it on my stock alt which is a 120 amp alt with the big 3 and a xs d3400 as my second battery. I have a volt meter hopoked up and ive seen it drop to 11.8 twice in the time ive had this setup(about 5 months) but it is pretty much always in the mid 12's on heavy songs like decaf or djsnt and always at 14v on regular music like country/reggae. I havent had a chnace to check anything out due to work but I will when im off tonight. I took a quick look and saw that the heat sink on the wire coming out of fuse going from the second batt to the amp had melted into the fuse terminal. Im not sure if that would make the amp cut on and off but if anybody else has any suggestions I would really appreciate the help. Thanks ahead of time

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[Justin braaapp]

anybody?

 

[bubbagumper6 5,000+ posts]

You have nowhere near the electrical to handle that much power.

/thread

 

[Justin braaapp]

You have nowhere near the electrical to handle that much power.
/thread

Its been working for about 5 months. Is there a chance my sub or amp is broken now?

 

[Justin braaapp]

You have nowhere near the electrical to handle that much power.
/thread

and is there a way to check the amp to see if anything is wrong with it? it powers on and everything but on heavy bass notes it will cut out and come back on then go off for a second again

 

[bubbagumper6 5,000+ posts]

Its been working for about 5 months. Is there a chance my sub or amp is broken now?

It hasn't been working. There's no possible way with that electrical your amplifier has ever produced 3.5kw. You're dragging the system voltage down to your battery resting voltage and probably further than that. Your stock alternator is probably on it's last leg by now which would be why it's performance is degrading and your amplifier is going into protect. If you push that amp on your sub-par electrical you will destroy it. You need a much larger alternator and at least 2-3 good batteries (your stock lead acid doesn't count).

 

[Justin braaapp]

It hasn't been working. There's no possible way with that electrical your amplifier has ever produced 3.5kw. You're dragging the system voltage down to your battery resting voltage and probably further than that. Your stock alternator is probably on it's last leg by now which would be why it's performance is degrading and your amplifier is going into protect. If you push that amp on your sub-par electrical you will destroy it. You need a much larger alternator and at least 2-3 good batteries (your stock lead acid doesn't count).

I have an optima yellow top in the front and a xs d3400 in the rear. But is the amp broken completely now or as long as i unhook it until i get a better alt will it be fine?

 

[bubbagumper6 5,000+ posts]

I have an optima yellow top in the front and a xs d3400 in the rear. But is the amp broken completely now or as long as i unhook it until i get a better alt will it be fine?

Turn the gains down (way down). If it can still play at normal levels the amplifier is probably ok. It has protection circuitry to keep you from destroying it, it's going into protect because of low voltage, so if you don't go crazy with the volume knob, the system voltage will stay at normal levels. But with only 120A of alt power you have very little spare power, I wouldn't have even attempted an amplifier that large on a stock alternator.

 

[Justin braaapp]

Turn the gains down (way down). If it can still play at normal levels the amplifier is probably ok. It has protection circuitry to keep you from destroying it, it's going into protect because of low voltage, so if you don't go crazy with the volume knob, the system voltage will stay at normal levels. But with only 120A of alt power you have very little spare power, I wouldn't have even attempted an amplifier that large on a stock alternator.

I wish I would have been told that from the begining :/ most people said it should be fine until you have mpney to upgrade the alt. What size alt would you recommend for this amp? Thanks for your help by the way I really appreciate it

 

[Justin braaapp]

Turn the gains down (way down). If it can still play at normal levels the amplifier is probably ok. It has protection circuitry to keep you from destroying it, it's going into protect because of low voltage, so if you don't go crazy with the volume knob, the system voltage will stay at normal levels. But with only 120A of alt power you have very little spare power, I wouldn't have even attempted an amplifier that large on a stock alternator.

Also my amp is grounded to the secong batt and the second batt is grounded to the front batt. I heard this was a sufficient way of doing it but im not sure now?

 

[NASTY08IMPALA 5,000+ posts]

I wish I would have been told that from the begining :/ most people said it should be fine until you have mpney to upgrade the alt. What size alt would you recommend for this amp? Thanks for your help by the way I really appreciate it

Yea def not ok. Find out what/why that fuse holder melted and fix it ...then get ur electrical in check... i used to have a bc3500 and had to put my stock alt back on 125a while my mechman was being repaired ..i had a 55ah duracell up front and 2 110ah dekas in the back and it was not a very happy healthy setup..start sacin pennies and pray the bc didnt fry

 

[Bass4Days 10+ year member]

I wish I would have been told that from the begining :/ most people said it should be fine until you have mpney to upgrade the alt. What size alt would you recommend for this amp? Thanks for your help by the way I really appreciate it

I would recommend a 250-300 amp alt. I would recommend Singer Alternators.. Your amp isnt broken. It shuts off because its supposed to to stop it from breaking.

edit. You cant have any lights LOL

 

[Justin braaapp]

Yea def not ok. Find out what/why that fuse holder melted and fix it ...then get ur electrical in check... i used to have a bc3500 and had to put my stock alt back on 125a while my mechman was being repaired ..i had a 55ah duracell up front and 2 110ah dekas in the back and it was not a very happy healthy setup..start sacin pennies and pray the bc didnt fry

I don't see how it could be fried because it still playes just at higher volumes on heavy songs it cuts out

 

[Justin braaapp]

I would recommend a 250-300 amp alt. I would recommend Singer Alternators.. Your amp isnt broken. It shuts off because its supposed to to stop it from breaking.
edit. You cant have any lights LOL

Okay cool that was my one fear that my amp broke. I going to do what you said and turn the gain down a lot

 

[Bass4Days 10+ year member]

I don't see how it could be fried because it still playes just at higher volumes on heavy songs it cuts out

If it cuts out only on heavy songs You prolly mean low bass. Alot of people who have voltage issues low bass is when it will cut off. Must pull more current than higher hz tones.