View Full Version : My amp turns on but my subwoofer doesn't???



The_Answer
09-19-2009, 01:33 PM
Like my title states, I'm having some trouble with my subwoofer.
I have an Alpine Type R 12", and Alpine amp and an Alpine headunit.

The story:
My subwoofer was working fine on Wednesday then I took it in to get 2 new tires so I took the subwoofer out. I put it back in the next morning, and now it doesn't work. However the amp turns on. I checked the wiring to the amp and to the sub. Everything looked as it did before. I'm not too sure what is wrong. Any suggestions will help! Thanks ahead of time!

Taco15
09-19-2009, 02:33 PM
check your RCA's and remote wire.

do hear anything coming out of the speaker when the amp turns on?

The_Answer
09-19-2009, 02:57 PM
I don't hear anything, it's completely silent. I checked the wires and they seem to be fine.

luke81
09-21-2009, 08:41 AM
When you removed the woofer did you pull the fuse from the amp? If you left it on, is there any chance the speaker wire touched each other and shorted?

HaViKTypeR
09-21-2009, 12:14 PM
When you removed the woofer did you pull the fuse from the amp? If you left it on, is there any chance the speaker wire touched each other and shorted?

^^^Yea im thinkin u shorted the amp bro, if all wires and connections are fine try connecting another sub just to check and u'll kno if its the amp or the subs........

The_Answer
09-21-2009, 08:33 PM
Thanks for the replies guys! I didn't remove the fuses when I took the sub out. I hooked up another speaker and it didn't work either. I changed all the fuses yesterday and still nothing(2 on the amp, one for the power supply). If it shorted out, how do I go about fixing it, or am I screwed and have to buy another sub?

Taco15
09-21-2009, 10:06 PM
install another amp and see what happens. You very well could have shorted the remote wire or something.

go take it to an audio shop and have them test it.

The_Answer
09-21-2009, 10:47 PM
I will be doing that next week, I'm going out of town this weekend and don't really have the time. Thanks for the help!

The_Answer
10-01-2009, 01:13 PM
Took it to divine sound. They said they tested everything and they also said my subwoofer wasn't plugged in inside the box...but I KNOW it was. They told me I fried the outputs from my amp, but wouldn't the fuse go first? They were done in 10 min checking so I highly doubt they tested the wires. I would have talked to them more but I was at work when they checked. Any other help??????

EclipseGT01
10-01-2009, 01:19 PM
Not really. If you are running a 2 channel amp, and running two 4 ohm subwoofers running parallel, and then bridging it, you are then running the amp at 2 ohms rather than 4 ohms where it is stable bridged, and you can blow a channel. Did you have a 2-channel or a mono block?

GradeA_TireFryer
10-01-2009, 01:28 PM
Took it to divine sound. They said they tested everything and they also said my subwoofer wasn't plugged in inside the box...but I KNOW it was. They told me I fried the outputs from my amp, but wouldn't the fuse go first? They were done in 10 min checking so I highly doubt they tested the wires. I would have talked to them more but I was at work when they checked. Any other help??????


first problem - Took to Devine,
and blew the outputs would happen if the wires inside box touched, or sub vc has gone bad.

when you removed your sub - did the speaker wires touch each other while amp was on? this can cause your problem.

luke81
10-01-2009, 02:11 PM
when you removed your sub - did the speaker wires touch each other while amp was on? this can cause your problem.

Yep, exactly. Some amps are smart enough to shut off, or go into a protection mode when they sense a short. Other amps will just try to flow current into the short until the outputs explode, which takes almost zero time to happen. The fusing on the amp wont usually protect against this. The fusing is on the DC side of the amp, and when the speaker leads get shorted the outputs will explode before the power supply even knows what is going on.

The_Answer
10-01-2009, 02:39 PM
well divine was free because they installed my head unit. not going there again. the amp is an alpine monobloc 400w amp. im not sure if the wires touched but it definitely could have happened. so im pretty much looking at buying a new amp?