Go Back   Home > Forums > General Interest > Car Audio

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 20th January 2009, 07:59 PM   #1
diyAudio Member
 
Join Date: Jul 2008
Default Sub or Amp Blown

How do you tell if you amp or your sub is blown? My amp still powers up fine but there is very little sound from the sub. This happened after I blew a 30 amp inline fuse that was connected by the battery. The wire from the battery into the fuse area was loose and it melted the fuse holder a little bit. My 4 channel alpine V12 amp still works for my components, but my Pioneer Premier 2 Channel (Bridged) Amp is either blown or the sub is blown. NOT A GOOD DAY!! Any help would be great. Not sure what to do as I am not very good with testing. I can get an AC/DC tester to use if I knew what to do. I hope it is the sub and not the amp as the sub is a lower quality 12' MTX sub. Thanks.
  Reply With Quote
Old 20th January 2009, 08:20 PM   #2
diyAudio Member
 
Join Date: Sep 2006
Id check the sub first. There a few different ways to check it.
First gently push evenly on the cone of the sub and listen to see if theres any rubbing from the voice coil. the second is to get a multimeter and set it to the ohms setting and check the voice coils to see if it still measures the correct ohms. If thats all good look at the ground wire on your amp to see if its a thight connection. also check all connections (power,ground,remote and speakers, on that amp be sure they are tight and u have a good ground on the amp. after that if u still have a problem might be the amp
  Reply With Quote
Old 20th January 2009, 09:03 PM   #3
diyAudio Member
 
Join Date: Jul 2008
Can I test the sub with the multimeter (set at ohms) at the terminal connections on the box? My ground is good to the amp and the amps blue light does turn on when the stereo is turned on. Not sure what that means yet.

Can my (2) 30 amp fuses be blown at the amp and the power light still come on? I wouldn't think so but I will check those fuses tonight when I get home. They were too tight to pull out by hand so I will need to use needlenose pliers to get them out.

Also here is the big question...Can an amp blow something on the circuit board before the fuses on the amp blow? I hope it isn't the amp since it is new. I will test the RCA cables from the head unit with a 60 hertz signal. I did this once before when Babin helped me out. Thanks for the reply Mike.
  Reply With Quote
Old 20th January 2009, 09:44 PM   #4
jol50 is offline jol50  United States
diyAudio Member
 
Join Date: Nov 2007
Unhook the sub and touch the meter probes to the sub wires/terminals, if its a 4 ohm sub it would be 3.8 or something like that on a meter. Usually its a little under. If a DVC then check each coil separate. Fuses usually blow and you get no sound. Amp can fail inside for sure, check the sub and we will get to the amp. What you could do is also test the amp while you unhooked and tested the sub. Just turn the amp on and set meter to DC voltage, and see if there is any power on the amp where the speaker hooks up. There should be very little. You should unhook the RCA to it while you do that so no signal is going into it, of course change any wiring while its all shut off. If you don't find a problem there, hook it up and test the 12v DC at the amp, if it drops way down with any music you have a power wire issue yet, but the amp's power LED will usually die out if you do.
  Reply With Quote
Old 21st January 2009, 12:16 AM   #5
diyAudio Member
 
Join Date: Mar 2007
Using a meter to test the woofer will only tell you if the voice coil is still in tact. It is very possible for it to read 4 ohms and be frozen or sound really bad. To test the output of your amp you need to set the meter to AC volts.
__________________
If it ain't broke Don't fix it
  Reply With Quote
Old 21st January 2009, 03:56 AM   #6
jol50 is offline jol50  United States
diyAudio Member
 
Join Date: Nov 2007
If you have DC coming out of the amp it is broken for sure, would be easy to check. If no DC then it may or may not be broken.
  Reply With Quote
Old 21st January 2009, 01:32 PM   #7
diyAudio Member
 
Join Date: Jul 2008
The sub is fried. I am alright with that since it is an older sub that is a lower grade model. When I took it out of the box it smelled burned. I got a reading of OL on the voltmeter set to ohms and when I pushed the cone it made a grinding sound when I put my ear up by the magnet area. Thanks for all of your help everyone.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Blown amp pre-amp in or HU pre-amp out? scraph Car Audio 5 23rd January 2009 12:58 AM
mtx blown please help ADRIANd Car Audio 32 30th September 2006 11:35 PM
PPI 600.4 amp blown?? HELP!! D_Bull Car Audio 1 4th March 2005 05:18 PM
blown sub wharfrat Subwoofers 10 23rd May 2004 05:12 PM


New To Site? Need Help?

All times are GMT. The time now is 08:14 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2