subs got quieter
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=106501
Printed Date: June 01, 2024 at 10:42 AM
Topic: subs got quieter
Posted By: draggin waggin
Subject: subs got quieter
Date Posted: August 01, 2008 at 12:05 AM
Here's the scoop, I have two 2 ohm type r alpine's wired at 2 ohms to a m1000 alpine amp. The amp get extremely hot and has gone into thermal protection several times. My grounds are good so it's not that.
But now, the amp doesn't get hot at all and my subs don't sound like they used to (they're very quiet)
Any ideas why it's doing this?
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Replies:
Posted By: aznboi3644
Date Posted: August 01, 2008 at 12:51 AM
what is the voltage...seems like a low voltage problem to me. Also seems like the amp may be **ed
How do you know your grounds are good??? Have you verified with a DMM??
Posted By: draggin waggin
Date Posted: August 01, 2008 at 12:56 AM
The voltage is 12.8
I measured all the grounds and they all come up as .1 ohm
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Posted By: i am an idiot
Date Posted: August 01, 2008 at 4:43 AM
You need to check the voltage with the amp playing as loud as you usually play it. Checking the voltage with the amp at rest will tell you nothing. No current draw = no voltage drop.
Posted By: draggin waggin
Date Posted: August 01, 2008 at 4:50 AM
I make sure to do that then. What should I look at if there is a voltage drop.
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Posted By: draggin waggin
Date Posted: August 01, 2008 at 8:47 AM
Alright I metered it, and there is a voltage drop. When it plays around the level I usually have it at (loud) the voltage goes from 12 to 11.8, mostly around the 11.9. The alternator has a 14.4 voltage rating. What could be the reason.
BTW- I am replacing the alternator with a better one. Right now it's an ebay 160 amp, so I'm getting an Iraggi 200 amp.
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Posted By: draggin waggin
Date Posted: August 01, 2008 at 8:56 AM
I'm very sorry to post again but I ran out to check the alternator voltage with the system running and it came up around the mid 12s (12.4, .5, .6 etc)
So I would assume it's the alternator being overloaded?
I do have one more question- how many amps do my amps draw?
MRP-M1000 at 2 ohms 1000 watts 70% efficient
Rockford 400-4 4 ohms 400 watts 70% efficient
Oh and my battery is new, it's an optima yellow top
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Posted By: DYohn
Date Posted: August 01, 2008 at 9:08 AM
System voltage dropping below 12 indicates the ALT is being overloaded, although 11.8 is not that bad. Yes, a higher output will help that problem. You say your system was working fine but the amp was getting hot, then suddenly the SPL level is down? That doesn't sound like a voltage problem, that sounds to me like your gain was way too high and the amp was clipping and you may have damaged a voice coil ------------- Support the12volt.com
Posted By: draggin waggin
Date Posted: August 01, 2008 at 9:16 AM
The gain was set on the amp at NOM (it's written on there) and this morning it sounded like it normally does. Yesterday it seemed real quiet
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Posted By: DYohn
Date Posted: August 01, 2008 at 9:38 AM
draggin waggin wrote:
The gain was set on the amp at NOM (it's written on there) and this morning it sounded like it normally does. Yesterday it seemed real quiet
You need to read and follow the instructions in the "How to set your gains" sticky post. ------------- Support the12volt.com
Posted By: draggin waggin
Date Posted: August 01, 2008 at 9:47 AM
Okay I will make sure to, I originally set it so that I didn't hear any distortion but I will double check.
So I will
-Upgrade Alternator
-See if I can shorten my ground for amps
-Reset the Gain
I want to thank you for your help, and sorry if I sounded cooky or anything.
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Posted By: DYohn
Date Posted: August 01, 2008 at 9:49 AM
No prob. Hopefully your voice coils are OK. (BTW I would reset the gain first since it's the easiest to do of the things on your list and won't cost you a dime.) ------------- Support the12volt.com
Posted By: draggin waggin
Date Posted: August 03, 2008 at 12:40 AM
I reset the gain but it still acted up.... but I found out the real problem.
Just as I was about to take out my subs to check to see if the VC was blown, I thought to check my wiring. A signal cable was loose. So I fastened it back and my subs were back to normal.
Dodged a bullet I did
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