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Discussion Starter #1
I've searched the forums with no luck on my issue, sorry for posting a troubleshooting thread here but I can't find a proper place for it.

I have my suspicions on what's wrong but I want a more educated input. I'll make this as simple as I can.

I'm running:

JL 300/4 v2
-JL C5-570 Components in front
-JL C2-570 Coaxials in back

All speakers are tuned pretty low (maybe 75%), Input sensitivity is all the way down with High pass set to 80 Hz on all channels.

All new wiring was used for all of them. Brand new Stinger wires and RCA

Was installed at an Authorized Dealer, All speakers and Amp were brand new from JL


My problems :

-Last week my C5s started cutting out completely and coming back on and my back C2s were only playing. It's getting worse. When the C5s cut out the C2s go haywire and increase in volume on their own

-Also, sometimes increasing and decreasing the volume each 'notch' causes a barely noticeable 'pop', even at low volumes.


Sorry to create yet another bullshit 'please help me' thread but I'm desperate for resolutions just weeks after spending the money.
 

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Discussion Starter #3
my first guess was the battery as well, but if i remember correctly a few weeks ago both of my amps were getting enough power according to my dealers digi MM
 

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That was a few weeks ago ;)

I'll bet that you could bench press a really heavy weight several times...but eventually your arms would give out and you'd stop !
 

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Discussion Starter #5
i'll check it out tomorrow. i don't know how a measly 300/4 and a 250/1 could cause a problem, even though i don't listen to it that loud.

oh well, as the owner of a 69 chevelle i know firsthand that cars have a mind of their own and will do shit like that on the drop of a dime
 

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What kind of car is it??

I know some of the modules used on newer cars like the new toyota's and dodge's can sometimes have a mind of there own and do the same thing you are describing...Front speakers cutting out, back speakers going crazy, some or all of the speakers randomly getting louder and then softer, etc etc
 

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Where is the dealer that installed it? Its their problem.

I would look for ground issues that seems to cause strange feedbacks and such. Not ruling out modules I don't have experience with problems in those. Simply take a DMM and see if any speaker wires (hooked up, just check at amp) are grounded. Unless JL is odd very few amps ground them and will show 1K ohms or something far from zero. If that checks out then take the RCA off and test ground to the shields, those should all show ~0 ohms or close to it depending on the meter and ground you have back there at amps. Also check the amp grounds, or check the voltage at the amp while its turned up and freaking out it should not be dropping way down if you have sufficient electrical. You didn't say if this is a volume dependent issue, but ground loops can get worse above lower volumes. If one amp has a ground loop issue, it can screw up the other amp too.
 

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Discussion Starter #9
What kind of car is it??

I know some of the modules used on newer cars like the new toyota's and dodge's can sometimes have a mind of there own and do the same thing you are describing...Front speakers cutting out, back speakers going crazy, some or all of the speakers randomly getting louder and then softer, etc etc
it's an 2002 mercury cougar



i'm almost positive that it's not a grounding issue. like i said, all new speaker and power/ground wires were properly installed and they're secure.

i also had the battery checked, it's perfectly fine.


the only possible thing i can think at this point is either my Clarion 785DXZ head unit is having some sort of issue with music playback or my front pair of C5s are blown (I don't know how they could have been blown by a low-tuned 300/4)
 

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Discussion Starter #11
honestly i wouldn't think so. the 300/4 i have now just replaced a 300/4 i had a month ago because the old one would overheat after like 30 mins. both were brand new from JL so the odds of having 2 back to back bad amps would be pretty astronomical i would think.

the one i have now doesn't heat up anywhere near as bad as the first.
 

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it's an 2002 mercury cougar



i'm almost positive that it's not a grounding issue. like i said, all new speaker and power/ground wires were properly installed and they're secure.

i also had the battery checked, it's perfectly fine.


the only possible thing i can think at this point is either my Clarion 785DXZ head unit is having some sort of issue with music playback or my front pair of C5s are blown (I don't know how they could have been blown by a low-tuned 300/4)
Does not matter, you have to test it. Thinking its new/right/couldn't be....we all been down that road to nowhere. Test the stuff or swap it out until you find the issue.
 

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Does not matter, you have to test it. Thinking its new/right/couldn't be....we all been down that road to nowhere. Test the stuff or swap it out until you find the issue.
That's really bad advice from you and you normally are much batter than that...You should know as well as anyone just "throwing" part's at a problem until it fixes itself is silly,expensive and it doesnt help ANYONE learn anything
 

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That's really bad advice from you and you normally are much batter than that...You should know as well as anyone just "throwing" part's at a problem until it fixes itself is silly,expensive and it doesnt help ANYONE learn anything
I guess that is why I said the word TEST twice before I said swap? Note that some people don't have a scope and DMMs to test amps like I do, in that case its better for them to swap. Damn, you get what you pay for here anyway what do you want. The point I was making is you can't assume your new titanium coated wires are perfect with the world and don't have a short, you have a problem and you have to find it, in particular if it is stuff you just installed and when the problem showed up. Since JL are pretty good amps, I'll lean towards a wiring issue before the amps, but hard to say not being there and all. I think all the install work I do is perfect too, but its the first thing I check when I have a noise problem like this. You can't assume anything no matter how new or great it is....or infer you don't want to test it because its great or new, which may or may not be the case I don't really care just answering the question.
 

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Was installed at an Authorized Dealer, All speakers and Amp were brand new from JL


My problems :

-Last week my C5s started cutting out completely and coming back on and my back C2s were only playing. It's getting worse. When the C5s cut out the C2s go haywire and increase in volume on their own

-Also, sometimes increasing and decreasing the volume each 'notch' causes a barely noticeable 'pop', even at low volumes.
Hmmm
 

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Sometimes strange things can happen. I wired up quad 12s IB and installed a kicker 700.5. I ran the sub part of that amp on the subs. Didn't have other wiring done yet, so I left the old 2ch amp running the comps in there and didn't use the 4ch part of the kicker. I got weird feedback from the CD player, it made thumps between tracks and other strange sounds, though none were loud, they were in the subs and above the xover frequency. When I swapped comps to the kicker and took the other amp out it stopped. That was an old alpine I'd never had an issue with in maybe 10 installs or more. The sub section is a separate class D amp in the kicker, maybe that had something to do with it.
 

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Discussion Starter #18
maybe i'm just ignorant but maybe the processor in the head unit could cause crazy shit like that?

then again, i drove it today and my C5s stopped playing completely, then the left channel would get loud and stop. i'm starting to think they're blown.

the reason why i think it really shouldn't be wiring is because when i troubleshooted my last bad amp at my dealer, he tested each wire with a DMM and everything down to the tweeter going into the crossovers and it all check out, and this was just a few weeks ago.

i appreciate the input so far from you guys, i hope i get to the bottom of it soon :(
 

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Discussion Starter #19
after 4 months, I've been on my 3rd 300/4 and IT'S STILL doing the random volume peaking on the back speakers. Everytime i get a new 300/4 it will play great for a month then start cutting again until it becomes unbearable

I am absolutely not going to send this thing back for another 300/4. this has been one headache after another.

i thought i would revive my thread just so someone out there can hear my crazy story.
 
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