Help with Static in system?
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Originally Posted by PJK3,Jan 30 2006, 12:50 PM
out of phase wiring won't sound like that, so i'm sorry Avernus, but that's an erroneous guess.
we really need more details.
how are you wired? be specific.
from the head unit (HU) are you using RCA outs or speaker level outs?
at the amps, are you inputing via RCA's or speaker level connections?
what are your gains set at?
does it sound noisey w/ the engine off and the key turned to accessory?
is the noise related to engine or other electronic items (ie fans, power windows, etc.)?
are there any output level control settings in your HU?
and some introductory questions...
do you own and know how to use a multi-meter? can you borrow one or get help?
have you checked your connections at the crossovers?
does it make the noise with the RCA's at the amp disconnected, and the amps on?
we really need more details.
how are you wired? be specific.
from the head unit (HU) are you using RCA outs or speaker level outs?
at the amps, are you inputing via RCA's or speaker level connections?
what are your gains set at?
does it sound noisey w/ the engine off and the key turned to accessory?
is the noise related to engine or other electronic items (ie fans, power windows, etc.)?
are there any output level control settings in your HU?
and some introductory questions...
do you own and know how to use a multi-meter? can you borrow one or get help?
have you checked your connections at the crossovers?
does it make the noise with the RCA's at the amp disconnected, and the amps on?
Amp is given RCA input from HU as input, and Speaker wire (JL) as output to the crossovers. (right now I only have one speaker hooked up to test. Only the Passenger side door has speaker in it for now... will add both once this static is taken care of).
The JL 300/2 I'm not familiar with how to adjust the gains. I set the input sensitivity to half way for the RCA's cuz the HU provides an 8 Volt pre-amp signal.
The static persists through all stages of engine on/off, reving hard, etc. Same static level. The static does not seem to be affected by other electronics in the car. Same static level.
Yes there are output levels on the HU (I set sub out to 0, and bass to 0 [mid way])....
-Yes, I do know how to use and have access to a multi-meter.
-no I have not checked the connections at the crossovers.
-no, the speakers make no noise when the rca's are disconnected.
I have looked into this and I believe there is a short somewhere in the woofer connection/tweeter... I have not run my system since I found this out in fear that I may blow my amp since the output of the amp is shorted. would this be an accurate assumption?? if so, how can I prevent the wires from touching the frame of the door? (other than electrical tape...)
Thank you Everyone for your help!
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Originally Posted by PJK3,Feb 1 2006, 09:29 PM
bah, i was making a nasty comment about how this appears to be yet another "help me with my system" thread that the OP never returns to...
then i realized he only posted 2 days ago...
then i realized he only posted 2 days ago...
but thanks for the "edit" else I'd have to go "NINJA STYLE" on you... HAHAH!... j/k!
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From: Baton Rouge, LA
[QUOTE=EskimoMice,Feb 2 2006, 09:20 AM] I'm wired like the following: RCA from HU to AMP running down the left side of the car. Power wire across engine bay (under windshield wiper area) down the driver side and into trunk.
Amp is given RCA input from HU as input, and Speaker wire (JL) as output to the crossovers. (right now I only have one speaker hooked up to test. Only the Passenger side door has speaker in it for now... will add both once this static is taken care of).
The JL 300/2 I'm not familiar with how to adjust the gains. I set the input sensitivity to half way for the RCA's cuz the HU provides an 8 Volt pre-amp signal.
The static persists through all stages of engine on/off, reving hard, etc. Same static level. The static does not seem to be affected by other electronics in the car. Same static level.
Yes there are output levels on the HU (I set sub out to 0, and bass to 0 [mid way])....
-Yes, I do know how to use and have access to a multi-meter.
-no I have not checked the connections at the crossovers.
-no, the speakers make no noise when the rca's are disconnected.
I have looked into this and I believe there is a short somewhere in the woofer connection/tweeter... I have not run my system since I found this out in fear that I may blow my amp since the output of the amp is shorted.
Amp is given RCA input from HU as input, and Speaker wire (JL) as output to the crossovers. (right now I only have one speaker hooked up to test. Only the Passenger side door has speaker in it for now... will add both once this static is taken care of).
The JL 300/2 I'm not familiar with how to adjust the gains. I set the input sensitivity to half way for the RCA's cuz the HU provides an 8 Volt pre-amp signal.
The static persists through all stages of engine on/off, reving hard, etc. Same static level. The static does not seem to be affected by other electronics in the car. Same static level.
Yes there are output levels on the HU (I set sub out to 0, and bass to 0 [mid way])....
-Yes, I do know how to use and have access to a multi-meter.
-no I have not checked the connections at the crossovers.
-no, the speakers make no noise when the rca's are disconnected.
I have looked into this and I believe there is a short somewhere in the woofer connection/tweeter... I have not run my system since I found this out in fear that I may blow my amp since the output of the amp is shorted.
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thanks! PJK3...
I did what you said... and I found that the AMP had a bad right channel. I connected the driver side door speaker to the right channel and got the same static. I have temporarily put both speakers in parallel to the left channel only. (running mono...
)
Do you guys know of any places that might be able to fix a amp that has a messed up right channel? thanks for you help guys!
I did what you said... and I found that the AMP had a bad right channel. I connected the driver side door speaker to the right channel and got the same static. I have temporarily put both speakers in parallel to the left channel only. (running mono...
)Do you guys know of any places that might be able to fix a amp that has a messed up right channel? thanks for you help guys!
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From: Baton Rouge, LA
be cautious -- iirc, the JL / series amps are only 3 ohm mono stable.
regarding getting the amp fixed, i generally try to see who the local dealer recommends. if it's under warranty (by your question, i'm guessing it isn't), i'd ship it back to JL. since it probably isn't, i'd check on JL's site or call them and see who the authorized repair center nearest you is... my personal experience has been that it costs around $100 to get most amp problems fixed.
regarding getting the amp fixed, i generally try to see who the local dealer recommends. if it's under warranty (by your question, i'm guessing it isn't), i'd ship it back to JL. since it probably isn't, i'd check on JL's site or call them and see who the authorized repair center nearest you is... my personal experience has been that it costs around $100 to get most amp problems fixed.
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Originally Posted by PJK3,Feb 6 2006, 10:18 AM
be cautious -- iirc, the JL / series amps are only 3 ohm mono stable.
regarding getting the amp fixed, i generally try to see who the local dealer recommends. if it's under warranty (by your question, i'm guessing it isn't), i'd ship it back to JL. since it probably isn't, i'd check on JL's site or call them and see who the authorized repair center nearest you is... my personal experience has been that it costs around $100 to get most amp problems fixed.
regarding getting the amp fixed, i generally try to see who the local dealer recommends. if it's under warranty (by your question, i'm guessing it isn't), i'd ship it back to JL. since it probably isn't, i'd check on JL's site or call them and see who the authorized repair center nearest you is... my personal experience has been that it costs around $100 to get most amp problems fixed.
I will call around and see who is authorized to fix the right channel of the amp.
also, does anyone know why a light hiss might be caused by in the speakers? is it due to the HU being not grounded? (I have no grounded the HU). If this is the cause, how do I go about grounding it (I didn't see a ground wire)?? the hiss is very light... so I'm guessing it maybe due to the grounding issue on the HU trying to ground via the RCA to the amp's ground? can someone confirm this? thanks!
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From: Baton Rouge, LA
yes -- YOU MUST GROUND THE HU! that would account for most of it (which honestly, i think i predicted. )
and as John mentioned it would be the black wire on the HU harness. at a minimum, solder or splice it to the OEM ground or preferably ground it on a solid unpainted bolt nearby.
JL amps are 1.5 ohms stable -- in stereo. just about any amp when bridged mono is stable at double the stereo number. so 1.5 ohm stable in stereo = 3 ohm stable in mono. if you take two 4 ohm speakers and put them in parallel - that's 2 ohms, which won't be stable in mono on the JL. don't worry, i doubt you did damage, and it's a VERY common misconception.
from the JL website: http://mobile.jlaudio.com/products_amps.php?amp_id=253
[QUOTE]
300/2 Class A/B Two-Channel Full-Range Amplifier Specifications:
)
-since the speakers make no noise when the RCA's are disconnected, that means that your amp to speaker chain is not likely the problem.
*make sure your HU has a GOOD ground. double check it. if you're tied into the factory harness, make sure the connection is solid. if it's solid, consider relocating to chassis. if you're already on the chassis, make sure it's solid, and consider cleaning paint away to get good contact.
(often a hum like this is a ground loop hum. which would indicate that your HU is trying to ground itself through the amps (and RCA's), which is why you'd get a hum.) i would pursue this first.
*make sure your HU has a GOOD ground. double check it. if you're tied into the factory harness, make sure the connection is solid. if it's solid, consider relocating to chassis. if you're already on the chassis, make sure it's solid, and consider cleaning paint away to get good contact.
(often a hum like this is a ground loop hum. which would indicate that your HU is trying to ground itself through the amps (and RCA's), which is why you'd get a hum.) i would pursue this first.
JL amps are 1.5 ohms stable -- in stereo. just about any amp when bridged mono is stable at double the stereo number. so 1.5 ohm stable in stereo = 3 ohm stable in mono. if you take two 4 ohm speakers and put them in parallel - that's 2 ohms, which won't be stable in mono on the JL. don't worry, i doubt you did damage, and it's a VERY common misconception.
from the JL website: http://mobile.jlaudio.com/products_amps.php?amp_id=253
[QUOTE]
300/2 Class A/B Two-Channel Full-Range Amplifier Specifications:
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Originally Posted by darkknight1999,Feb 8 2006, 04:22 PM
You didn't ground the HU? 
On the harness is the black wire for the ground... where did you put it?
On the harness is the black wire for the ground... where did you put it?