JBL MS-8 help

[Volvo_S80]

Ok I've had the system installed for a little while and there was alot of noise and after some re-grounding most of the noises went away there was a faint kind of high pitched noise maybe "airplane noise"? that I just accepted at the time because I had made it so much quieter it seemed like nothing..... Until now

While going through the checklist of ground loop issues I decided to just eliminate both my sub amp and my High/mid amp and go straight from the MS-8 and I still have the noise. So the current setup is Signal from my Factory Amp (front left and right speakers) to the MS-8 and I'm now using the MS-8 internal amp to my front tweeter and mids 4 channels total. Still have the noise. The mic is not connected and i tried to disconnect the display as well to see if it helped and it didn't. I had the remote turn off set to 5 seconds and that noise stays for the 5 seconds after the display turns off until it completely shuts down. I made a new ground just for fun. Maybe I'm missing something? Bad MS-8?

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[fly_marlin]

Ok I've had the system installed for a little while and there was alot of noise and after some re-grounding most of the noises went away there was a faint kind of high pitched noise maybe "airplane noise"? that I just accepted at the time because I had made it so much quieter it seemed like nothing..... Until now
While going through the checklist of ground loop issues I decided to just eliminate both my sub amp and my High/mid amp and go straight from the MS-8 and I still have the noise. So the current setup is Signal from my Factory Amp (front left and right speakers) to the MS-8 and I'm now using the MS-8 internal amp to my front tweeter and mids 4 channels total. Still have the noise. The mic is not connected and i tried to disconnect the display as well to see if it helped and it didn't. I had the remote turn off set to 5 seconds and that noise stays for the 5 seconds after the display turns off until it completely shuts down. I made a new ground just for fun. Maybe I'm missing something? Bad MS-8?

Can you clarify what "While going through the checklist of ground loop issues I decided to just eliminate both my sub amp and my High/mid amp and go straight from the MS-8" means exactly? I'm a little confused.

 

[Volvo_S80]

In order to access my rca cables and ground wires I have to pretty much tear everything out so I started with taking the Sub amp out of the equation so see if that made a difference. It didn't. So I just took out the sub amp because it's easier to access my High/Mid amp. Then I took the RCA's out from the Highs amp and the noise went away. But in my head that's because they aren't getting a signal so why would it make a noise. Now in the back of my head I can hear everyone from the forum saying it's probably your grounds. So i decided to take my amps totally out of the equation and use my sub amp ground on the MS-8 because IMO it's the best one. So basically I was making sure it was't a ground issue. I had the MS-8 and my Zed sharing a ground and The DD M2C has its own ground next to the muffler bracket bolt under the car. I had to separate them on the original install to get rid of alternator whine

 

[fly_marlin]

In order to access my rca cables and ground wires I have to pretty much tear everything out so I started with taking the Sub amp out of the equation so see if that made a difference. It didn't. So I just took out the sub amp because it's easier to access my High/Mid amp. Then I took the RCA's out from the Highs amp and the noise went away. But in my head that's because they aren't getting a signal so why would it make a noise. Now in the back of my head I can hear everyone from the forum saying it's probably your grounds. So i decided to take my amps totally out of the equation and use my sub amp ground on the MS-8 because IMO it's the best one. So basically I was making sure it was't a ground issue. I had the MS-8 and my Zed sharing a ground and The DD M2C has its own ground next to the muffler bracket bolt under the car. I had to separate them on the original install to get rid of alternator whine

Separate the grounds for the ms-8 and the Zed. Can you elaborate on your sentence about taking the RCAs out of the Zed and noise going away, but it doesn't matter because it's not getting a signal?

 

[Volvo_S80]

In my head if I take out the RCA cables my speakers wouldn't make any noise at all. Because there would be no signal going to the speakers. Unless maybe there was a ground issue then you would hear something. That's just what I've gathered looking up info. So when I took the RCA's off of the zed there was no noise. But how could there be noise with no signal.

I think I found something! So I disconnected the speakers one by one until I figured out that there is 0 noise when I disconnect both tweeters. The noise is there with just the left or just the right hooked up. I'm searching that now

 

[Volvo_S80]

My stock Tweeters came with caps should I try to throw those on and see? Can I hurt my current tweeters if I do?

 

[fly_marlin]

My stock Tweeters came with caps should I try to throw those on and see? Can I hurt my current tweeters if I do?

You're running active off the zed, right? If you have a coaxial-to-RCA adapter, you can connect the amp directly to your phone. If noise is still there, that will eliminate the RCAs as the possible cause. I don't think the tweeters themselves are the issue. Do separate grounds for everything to start off.

 

[trumpet 5,000+ posts]

My stock Tweeters came with caps should I try to throw those on and see?

yes

 

[Volvo_S80]

You're running active off the zed, right? If you have a coaxial-to-RCA adapter, you can connect the amp directly to your phone. If noise is still there, that will eliminate the RCAs as the possible cause. I don't think the tweeters themselves are the issue. Do separate grounds for everything to start off.

No the MS-8 does the crossover automatically. I don't have a coaxial to rca unfortunately but when I took the zed amp out of the picture and ran my speakers off of the MS-8's internal amp I wasn't using any RCA cables and still had noise so it should't be RCA's. The RCA's run from the MS-8 to the zed and they are only 6 inches away from each other but I bought Krystal Kables From Knu before i knew exactly what i wanted to do so the rca's are 16 ft. long coiled up because i only needed like 6 inches but they are away from the power.

I have 2 long runs of wire 2 pairs coming from the factory amp located under the passengers seat. These are my inputs to the MS-8 in the trunk (16 gauge NVX)

The other runs are 2 pairs of NVX to each side of my front speakers. 1 16 gauge 1 12 gauge each side.

Then the power's I ran 2 1/0 (Sky High) from battery to trunk I was conscious about keeping them away from my speaker wires.

The MS-8 Zed and DD are all in the trunk stacked on top of each other. I have 6 RCA's coming out of the MS-8 to the amps 4 to the Zed 2 to the DD. But like I said unfortunately the 4 channel RCA's are 16 ft long just coiled up same with the 2 channel RCA's and Id say at least 8 inches away from any power source.

As for the caps I'm going to need a friends help they are very small and I'm going to have to solder them

*edit I did try the cap on one tweeter and still the noise is there.

I hooked everything back up Different grounds for everything this time also. The noise is louder now than it was with just the MS-8 I have the gains set right in the middle at 1.4 and now that its louder I can hear it in my 6.5's as well

 

[trumpet 5,000+ posts]

If you have to bundle up long RCAs it's best to have them straight and folding back over a few times. A stack of loops makes them more prone to picking up EMF which can lead to noise like you're hearing.

 

[Volvo_S80]

I do have them in a loop now I will try that out next. Actually I'll just lay them out over my seats and see if I can hear it. I've been wanting to order shorter ones but I already spent enough on the ones I have :/

I played with the gain and if i turn it way up it gets louder but from 1.4 down to 8 the lowest for me it stays the same. but it is coming from all speakers now. Changing the balance from left to right does nothing But it does go away when I mute the MS-8 with the remote

 

[Volvo_S80]

I hooked just the speakers up to just the MS-8 and I still had the noise

Just realized that. I did get louder once I hooked it all back up but it was there even just with the MS-8

 

[fly_marlin]

Did you get the ms-8 its own ground yet?

 

[Volvo_S80]

Did you get the ms-8 its own ground yet?

Yep Everything is grounded separately and I made them all a bit shorter in the process nothing is over 12 inches

 

[fly_marlin]

Does sound like something in the ms-8 is the culprit. Call JBL and see if they can tell you anything?