I recently installed a system in my TL it consists of:

1:RCA connectors soldered to head unit outputs (front left, right and Sub)

2:Power is ran down driver side, RCAs on passenger.

3:Mounted in the trunk is an Audiocontrol EQS and a PDX F6 (chan 1+2 to the fronts and 3+4 bridged to the sub). I am using only the front and the sub inputs on the EQS.

Problem is i can hear buzzing/static out of my front tweeters, i can not hear any kind of hum out of the sub. The buzzing is quite low level but increases if i increase my input gain on the EQS (seems pretty obvious it is coming from before that point)

What i have tried:

Changing EQS jumpers to unbalanced --> Made issue much worse
Changing EQS ground jumper to isolated> 200 ohm> and Ground Did not have any impact on noise. (left on isolated)

Cleaned paint off factory ground point under hood from battery

Amp and EQS are grounded to factory Ground point in passenger side trunk.

Noise is gone if i disconnect soldered RCA's near oem amp.

Noise is increased if the Ground of the RCA's touches the oem amp.

If anyone has any suggestions of what to check next i am all ears.

Do i need a ground loop isolator ?

 

I see soooo many people on these forums say they use a factory ground point. You should never use a shared ground point when grounding stereo equipment. Its one of the major ways to induce engine noise in to a system.

 

Thanks for the reply, i did not know that. People seem to suggest mounting to a factory location. I can quite easily drill a hole and use a nut and bolt somewhere further down the sheet metal. I will try that and see it it makes a difference.

 

It may not have any effect as I have seen alot of people on here having issues with using the cut RCA's wired to the head unit output method. If you are using a decent set of RCA's they should have a wire that you can ground to help reduce noise. There will be alot of people that will say they aren't worth the money but I have found Monster Cable 400 series RCA's to be some of the best to help reduce noise. I would never pay full price for them and I haven't. Dealer cost on almost all monster cable stuff is more then half the MSRP.

 

It did not have any effect unfortunately. I am not using great RCA's by any means, they are some lower end monster cables. I do not think that the cables are picking up noise though as i should still hear it when i disconnect the rca's at the factory amp. The noise goes away then.

 

I think you might be right, I just ran another set of RCA's i have on the outside of the car and the noise was gone. The ones i bought are probably just shitty.

 

Yeah good priced RCA's are a must have for any upgraded sound system IMO. They run a good distance in the car and can pick up alot of noise if not properly shielded.

 

Happy that solved your issue. Good RCA's are very important to a good sound system. Alot of people overlook spending money on them. I have been a mobile electronics installer for over a decade and seen people spend thousands on a system and spend $20 for RCA's and then they wonder why it sounds like shit.

 

Any recommendations besides the monster ?

 

Depends on how much your willing to spend.

 

I am open to anything, as much as i need to, to get a good quality noise free cable :p if i can find a 4 chan for under 100 i would be happy.

 

What length do you prefer. I suggest going with about exactly the length thats needed. Too long of RCA's usually means bundling them some place which also induces noise.

 

There is actually a bunch of other good companies besides Monster. I'd suggest Streetwires, Stinger and even Tsunami. Check this site for ideas: http://www.sonicelectronix.com/viewc...der=price_desc

 

Check out Monoprice's RCA's...


www.monoprice.com

 

The first thing you should know is that the TL's HU output is a balanced signal. Also some unbalanced/single ended/RCA cables float the shield; these cables are not suitable for carrying balanced signals.

Do you have a multi-meter? If you do, check the continuity of the cables you were using. You might find that there is an open somewhere. Balanced signals are quite immune to noise pickup. If your cables have continuity it is unlikely that you will pickup noise from the car. Make sure that the AQ EQS is configured for balanced inputs.

Any well made cables will work for you.

Good Luck

 

I thought that they were balanced out of the head unit. I configured the EQS for balanced. If set to unbalanced the noise is crazy. I think it is just that the cables are crappy. They are monster 101 i think, the ends are loose as well. I ordered some twisted pr ones from Knu to try.

 

JL audio was having a deal on their webstore for some of their twisted pair RCA cables. Like half off or more. Might check that out. It was considerably less than the usual price around the web for them.

 

I'm dealing with the same problem man. I'm going to try to wire up the speakers "post-amp" today and see if that helps. Maybe it's just an issue with the level being so low. My subs wired pre-amp with my pdx on .1-.8v and gain damn near all the way doesn't sound good at all. Not sure why...but I guess I'll be using the post-amp for both.

..Now that I look at your OP...I wonder if it's a problem with the PDX's?? I got 0 start-up crackling/hissing with the PPI art through a ground loop...but when the PDX was swapped it started getting nasty sounding upon start up. PPI still made noise with ground loop out of the equation though. Hopefully I can get mine figured out soon as I'm going insane I think


Edit: just realized I passed 1,000 post

 

It may be an issue with the old PDX, the noise floor on this new one seems to be dead silent, When i ran a new rca on the outside of the car it was perfectly clean. That leads me to believe that it is an issue with the ones i installed. I am with you, any noise drives me crazy!

 

So you ran RCA's outside of the car and it sounded clean? I know the older (mine) have noise floor issue's but I don't think it should be making a crackling sound upon start up and when the volume is on 0. Its not just a hiss which is driving me nuts also

I've got Fosgate RCA's for my subs and they sound fine (could just be b/c the noise gets LP'd out). I bought some Radioshack twisted RCA's for the component amp and that's what's giving me a hard time. I figured they were shit so I had a Monster RCA cable laying around. Used it...same damn noise. Maybe I'll run it outside the car like you did...though that shouldn't have any effect. Hell...even if it did work, I dont want to have my RCA's dangling outside the car while I drive haha

 

I have no start up noise, no crackling just a constant low level buzzing when the car is running. When i plugged in a different set of rcas for testing they were perfectly quiet outside the car.(I do not drive around like this) Currently i think i am not using twisted pr ones which might be the problem. I do not have any noise on my sub either using the same RCA's.

 

Well I hope you get yours all fixed up too!! I was about to switch my component wiring to post-amp but I just downloaded the PDX4.100 manual and it says the Input Sensitivity is 0.2-4V (this is fixed too..no swtich like the PDX1.1000). So I'm a little unsure if I should wire it up now seeing how the post amp signal is much higher than 4V if I remember correctly. Closer to 8V I thought...

 

Is it possible that you guys are getting noise from the area where you connected the RCA's to the head unit wires by the amp? How did you cover up the connection?

On the twisted pair how did you know which one was the positive, negative, right and left? Assuming they run in the same shield.

 

What do you mean where we connected to the head unit by the amp??

For RCA's, I just cut off the terminal and dissect it lol. Outside is neg. and middle is pos.

 

In the bundle of wires they are very easy to find and are color coded. As far as polarity that is listed somewhere on the site.

There is a chance you can pick up noise there though, I used high quality all metal solder on RCA ends and when they touched the stock amp they grounded against the casing. This was easy to fix as I put some large shrink tube over the outside of the RCA.

 

I meant on the RCA cables. When you cut them and if they are twisted there would be 4 wires running thru the casing for Left +- and Right +-. On untwisted you would just take the center as + and outer as -...how do you know if they are twisted?


Thanks

 

I did not cut any rca cables, I soldered only ends onto my stock wiring and used barrel connectors . If you had decent cables you could still tell by unscrewing the end and looking at what was connected to the outside and the center pin. Outside is the - and pin is the +

 

I cut the ends of my RCA's off on one side and looked to see which was the outer/ground (-) wire and then wired them into the pre-amp wires. I've got electrical tape around them at the moment as I didn't want to do anything semi-permanent while trying to tackle the noise

 

Just wanted to post, got my new krystal kable interconnects in from knu koncepts today and after installing it am completely noise free. So much happier now. I still plan on doing the big three in the near future though.

 

Pics of setup?? What exactly do you mean by "interconnects"? I'd just like to see how you set everything up...

 

RCA's

http://www.knukonceptz.com/productMa...20RCA%20Kables

I have some of their products and they're pretty nice.

 

Very nice!

 

What kind of pictures ? There isn't a lot you can see because i put shrink tube around the rca ends by the factory amp.

Set up is as follows.

Male RCA ends soldered onto outputs of stock deck pre amplifier. Something like this
Those go into barrel connectors, so the male ends of the interconnects can be connected.

In the trunk the Interconnects connect to a audiocontrol EQS, and then from that to the Alpine PDX.

If you are looking for a specific picture let me know.