stupid stereo noise!

#1 08-10-2002, 08:35 PM

Hey guys. I have an aftermarket system consisting of a clarion deck, two jbl amps, and a crossover. Two pairs of RCA's running to the back... when i plug in the Monster Wire RCA's (a lot heavier shielding than my Stinger hyper series), i introduce engine noise into the system. And i do mean engine noise. When the deck is muted, it is so damn loud!!! On an unrelated note, i upgraded to a different amp, so i know it's not the amp that's doing it. My guesses are either the crossover or the RCA's... but this didn't happen in my RX7. There was absolutely no engine noise in the system at all, and i had the same exact components. Is there anything that i could inspect? Perhaps a bad ground somewhere? Where? Should i re-do the grounding for the alternator?

Thanks guys
-Ross

#2 08-10-2002, 10:19 PM

Ground is an important task.. start with the amp ground, then alternator.. some alternator do produce noise also.. Could it be the head unit?

Landshark · #3 08-11-2002, 06:21 AM

your grounds should be as close together as possible. try a ground loop isolator, because its easy to put in (RCA connectors), and if that don't work, maybe try a noise filter on the power lead.

Alan

#4 08-11-2002, 07:06 AM

nope, not the head unit or my equipment. its either the car, or the wiring in the car. It's 4 gauge wiring running on the driver side and two pairs of rcas running on the passenger side.
noise only occurs when the engine is running. I'm thinking its the grounds, so i'll re-do those. The alternator sounds like a valid reason also.

Chris · #5 08-11-2002, 08:23 AM

Get a good quality filter/choke on the power feed for all your audio equipment. The SVX alternator is REALLY noisy! I have seen/heard static inverters that generate less RF noise than my alternator!

Good luck

Earthworm · #6 08-11-2002, 11:21 AM

I'm thinking that it could be the alternator as well. What is your stereo setup?

I noticed interference with my Alpine setup. My alternator died 4 months after install and I don't recall hearing the noise after I had the alternator rebuilt. I'm going to have to take another listen today to be sure.

Fortunately the interference I had wasn't all that bad.

#7 08-11-2002, 11:36 AM

Well... setup is as follows
optima yellow top
4 gauge running to the back through a 4gauge into 4-8 gauge
split from the 4 gauge at the distro block is a lead to a capacitor and a jbl1200.1. Both the cap and jbl1200.1 are grounded at the trunk latch with all of the paint stripped with a grinder.
Off the positive distro block is a 10 gauge running to a JBL 80.4 (used to have a 2 channel alpine, with the same exact results). The 4 channel is grounded at a different location using a 8 gauge wire running to a ground distro block with 10 gauge running to the amp, and another 10 gauge running to the kicker x3i crossover. I had this EXACT setup in my RX7 and no problems.

I'm thinking it's the grounding point where i grounded my distro block for the 4 channel.

As for the rca's... one pair is a stinger hyper series (blue translucent) and the other is monster cables... those are MUCH thicker than the stingers. It gets alot worse with both pairs of the rca's are plugged in. It's not that bad when one of the two is plugged into the crossover. It's a clarion 7575 deck with 4 volt pre-out.

OH YES!! Important fact: when i hit bumps on the road, SOMETIMES the noise diminishes to an almost unnoticable level.

Carrying on.... I think it's the grounding point for my 8 gauge distro block. Perhaps its inadequate ground for the jbl 80.4?

Thanks guys!

#8 08-12-2002, 07:23 PM

Alright... so what i did was replaced the wire from the chassis to the ground distro block with 4 gauge. also changed the wire from the block to the 80.4 with 8 gauge. It sounds AWESOME. There is still a faint hint of engine whine, however... possibly due to the noisy alternator. Any fixes for this?
-Ross
PS: i have some left over 4 gauge, and four 4-gauge ring terminals. Perhaps i should re-ground the battery and engine block?