noise problems

neomagus00

story time first:
yeah, so i decided to mess with my stuff again. ive got the mm6 comps. i had the tweets in the dash and the mids in the door; i wanted to see how it would sound with the tweets next to the mids. so, i take a couple panels off, moved the tweets, temporarily mounted them in the right spot, and i liked it better. fine.

so i go to stick them there permanently, and find that there's no way to get the wiring for the tweets in to the doors - there's only one pair available. i didn't consider drilling a new hole, cause i thot this would work: just stick the xover in the door. i did weatherproof it, using an ingenious combination of tupperware and hot glue (i stuck the assembly in the bathtub overnight, no leaks!). so, the setup is: channel from amp, through door connection, to xover, to mid and tweet. i do both doors, then hook up the rest of the amp and turn it on to test... and a sound like a cat being tortured screamed out of the setup. naturally, i turned it off asap, then began searching for the problem.

i didnt find one! i backed it all the way down to bare-bones: one mid hooked up to one channel of the amp, and while there's no more screaming tortured cat, there's a significant amount of noise that was def. not there before, with these characteristics: the noise level doesn't change with hu volume or source (tuner, cd, sirius). it does get worse and acquire alt whine rather badly when the engine's on. the ground is the same one that i had before, same with power and signal and turn-on cables. i even moved the power and signal cables around to try to remove noise - nothing.

it's not the hu - my stock rear speakers work just fine. it can't be my wires - they're the same as before.

any idea what's goin on? could i have accidentally hurt the amp somehow (i still don't know how it happened)? any troubleshooting steps to rid myself of the noise?

exalted512

tupperware...thats awesome, this isnt the problem, but the crossover has to have room to cool...keep that in mind
have you taken the crossover out and put it back where it was?
i would start from the beginning even though its going to be a major PITA
just take out the crossover, go ahead and leave the speakers there, but disconnect the speaker wire from the amp, from the crossover, and from the speakers
do you have any speaker at all laying around, even like a HT speaker or one off a shelf system that has regular speaker wire coming from it?
if so, hook it up directly to the amp(making sure the volume is down) right beside the amp
if it works fine then its not the amp
from there, hook the speaker wire back up to the amp and run it straight to your mid(make sure the mid is where its going to be installed)
make sure your volume isnt loud or anything and it will not hurt your speaker
if it seems to be working fine then its not your speaker wire
if thats ok, hook it up to the speaker wire to the crossover then the crossover to the mid
do this all without mounting anything
if it works, hook up the tweeter
if theyre working fine, then its not your crossover
next thing is putting the crossover back
if it starts making noise then, its probably that the location of the crossover and you might have to move it back:(
hopefully youll find your problem
i cant think of any problem that will be more likely than something else so id just start at the beginning which is your amp
if you hook up the first speaker right next to the amp and the speaker is making funny noises, then youre going to have to start working backwards from the amp, checking power, ground, rcas and if none of that stuff works, youll probably need a new amp...
-Cody

neomagus00

okay, i backed it all the way down to a different HT speaker hooked to the amp with a 12" piece of wire; that is, the speaker was sitting right next to the amp, and there was still noise.

so, i went for the input side:
ground: i couldn't undo the bolt that has the ground cable under it - i didn't have a long enough wrench - but i'm gonna assume that it's good, cause it worked fine before.
power: it's the same too; no cuts or kinks or anything screwy.
rca's: again, same thing, i ran them as straight as possible (right over my seats) and still noise
remote lead: just in case, but it's good too.

so, i took apart the entire front of my car to find the ground cable for my hu, just in case... haven't found it yet, but i will.

took the cover off the amp just cause, and after a thorough visual inspection, it seems just fine. called polk, they said to take it to a shop, but i don't have the cash to get them to troubleshoot. well, i didnt ask if theyd charge beforehand, but i assume they do.

i just don't know where to go from here...

btw, this is what my car looks like now; note the lack of a ventilation system, glove box, and every single panel in the car except the center console, and that's only cause the key goes there so it's locked down really well.

exalted512

do you have a friend with an amp that you could switch out real quick?
probably wouldnt take 20 minutes since you can just hold the amp there...
-Cody

neomagus00

i thought of that, but everyone i know that has an amp is unavailable ATM. oh, here's that pik:

MacLeod

This sounds very familiar! About 5 years ago I was driving down the road and this horrible sound came thru the speakers! It scared the hell out of me!! I thought some kind of creature had stowed away in my truck and was about to eat me!

Well I turned everything off and spent the next day looking over everything. Speakers worked fine off the HU speaker leads, everything was securely mounted and worked fine. Power, ground, everything. So I said to hell with it and started pulling out all the wires.

Luckily I hit it on the first wire. As I pulled out the ground wire I discovered a stripped patch about 1/8" long. Apparantly this was arcing on something under the carpet. The place where the stipping was would put it somewhere under the drivers seat. Even tho my amps were behind the seat ('00 Ram reg cab) I ran my ground to the front right drivers seat bolt so I ran it under the carpet to there. I cant remember why I did it that way but moving right along, I guess that I mustve pulled on the wire or sat something down on it or whatever the hell and it pulled enough coating off to expose the wire.

Well I went and bought a brand new wire and ran it from scratch. Never had a problem again.

The moral of the story? Just because a connection is solid at both ends and appears to be functioning doesnt mean there is nothing wrong with it in the areas you cant see.

I would start with the ground wire. The alternator whine kind of makes me think it may be there.

APSkill187

Yeah I would def say its the ground arching on the frame of the car in which its running in. If that fails you I remember a while back when mine did the same thing. I Just twisted the wire running from the crossover too the tweet. And Simply covered them with a piece of lead or aluminum foil it helps significantly. Other then that i dont know what it could be. But Good luck

mbdyer12

I have a bit of that alternator whine still myself. I've checked and rechecked the ground. I've sanded the area around it for a good 3 mins straight to make sure i was making a good connection and screwed it down with washers too. I'm only getting the noise out of 2 of the channels though. I switched the pairs to make sure it wasn't the speaker cable itself. Although the RCA cables are going through the same spot, could only 2 of them pick up interference or could it be that the set of cables are bad? I've only got 12 ft of rca cable to work with so running it is kinda tough. I've got 4 guage running down the driver side, so I probably shouldn't run it there... the only other option is run it straight under the carpet and under the back seats. Ahhhh its frustrating. I almost wanna just take it to a shop and tell them "fix it for me."

exalted512

Originally posted by mbdyer12
I almost wanna just take it to a shop and tell them "fix it for me."

I have that feeling a lot...lol
and yeah, it can be the RCAs even though they are close, but doesnt mean its bad
neo, do you have any power wire left over where you can hook it to the amp and ground it somewhere else?
-Cody

neomagus00

yeah, then they charge you out the arse to fix something you'll slap yourself later for not thinking of

okay, i'll doublecheck all my wiring tomorrow. i'll go beg a friend for a big enough wrench to deal with the ground wire and re-grind that area. and, if that doesn't fix it, ill probably get better wiring and see if that does it.

mac - that's exactly the kind of noise i had, so i'll make real sure to do the ground properly.

exalted512

oo, and btw the pic is awesome...lol
you shouldve seen my truck when i was rewiring everything
i started one weekend and didnt finish and i had to wait til next weekend
the dash was still intact but EVERY other panel was out, the carpet was out, the driver seat was the only seat in the truck, and the only seat belt...i had to ducttape the sensors that know when my door is open so i wouldnt drain my battery
crazy stuff
-Cody

neomagus00

man, i wish i could take out the carpet... it would make stuff so much easier, but it's one giant formed piece that goes under the seats and such.

thankfully, i haven't had to do anything like the door sensor thing, but this deal has been for over a week now, working on it pretty much every spare moment... this car's pretty slow-going...

exalted512

to take out the carpet i have to take out the plastic where you step to get in, and unbolt the front seats
but yeah...its one fatty piece as well
-Cody

neomagus00

id be worried about undoing my seats... motorized and heated, so who knows how much wiring they've got under there...

exalted512

my seats take motor skills to operate while driving...does that count?
usually its just a connection or two to unplug...no biggy
-Cody

neomagus00

okay, i gave in today and took it to my shop. in five minutes, they'd diagnosed it as a bad noise filter in my hu, and pronounced it a dead man walking; they said that problems cascade from here on in, and that i should get a new hu.

so, has anyone heard of this happening? if so, is the hu shot or can i fix it? they said that eXcelons are known to do this...

i had a guy be a salesman for a while, and i think that if i do end up getting a new hu, it'll be eclipse's top end cd HU... the CD8454 . i really really like this... i kinda hope i have to get it! is it a good choice? are there better choices?

exalted512

pioneer premier p-9:)
-Cody

neomagus00

yeah, that's like twice the price of the eclipse... the eclipse is $550, and pioneer's equivalent offering is...the 860mp. from specs, the two seem very much alike. i still like the eclipse. i can get the p8mp for $450, but it's significantly less capable than the eclipse imo, esp. the preouts bit... eclipse: 8V@55 ohm, pioneer 6.5 @100ohm. the pioneer up from this is also 6.5.

and lucky me, the 300.2 takes 8V .

so, original question... is it necessary to replace the hu? then again, now that i have the idea, id probably do it no matter the answer .

and are there better choices at the same price level? (~$550)

exalted512

my deh-p940 was $550 at www.electronicscity.com
-Cody

neomagus00

that model's not there anymore, but those with close model numbers are ~$400. strangely, i can't find the eclipse anywhere... the closest i've found is a few lower-end units on acaraudio.

MacLeod

My personal favorite. This Alpine has a very flexible crossover, 3 sets of 4 volt preouts and time correction. $550

This Clarion at $500 isnt bad either.

exalted512

eclipse has no online authorized dealers, maybe thats why:)
-Cody

neomagus00

yes, that could do it.

okay, i'm making a new thread on this so others can throw in opinions, so the rest of this post is there.

MTXMAN

i saw that pic and said to myself "yep, been there" lol


I actually just got rid of my alt whine and a power cut off problem by replacing my remote wire, it had one small section that had been barely cut into but it was enough to cause problems...but now, problem solved for hardly any money YAY