So i've looked into this alot on here and though i haven't tried everything thats been suggested yet I was hoping i'd get more answers for my situation from you guys out there.... yes i searched... alot but i need more help. thanks in advance

I have tried finding out what the sound is coming from and haven't been able to get rid of it as of yet. I have disconnected the RCA's from my headunit to see if the sound goes away but its still there... i'm pretty sure its coming from my amp but i moved the ground a few times so i dunno.

my rcas run down the drivers side of my car and the speaker wires down the passenger side. the hum is from all 4 speakers so it has to be the amp correct? its a brand new alpine pdx4.100 so i dunno what the issue is ... any help is greatly appreciated.

afternoon bump^^^

 

Hey man!


Altinator whine is the pits. I can help you get to teh bottom of it. Just need more info.

Is your HU powering the speakers, or the amp? Is there a sub? What gauge wire is hooked to the amp? How long is your ground? Do your RCA's have a "sheild ground"?

First step anyway, unplug the RCA's at your amp. If you start you rcar and still get alt whine you KNOW 100% it is your amp. If you install is correct, then your amp is defective. Also if you unplug the RCA's and turn on your car, plug in (when powered down) and I-pod or something to the amp and see if you get whine while using a source unrelated to the car.

Good luck.

 

if you unplug the RCAs you should get no sound.

Try grounding the chassis of the HU to the rca shield

 

My amp powers the sub and another amp powers the speakers.... i believe i only get whine in the speakers and not the sub.

Tomorrow im going to try either grounding the HU to the rca shield or move my ground. I am really hoping it is not my amp because well i just bought it and that would really tick me off so it better not be the amp. hopefully tomorrow i can figure it out... thanks guys

and emp... if i do unplug my rca's and stillg et sound... what do i do next?

 

so you unplug the RCAs from your midrange speaker amp and you still get whine? from where? what does it sound like?

you may be getting transformer noise... then again i havent opened one of those pdx's up so i dont know wft is in there

 

yeah a few weeks ago i opened up my dash and played around and i was pretty sure i pulled all the rcas out and the sound still came through the speakers. i may have to pull all my speaker wires out or make a test speaker with one of the old crappy stock speakers to see if its my speaker wires picking up noise.

the pdx is crazy inside... i opened it up to see if everything was ok and man a ton of small parts. makes you appreciate electronics haha

 

lol ya most are cramped nowadays. The speakers should be hooked up direct from the amp meaning by unplugging the RCAs and loosing signal to the amp it should go quiet. Speaker wires cant pick up whine or noise in anyway shape or form. Who hooked the amp up? and what speakers do you have?

 

I have alpine type R's all the way around (6.5 comps up front and 6x9s in the back) and i did myself with the help of my car audio guy at visions. there shouldn't be anything wrong with the install... i have 4 guage from battery to a 60A fuse and then 4 gauge to the amp.

 

did you connect any of the stock speaker wires behind the deck?

so when you disconnect the rcas you get no music from the speakers correct. but you still hear whine?

 

hmm come to think of it i may have left 2 of the stock wires attached to the HU wiring harness... think that is the problem?

and yeah the signal goes away but the whine is still there i believe. i will for sure know tomorrow cuz i am fixing this problem! i cant stand hearing that sound haha

 

just like i thought... i bet your stock tweeters are ******* this **** up.

 

ahhh well i sure hope thats it! that'll be the first thing i do. I was thinking about this earlier so hopefully that will fix the problem. If so that'll legitimately make my day haha!

where is the best ground for my amps btw?

 

best ground is the battery neg. otherwise a sanded down piece of metal without a gas tank or something else under it

 

Ground loops can be a pain but it sounds like you're off on the right troubleshooting steps. If you disconnect the RCA cables from the amp and still get noise I'd also look at your wiring for the positive power feed in addition to the ground source/length and make sure the speaker wires coming off the amp aren't running near anything that could pick up noise but that usually isn't the primary cause, especially if you're getting it from all the speakers. Alpine still makes some nice products but if you try to rule out everything (mounting, wiring/power/grounds, etc.) and are still getting whine or noise I'd say there is a chance something could be wrong with the amp but in my experience it's usually something with the installation. Just out of curiosity, does it change in intensity if you change the gain on the amp or play with the hi/low-pass filters (assuming that model should have some implementation)? Also you mentioned this is a multi-amped system. Are you running a distribution block for the grounds on both amps?

 

Ok perfect thats where i had them... i changed it around but wasn't sure if that would be the best. thanks emp

yeah i dunno im looming everything tomorrow so it'll all be seperated soon. and i just figured out today to play with the gain so i have yet to do that... will let you know tomorrow. and as for a dist block... no i dont have one. what are the benefits of this? god i hate not knowing things haha. thanks in advance

 

Using a power distribution block to run one single larger diameter wire (i.e. smaller gauge number) from a remote battery location (normally up front in most other cars) to where your amps are located (normally in the trunk area) and then split off from the block to each amp or device that needs power isn't usually a problem, but if you have only one ground location for your amps, the wire isn't grounded very well, then you try to use that one ground to go through a distribution block then split off to each amp it could potentially cause issues. You want to keep the ground wire runs as short as possible and the same size as your power wires. Since the battery is pretty easy to get to you might try attaching your ground(s) directly off the battery temporarily as suggested to see if there's any change. And make sure your gain isn't turned all the way up (1/3 to mid way is usually a good starting point) since some lower-end and mid-range amps may put out a lot of noise even with no input source.

 

hmmm thanks i'll take that into account... greatly appreciated. I'm workin on the car tomorrow (day off thank god haha) and i'll let you guys know how things went or whatnot

hope i can figure it out cuz it ruins a system ya know! anyways im out for the night i think haha later guys

 

never herd an amp give out any noise thru the speakers without a input source.

 

Bah this is effed then... i'll figure it out tomorrow and if i dont figure it out... imma cry and probs just get smashed haha

 

lol i may have a use for a broken amp.

 

Only times I've ever ran across it has been cheaper amps with the gain accidentally max'd out (more of a white noise than a whine) otherwise there shouldn't be anything if you disconnect the inputs.


I was just thinking of something else. It can be kind of hard to describe things like noises over the internet without actually hearing it in person, but when you say alternator whine does the noise change in pitch/intensity when you rev the engine or does it stay constant when the system is powered on? Also did you run all new wires to all the speakers or are you still patching into the stock speaker wiring at any point? It can be a pain but take your time and trace/track every wire and make sure everything is hooked up correctly and you should be good.

 

and what might that be haha?

Yes its when I rev the engine the sound increases... sorry if i didnt state that before bah. and it gets worse when the car is running, opposed to on accessory power. Ran all new wires to all of the speakers. and oh i know it will be a pain but im gunna have to do it eventually

and as motivation... the trim isnt going back on till i fix this. sooner or later my OCD is gunna force me to fix it so that my car looks clean once again lol

 

Bump....

So yeah i tried to unplug my RCA's and the alternator whine is still there (annoying sound matching the revs of my car) so its either in the speaker wires or in the amp itself... so bad ground or bad amp? this sucks bah

 

If it's coming from all four speaker locations and it is a distinct and changing alternator noise I'd doubt it's the speaker wires. If one speaker in one location had some constant, steady noise it would be more likely but doesn't sound like what you're describing. For a course of action I'd maybe try to disconnect the power from you sub amplifier at the source and temporarily run a short fused power and a ground directly off the battery and see if it changes (leave the RCA cables disconnected from the amp).

 

Yeah i just took the amp and sub out... left in the speaker amp but i still get the noise. and i dont think its my stock wiring because if i pull out the RCAs to my 4 channel the sound is still in the speakers. so basically it has to be my amp or the power/ground/remote wire because those are the only things feeding it. would too large a gauge wire to my amp cause this problem?