Another f**king stereo question, need a stereo EXPERT Options

[ninefourteener]

Last night I had Best Buy install some stereo equipment in my car. All of it was 100% new, and unopened, so it's highly unlikely anything was defective.

Already installed is a VERY nice Pioneer 8500 CD player

Installed a JVC 500 watt 4-channel amp. Not overly expensive, but not junk either.

Installed 4 brand new Pioneer 6.5 inch 3-way speakers in the factory holes.

In addition to my passenger door not opening from the inside, there are several other problems:

1) I can turn the volume about as loud as it was without an amp.... whether I use the volume on the amp or the stereo. Once I go above that, the stereo "shuts off" when bass hits, or.......

2) Occasionally, I'll get this rediculously loud "squelching" sound that won't go away until I turn the car off.

3) I spend $80 on a Rockford Fosgate insulated Amp wiring kit, but I still have alternator whine.

I have an appointment today to get their best technician (15 years experience) to "re-do" the entire thing... but I'd like to have a basic knowledge of what "could" be wrong. Basically, I'd like to know some good questions to ask, or solutions to recommend.

Please don't respond if you're just "guessing". If you're very familar with how this stuff works, I'd really appreciate any help you can provide. I'm not doing any work, but I don't want to just look stupid not knowing what to ask, and accepting whatever they tell me. Thanks.

Matt

[rhodyguy]

can't help with the stereo, but, the door worked before they put their hands on the car?

[Dave_Darling]

Door opening: They swapped the screws for the window crank and the inside door lever surround. The window crank one is just barely longer, and keeps the door lever from pulling back all the way.

Stereo shut-off: Probably not getting enough power. When the bass hits is when the stereo calls for the most power. It is probably detecting that it can't get enough juice, so it goes into shut-down. A heavy-gauge wire from the battery to the "unswitched" input of the amp is the likely cure for this. (Put a fuse of the appropriate rating in the wire, no more than 18" of wire run from the battery!)

Squelching noise: Not sure.

Alternator whine: Could be a bunch of things. Try running a big fat ground wire from the stereo's ground terminal to the amp's ground terminal, and then back to the battery ground post. That should help if there's any kind of ground problem... A big fat cap on the power supply line might also help.

--DD

[ninefourteener]

I'm sorry, I should have "OT'd" this topic... it's in my Acura, not the Porsche. Strangely enough, I've owned the teener 1.5 years, and have done only 1 repair.. the battery. The teener doesn't break.

Nevertheless, I think in the door, the linkage just got bumped off track.. no biggy.

As for wires/grounds/etc. They used an insulated and fused 8-gauge power wire to power the amp. Insulated RCA connections, and even Honda adaptors to wire the speakers in. They used all the right parts.. I spent $250 on the installation/parts.

If the stereo is shutting off fron lack of power, isn't that what the amp is for? If an amp is hooked up, shouldn't that be enough to power 4 6.5s??

I don't even have subwoofers in the car yet, these are just 4 factory upgrade sized speakers.

Also, once the stereo uses RCA cables directly to the amp (instead of power directly to the speakers), doesn't the radio cease to provide power to the speakers anymore? Shouldn't the amp be doing that?

[Pnambic]

I know you said you don't want guesses, but thats pretty much all we can offer since we weren't there during install. Read on if you like.

The issue may not be with the stereo set up (though a half farad capacitor prolly wouldn't hurt, especially after you add a sub). Have the alternator and battery tested. Places like Autozone and Advance Auto Parts will do it for free. I killed an alternator and battery with a new stereo setup about 8 years ago and it acted very similar to what you're talking about, but I never had a squelch...

If you check the alternator and battery before you go to Best Buy, at least you won't be laying in on the guy if its not his fault. (IMG:style_emoticons/default/smile.gif)

Also, just b/c its new doesn't mean there's not a defect. It happens. Make sure they switch out the big stuff like the amp, run alternative wiring straight to the battery outside the car to make sure none of the wiring was damaged when they ran it, you know, the usual troubleshooting stuff.



Almost afraid to admit it, but in high school, I custom built a box to turn the entire trunk of my little hatchback into a 4-compartment sub/speaker box. Had 2 12" Kickers and 2 6x9 Pioneers using a combined 7 cubic feet. All ran by a 300 watt Jensen amp (I know, cheap crap). It was loud....I'm glad I grew out of that though. (IMG:style_emoticons/default/wacko.gif)

That stereo may have been the death of that car since it was so loud, that I didn't hear the death cries when a rod broke, puctured the oil pan and all the oil drained out on my way to school one morning. I didn't know anything was wrong until the engine seized. Live and learn I guess.

[skline]

I can sum up most of your problem with the stereo system with 2 words, Ground Loop. No caps in the power lines, no additions to the system, just get rid of the ground loop. If you do it the way DD said, you will only make the ground loop worse. You need to eliminate the ground circuit looping in the car. It sounds to me like they pulled the ground off the radio and thats not a good idea. Good luck with the Good Guys team, sometimes they get a decent installer.




Let me add to the cap in the power supply line, a cap is used to limit the amount of current to a certain setting depending on the spec, it is not what you need if the power is cutting off when you turn it up. That is also probably caused by the ground, as well as the amp making the noise you described. I have seen it about a dozen times and it always root back to the ground.

[charlesmac]

Matt, the squelching noise is going to be a bad RCA connection somewhere in the system. Get them to check all. At the radio and the amp. If it doesn't stop, they need to replace the RCA cable and/or check for a loose solder joint on the board of the amp or the head unit where the RCA's connect.

charles

[Eric_Shea]

The stereo shutting off is an ohmage issue. My Guess: They have wired your speakers in "Parallel" and have brought the ohmage down below the minimum your amp wants to see. If that's the case have them rewire them in "Series" or get an "additional" amp. Mr. Stereo Guru should be able to take an ohmage reading at the speaker cables where they attach to the amp. Make sure it matches your amplifiers specs.

The lower the ohmage the harder the amp works and the more power it puts out. The more power, the more heat it produces. Almost every modern amplifier (home or car) has an automatic protection circuit that will shut the amp down when it recognizes a heat or ohmage problem. These same amps will idle all day at a lower volume but once you get to the higher levels the amp will shut down. Basically; the amp is protecting itself.

The "squelch" sound is probably what they call "White Noise" which is basically all frequencies playing at once. This can be caused by a cable short from your "source" device (radio/CD whatever) or it can be a defective FET or op-amp in your power supply. If you've overheated the amp enough with improper ohmage then you may have damaged the output section of your power supply (the JVC). Based upong the fact that it goes away when you shut off the car then I would suspect the later.

It's a good chane the JVC was defective out of the box.

[ninefourteener]

All this trouble..... turns out it was something simple.

Problem #1...... the JVC Amp I bought was a piece of shit. It was cutting out and making noises because it was overheating.

Problem#2...... the guy that installed it had the settings wrong on the amp, as well as the stereo, and it was overloading an already crappy amp.

Fortunately.... the second guy that re-did the installation was very knowledgeable. I returned the JVC and got a Sony Xplod 600watt 4-channel.

The settings wer set correctly on the amp and the stereo, and everything works great... couldn't be happier. I drove home on the highway with the windows and the sunroof open, and couldn't even hear the wind.

(IMG:style_emoticons/default/beerchug.gif)

Thanks for all the help!

Matt

[jporsche914]

Charge your battery!! I had the same problem with the stereo turning off after hooking up my amp for my subwoofer. I set there playing with the stereo for a while before i put in amp and sub on so by the time i got to playing with the amp and sub the battery was dead and the stereo just turned off. Maybe you have the same problem. Also the whinning noise may be from a bad ground i had the same problem. Make sure you sand the the paint off for the ground wire that made my stereo sound awsome. Where did you mount the amp? Where did you hook up the ground wire? Hope this helps