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Discussion Starter · #1 ·
Well after that major amp install and after I got everything back working (well mostly) I am left with a buzzing that bugs the hell out of me. The buzzing is only present when the engine is running and it gets louder when I accelerate. Sometimes it goes away after i have been driving for a while, but then I hit a bump or something and buzzing comes back :evil: I checked the connections and tightened them all up. I have been working on it everytime I have time and some DECENT WEATHER! (in Michigan who know's how long that might take)
Here are some of the details of the installation: here's where the wires enter the trunk, through the holes for the cargo hooks.
<img src=http://home.comcast.net/%7Etludwick106014mi/wire1.jpg><img src=http://home.comcast.net/%7Etludwick106014mi/wire2.jpg>
This is what I am left with currently:(spaghetti :oops: ) Workin on the amp rack this week, will post pics when finished...
<img src=http://home.comcast.net/%7Etludwick106014mi/box1.jpg><img src=http://home.comcast.net/%7Etludwick106014mi/spag1.jpg>
I would have some more install pics but I just got the doorsills back down (4 gauge wire is much thicker than what is meant to go under saab doorsills :roll: )

CURRENT ISSUES:
First off now that there are 4 rca's back there the head unit doesn't go back flush into the dash:
<img src=http://home.comcast.net/%7Etludwick106014mi/HUout.jpg>
Also there is an ANNOYING buzz that comes from all the speakers when the car is running, there is no buzz whatsoever when the car is off, (running on bat.) I have the rca's run down the pass side and the power goes down the driver. Someone recently told me that the amps might not be grounded properly. I have the ground attached to a bolt goin through the bottom of my trunk, however it might be rusting, could that be causing it? Here are some pics of the ground:(top)
<img src=http://home.comcast.net/%7Etludwick106014mi/ground1.jpg>(bottom)<img src=http://home.comcast.net/%7Etludwick106014mi/ground2.jpg>

The plan was to get it bumpin not buzzin :roll:......
-Tom
 

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HNNLIC
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I used to have that buzz as well. Its called the "Alternator whine". Its because when your system is running its drawing power straight from your altenator...whereas when the car is off, it drows power from the battery.

I solve the problem by installing a capacitor. This allows for the extra power that your system draws, to come from the capacitor, and not drain it from your alternator.

I have to 12" 500w 1000peak subs hooked up to one 1.2 Farad Cap...so Im sure a single cap will help for your setup too.
 

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Discussion Starter · #4 ·
Thanks!

That makes A LOT of sense! A capacitor acts as a filter right? So my next question is how big of a capacitor do need? I push about 600W RMS.

Thanks,
-Tom
 

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oh man dude - V6POWER- I just looked over your site, nice site btw, you got a nice stereo set up. Nothing heavy - but it's serious. I have that same Sub - but two 10" instead of 1 12". How does it hit? 8) But overall - you have a nice car man, shame it's got the V6 ;) keep an eye on that chain man...
 

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Discussion Starter · #6 ·
Thanks BurnsSide for the compliments on the car and site;

The fact that it has the V6 (and an auto tranny) wasn't my first choice, but I got it right after my 9K was T-boned and I needed a car, plus I got a good deal.

But, anyway I love the 12" I wish I had another one :twisted: , but it hits hard enough for me right now. What do u think of the 10's?

-Tom
 

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HNNLIC
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The capacitor actually is a type of power storage. Its holds a certain amount of electrons( in my case 1.2 Farads). This storage helps to keep the power flow consistant. You'd only need a 1 Farad Capacitor since your only a single 600w Sub.
 

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first you should clean up that mess of wires!! and then check all your wires to see if something is grounding out...or any bad grounds....
 

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playing with farads can be extremely dangerous, my dad gave me one to bring into my ap physics class cause we are working with them, and my dad works at verizon, so he's got some big ones, and this one he gave me was about 100,000 farads if i remember correctly, well, it took about an hour for the thing to charge, and class was almost up so we had to discharge, the way we discharged the smaller ones was with a screwdriver and touching the two posts, so we decided to do that with this one, really really really bad idea, the thing made a huge noise and a bright flash, and shot the screw driver through a window(which was hilarious btw) good thing no one was in the way, cause it would've impailed them

a 1.2 farad should be pleanty for your system, and a capacitor acts as a mini battery, it holds charge and gives charge like a battery, but it can make a little bit of power last a long time, which is why it's better than a battery.

also, you could ground your stuff in two spots, get a router and make the them ground in more spots, you can never have enough grounds. when i got in the accident with my jeep, they disconnected the negative post on the battery so nothing electrical would work, then for some reason someone tried to start the car, and since the amp was still grounded, and that nice 4 gauge wire running to it, the car started, and blew the piss out of my amp.... good thing mtx has warrantees!

it's a good thing you are ok after your accident

~justin
 

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saabguy said:
playing with farads can be extremely dangerous,
Playing with caps surely can be incredibly dangerous, but not being dumb (discharging through a screwdriver!) isn't. ;)

also, you could ground your stuff in two spots, get a router and make the them ground in more spots, you can never have enough grounds.
I would strongly reccomend *against* grounding any audio equipment in more than one location. Unless you get lucky, you'll probably introduce extra noise into the system. If the two gounding points aren't (electrically) identical, you'll create a ground loop.

One good, solid ground should be fine. Just make sure it's a metal-to-metal ground (no paint around the hole you drill) and seal it up afterwards to prevent rust.
 

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Ground loop.

Your aftermarket head unit and amps are grounded in different locations with different electrical potentials. Try to ground all your audio at the same place.

For your install, I recommend grounding with the grounding bolts behind the dash fusebox. Run 4 ga there and crimp it with the head unit ground to a ring connector. Bolt it down at the grounding bolt. Best ground is to wire all audio including head unit directly to the -ve terminal on your battery.

With all the power needed for your amps, definitely install a cap at least to your sub. You might also consider a second battery such as an optima yellow top. Your headlights are probably dimming when you crank it up.
 

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Discussion Starter · #12 ·
so far....

What about one of those ground loop isolater sets they sell at radio shack, would that do it? For right now I just ordered a 50 amp noise suppressor off of ebay on the advice of an electriction friend:
<img src=http://pics.sell2all.com/hd/LN-77.JPG>

Discribed as:
Tired of hearing ignition or alternator noise from your car.Introduce yourself to the Legacy 50 Amp Transistored Noise Suppressor, which eliminates these annoying sounds and make other jealous of your incredible system sound.Act now on this great deal while its lasts!
http://cgi.ebay.com/ws/eBayISAPI.dl...=14932&sspagename=STRK:MEBWN:IT&rd=1#morepics

P.S. yes, I still plan on getting a capacitor...eventually
 

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New to the forum, but have info on this old topic...

FWIW I was picking up alternator whine when I first installed my amp. I narrowed it down to the rca cable. I had them running on the opposite side as the power and was still getting noise. By blind luck I bought a set of stinger twisted pair rca cables with no shielding. These worked! I have two sets running from the head unit to the amp and NO noise! I had bought twisted pair Monster and RF and both picked up noise.
 

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Yeah first step would be to clean up that nest of wires, You do not need to buy a cap to get rid of alternator whine, you just have to eliminate a ground loop, or the RCA's being too close to power wires (or if you have seperates, move the crossover networks away from power sources and see if they are the source of the noise) As far as RCA interference, you could check behind the deck, try and have the least amount of contact between the RCA's and power as possible. I would check everything else first, including grounding to different locations before using a ground loop isolator. It's better to do it right then to have to get some stupid box to fix your mistakes. You could always do twisted pair RCA's they help alot with noise, but you should be able to use normal cheap RCA's and not have the problem you are experiencing.
 

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HNNLIC
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I too have my power wires running on the opposite side of the car, and no wires crossing or in contact with the power, but still get the whine when my Cap is unplugged.

Depending on how powerful your system (and given the amount of output from the altenator = avg. 14.2 Volts), then you'll need a Cap or not.

I chose to use a cap cause I have a fairly powerful system. In fact for my next upgrade I'll need to have a second battery installed rather than another (or larger) capacitor.
 

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This is most likely a ground loop issue, I would strongley recomend grounding the headunit to the same place as the amps.

ground loops are caused, because if you took a VOM sensitive enough and touched 2 parts of the car frame far enough away from each other, you will be able to measure some potential. SO that mean you can have potential between the head unit and the amps, which will cause noise in the system.

Another probelm could be, a bad signal ground on the RCA's, this is the outer wire and that spaided part of the RCA connector.

Logan Lesile said:
but you should be able to use normal cheap RCA's and not have the problem you are experiencing.
This is very true, when i was putting together my system, I was being cheap with my wires, unti I decided the final # of amps and how it was getting wired, Really all these "high end" expensive RCA's are mostly just for looks, yes you need good sheilding, but with my carefully wired system I have no whine and I am using radioshack normal RCA's.

I have no subs yet, but when I am crazy enough to have 2 amps just for my front speakers and I get no whine,(100 watts RMS to each 5.25 woofer and 40 watts RMS to each tweeter (obviously the tweeters dont even utilize probabaly half the power of the amp, but its what I had and its not hurting anything)and of course power wires run down opposite sides of the signal wires.)) I am betting on it being a ground loop

Not saying I wont get good RCA's because I plan to once i put the sub amp in, just so it has a cleaned finished look.
 

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Oooohhh interesting WyldSaab you sound pretty serious if your bandpassing your front seperates. What other stuff do you have (like what kind of equip) I dunno V6POWER do what you want about the cap, but if I was in your position I would save my money, and go over all of the wiring to make sure you don't have anything wrong. (Blaque_Out, my friends mom's 91 legacy wagon has alternator whine, and all of its stuff is factory stock tape deck and speaks. There has to be something else wrong other then low voltage and some sort current issue in order for him to experience the whine.) I guess one plus with the cap is you could ground all the amps to the cap, so that would eliminate some of the ground points....
 

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IMO i do not believe a CAP will get rid of a alternator whine, its not low voltage causing a buzz or whine, its a bad ground somewhere, i got the same thing when my AI-NET cable became unplugged from my XM tuner, since it turned the entire shield of the AI-NET cable into an antenna, as it did not have a signal ground.

Yeah I am pretty serious about GOOD CLEAN sound, i could honestly care less if someone can here me bumping from blocks away (thats just a nice side effect), granted once the subs are in they might be able to. but unlike other people who do subs first I have done good speakers first. Also some people just care about how loud there bass is, I care about if I can feel it, and get it loud, but not anoying loud where all the sub does is make your eardrum vibrate like crazy, I absolutely hate it when this friend I have just turns his subs up and all you hear is loud obnoxious halfassed bass.

anyway the equipment i have is:

Alpine CDA-9815 for my headunit
MB-Quart Premium 5.25 components (woofer is mounted in door with a 3/4 inch thick MDF adapter plate and the 1 inch dome tweeters are in the dash where I made adapters so they would fit the stock holes)
The speakers are Bi-Amped, meaning I am not using the passive crossover the speakers came with, my headunit serves as an active crossover the crossover point between the highs and mids is set at the speakers recomended crossover point of 2.5khz. I can do this because the headunit has 3 preouts.

so the "front" preout goes to the tweeter amp
the "rear" preout goes to the mids amp
and the "sub" preout will go to my subamp once i get it

The tweeter amp is a Alpine V12 MRV-F303 which is a 40X4 amp (since this was 4 channel it used to power the tweeters and woofers, but 40 watts just wasnt enough for the mids) so now I have....
An Alpine V12 MRV-757 which is 100X2
and my XM tuner

The subs that are going in are the 2002 model of the 8 inch Kicker L7 solobarics
I listen to music that usually have fast bass, and these subs used to be in my friends trans am, and what i like about them is that they are fast have a very tight clean sound, and can go low when you need them to go low

Now I just need to find a AMP for them, I was thinking of the Alpine 1507, anyone into stereo stuff should know about that amp, they still go for 300 plus on ebay.

Anyway I have no fancy wires, flexible 4ga battery cable from levine automotive and radio shack RCA's and I have no noise in my system whatsover.
Once its time to finish up the install and mount the amps permanetly i will get some nicer power cable and RCA's so it looks nice, but thats about all the fancy schmancy RCA's do for you, and this is make it look nice
 
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