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well everybody, it finally hit me that i don't need 2 competition 12 inch subwoofers in my 73 mach 1 that weight 20lbs each and with the box it weights roughly 90lbs. (sure it did slow me down). so i took out those subs and i hooked up the door speakers and the rear speakers to the same amp i had pushing the subs. (kenwood 600watt 100watts x 2) all the speakers are 40rms watts so it's a perfect size amp to push all 4 speakers.

when i was done and i turned on the music. i couldn't believe my ears, the sound was so clear. it was LOUD and CLEAR to be exact. i asked myself why i didn't just do this from the beginning. i also have 2 speakers in the dash board. with 2 speakers in the dash, 2 in the doors, 2 in the rear, it makes the car sound awesome.

but then, i wanted to take it out driving to listen to the radio i heard a buzzing sound. that buzzing sound is coming from all 4 speakers connected to the amp. i made sure it was the speakers by putting my head right next to all 4 speakers. i turn down the volume to "0" and the same buzzing sound stays there. the buzzing sound DOESN'T change volume though. at 0 volume you hear it the most, but at 1/2 volume you don't hear it anymore. anything above 0 and below 1/2, the buzzing sound goes down. it's only because the music volume is louder so it cancels out the buzzing sound. but you can still hear it at the same volume at voume 15.

however if you turn off the car, the buzzing sound goes away. start the car right back up, the buzzing comes back. turn off the car, the buzzing goes away.

i then looked at the amplifier. there is a switch that says "stereo or mono", knowing it's for 4 speakers i put it to "stereo", and there is a filter switch, saying "off or lpf". low freq, means bass as in short. i put it on "off" because i do not want the speakers on the low freq. side. if you do all you hear is bass out of the speakers. if you put it on "off" you hear the buzzing sound. if you switch it to "lpf", the buzzing stops.

what in the hell can cause this? i hear it could be the condensor in the dizzy can do it, or spark plug wires. but it never did this to my subs when i had them hooked up. what else can cause radio interference. if it's something under my hood. it's funny because it didn't do it when i used my amp to 2 subs.

though i ALWAYS used this amp for subs. i haven't ever used them for speakers. people told me this specific amp is PERFECT for speakers and not for subs. thats what made me (part of ) hook the speakers up to the amp.


PLEASE HELP!!!
 

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Discussion Starter #2
oh yea, the buzzing sound only goes on when the car is running. but if you hit the filter switch to "lpd" a.k.a. low freq., the buzzing sound goes off. but the speakers only produce bass. (not wanted)
 

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Sounds like you have alternator whine. What you need is a noise supressor. If you want one really quickly, but kinda expensive, go to Radio Shack. They have them I believe. It's cheaper to go to a sound store such as Rolling Sound or the like. There are two different kinds of noise supressors. One hooks to the power feed on the amp, and is limited to a certain number of amps through it. The other is called a ground loop isolator and it hooks to the RCA cables going to the amp. It sometimes takes both to kill the whine completely. For an amp that size, I would recommend at least a 30 amp noise supressor if that is the kind you want. The ground loop isolator is cheaper, but tends to not work as well.
 

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Discussion Starter #4
thing is what exactly is making the noise? why can i do if it really is my alternator whining?

do you really think a sound sur. something will work? if it will i will go out and buy it. but why is it making this noise all of a sudden?

OH YEA, I FORGOT TO IMPUT THAT I DID ONCE ACCIDENT FORGOT TO PUT BACK THE AMP POWER WIRE ON THE BRACKET SO IT TOUCHED THE HEDDERS FOR ABOUT 2 DAYS AND IT BURNED THE PLASTIC OFF OF THE WIRE. SO THER EIS A 2 INCH LONG BURN ON THE WIRE. SO I TAPED IT UP AND MOVED IT OUT OF THE WAY.

could this cause this?


also, could you explain more what a sound supressor is?

<font size=-1>[ This Message was edited by: xoliex on 4/7/03 10:06am ]</font>
 

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I am no expert but it just sounds like you are getting feed back from the electrical workings of the car thru your stereo.

Are you running a high energy ignition system?

Another source of info would be your local stereo store or outlet, they might be able to answer your questions.
 

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Discussion Starter #6
yes, i am running a MSD 6A BOX. though still using duraspark wirs and dizzy.

another thing guys, I'M ON MY ORIGINAL ALTERNATOR STILL, AND IT'S NOT CHARGING OVER 13.0 VOLTS.
 

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Nastystang is right ignition is a major culprit and there is devices available for isolating that the other is extra grounds right to the frame make sure the motor is grounded clean all areas where the ground is attached I really dont like using the suppressors but they do work and for is notorious for engine noise but I would really spend some time with at least 8 guage wire grounding it at the amp, head unit, engine etc. good luck

Robert
 

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Discussion Starter #8
i am using good size wires. i am using 1 guage battery cables and i'm using 4 guage power and ground wires on the amp.
 

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Wow, and I thought the last few years of playing with car audio were useless.

Alright, what you have is normal. All of my speakers have a very light buzz with my amp.
I am running two 7x10's, two 6x9's, and a component set up front. This is all connected to my amp-a Zapco 360. It is loud and clear. But here is the deal, at idle, when the speakers "power up" you cant tell with a stock system, but when amped they make a slight buzz, its the constant power running to the speakers. The reason why its like this is because the speakers need a constant ampount of power to eliminate a "voltage spike" which can occur. Dont worry about the buzz, it wont hurt anything at all.


Oh yeah, I built two sub boxes and have one behind each seat. All I have to do is disconnect the wires and pull them out before I race
 

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Discussion Starter #10
i know what kind of light buzz you are talking about. but this is not a normal buzz. this buzz is at least 1/3 full volume noise. it's a decently loud buzz. to complete cancel out the noise you have to put it to 1/2 volume, even then you could still hear it a little bit.

the noise is hurting my head.
 

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MSD sells radio noise surpressors. When I installed my MSD, I had the buzzing noise in place of the music from my radio. Put one on, MSD #8830, no more buzzing. Might try it.
 

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Discussion Starter #12
can the msd box ignition really be causing radio interference? i wonder why it didn't cause any when i had my amp hooked up to 2 12 inch subs.
 

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The remote power wire "primary wire" for your amp "on" switch is probibly coming from a bad source. Also you will need to use resistor type spark plugs if you don't have them already and GROUND the heads to the chassie next to the battery ground.

Try pulling the "on switch" power from different locations in the fuse box or better yet... directly from the "amp on" wire coming from your head unit if it has one.

No amount of engine noise should be coming from any speakers on any car! period!

Apply this to your crossover if your running one also.

<font size=-1>[ This Message was edited by: SCOTT on 4/7/03 11:23am ]</font>
 

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On 2003-04-06 22:52, XolieX wrote:
can the msd box ignition really be causing radio interference? i wonder why it didn't cause any when i had my amp hooked up to 2 12 inch subs.
Sub frequencies don't go high enough for most noise interference. An alternator noise is a whine that winds up and down with rpms. Plug noise is a definate popping noise that speeds up with rpms. Ignition noise is less whiney and more like static. If you can figure out where it's coming from, you will have better luck filtering it out from the source.
 

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Discussion Starter #15
actually, the noise stays at one volume. it doesn't go up or down with the speed of the engine. it has a constant noise level.
 

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I NOW HAVE GREAT NEWS!!!!!!!!!!!!!!

I DID EXACTLY WHAT YOU GUYS SAID AND I SEPARATED THE RCA CABLE ON THE OTHER SIDE OF THE CAR. THE NOISE WAS GONE. what i did was i pulled the rca cable out under the carpet and i ran it in the middle of the car to see if it really was the rca. the noise minimized. and i found the closer i put the rca closer to the power wires near the amp the more the noise came back (not as much with the rca zip tied to the power wire throughout the whole car). i completely separated them and there is almost 0 buzzing now. at "o" volume you can't hear it from your seat, the only way you can heare a slight slight sligt buzz now if you stick your head on the speakers. it sounds awesome.


THANKS GUYS!!!!!!!!!!!!!!!!
 

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It is my understanding that you should use spiral wound plug wires when using high energy ignition systems so as not to interfere with radio traffic in the police and fire rescue band, I am thinking if you are not, that it may be a good idea incase it is the last piece of the puzzle with your buzzing problem.
 

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I have had this problem, if you ran any of your speaker wire or rca's next to or close to ANY!! power wire including your amp power wire or remote wire you will get a altenator feeedback. All you have to do is seperate rca's and speaker wire from any other wires as much as possible and your little problem should go away.
 
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