Killah Kane

Hey guys, so about a month ago I started my car and for some reason, there was a high pitch tone coming out of my car speakers. I have no idea why but now a month later, it has gotten worse. Now it stays on for a few minutes at a time, then goes away for a few minutes and then comes back on and it is annoying the hell out of me. It sounds like those tones that you hear in the headphones during a hearing test. What is this? How do I fix? My audio set up consists of all the stock speakers and head unit, but I added a sub and an amp which has been connected to the rear speakers to get a signal for the RCA's. My sub and amp have been installed for over 2 years now and had no problems until now. Any idea what the problem is? HELP

GUS'MAXIMA

I have all stock speakers and the same thing happens to me when i pass an area with lots of electrical polls or if i am getting a phone call.

Nietzsche

iTrader: (7)

It can come from many places but it sounds like a signal is clipping. Have you tried disconnecting the amp and seeing if it went away. Basically what happens is the signal gain goes way to high and causes massive distortion which can sound like many things, a high pitch tone is one. It could also be induced rfi or emi but I would think something is shorting.

Killah Kane

Okay so I looked into it more and the high pitch noise is coming from my aftermarket subwoofer. Also when I am playing music, the bass from my subwoofer decreases and then increases then decreases in a cycle and when the high pitch noise is actually happening during the playing of music, the volume of the high pitch noise goes up and down as the bass goes up and down. I checked my ground and its fine. I do not see anything abornormal. What do I do????????? I cant stand this noise!!

Levissan

Well lets see here. Is this happening at high, low or basic volume? If it is happening at high dB or if the bass is turned up too high then I am going with Nietzsche on the clipping. Basically the amp cannot produce enough power for the sub thus distortion then clipping then eventually you will blow that sub.

Lets check your amp!

Lets ask the important Qs:
Where is your amp getting its input (aftermarket HU or stock HU)?
IF STOCK-Are you running rca to the HU direct or do you have an in-line?
Where are you getting your power from?
How may watts/amps are you pulling?
What gauge power you running?
What gauge Gnd you running?
What is your ground source?
What gauge speaker wire you running?
IF YOUR SUB IS DVC:
Are you running series or parallel?
What ohm is the rating and what are you running it at?

To test your sub/amp/power/grnd just take a volt meter to it all and check for fluctuations.

If you can answer these questions for me I can prolly help you narrow it down pretty darn quick.

Jesse

Killah Kane

Hey Jesse,
The high pitch sound has nothing to do with clipping or how loud I play my music. The sound actually comes on when my system is off and I am not playing music. I have been dealing with Subs and Amps for 15 years and this is the first time I ever had this problem. It is a high pitch tone similar to the tones that a person hears when they get a hearing test. I have had this sub and amp in my car for almost 3 years with no problems until now. Here are answers to your questions.:

Lets ask the important Qs:
Where is your amp getting its input (aftermarket HU or stock HU)? STOCK
IF STOCK-Are you running rca to the HU direct or do you have an in-line? IN LINE (HIGH LEVEL INPUTS WITH SIGNAL RECEIVED FROM STOCK SUBS)
Where are you getting your power from? BATTERY
How may watts/amps are you pulling? 750 WATTS
What gauge power you running? 4 GUAGE
What gauge Gnd you running? 4 GUAGE
What is your ground source? BARE METAL UNDER MY SEAT
What gauge speaker wire you running? 14 GUAGE
IF YOUR SUB IS DVC: YES ITS DVC, I HAVE A 12" KICKER SOLOBARIC
Are you running series or parallel? PARALLEL AND BRIDGED
What ohm is the rating and what are you running it at? RUNNING AT 2 OHMS

So what do you think?? Thanks

Levissan

Ooooookay. A couple things jump into mind first and since I have crazy A.D.D I will start there. The first thought is rare but possible, but have you considered the amp? Just a thought. I had the same thing happen to one of my old PPI amps. I won't dwell on that since the possibility is so low. The next possibility is that the speaker wire you are tapped into is a duel purpose. Sometimes a cars are kinda retarded like that. Some of the most basic functions of a car can sometime run through the radio. If you have never heard of such a thing it prolly sounds dumb. We had some GM cars come through for a while there that would through a CEL that the gas cap was open. Well apparently the sensor that tells the car that there is too much air in the gas tank routed its way through the darn radio. Sometimes its dash lights and others (not mentioning names *coughonda, cough, cough*) it was a PITA to even run after market HU. Many people were pushing the factory HU into the dash and running the aftermarket as a stand alone. You can check your speaker wires with a basic test light. Just probe it with the radio off then on. Bimmers are kinda dumb like that too. For some reason the new 7 series like to go from power (after fob is depressed) to ALL GRD after 20 sec of being started.
Your amp hook up and sub hook up sounds fine. Your ground even sound good for the amps your pulling. Just have to figure out where this signal is comming from?

Jesse

Killah Kane

I actually have considered the amp and I think it is definately a possibility. I have hit the amp with my hand while the sound was coming and it stopped after I hit it... But before I buy a new one, id like to exaust all other possibilities. I understand what you are saying about the interference but the reason I do not think this is the cause is because I have had this set up for almost 3 years and I am just now having the problem, even though I have not changed a thing since I installed. Could it be possible that the hi-level input box that I used to convert the speaker wire to rca outputs might be bad?

Levissan

Ahhhh I thought this was a new install. Well we have finally narrowed this issue down to one single category
HARDWARE!!

You know its going to be the in-line, RCAs or amp. That's it!
What amp you running?
What RCAs and where are they ran(specifically)
and finally what brand In-Line?

Jesse

Killah Kane

Actually, you know what I just realized? A few days ago I was trying to diagnose the problem and I actually unhooked the RCA's from the amp to try to narrow it down to either a bad signal or a bad in-line box and it had no effect. The noise was still loud and clear out of my sub even with the RCA's unhooked. I have a Kicker KX350.2 amp and I cannot remember what brand in-line I am using but it is getting a signal from the stock bose subwoofers.

Levissan

Right on. Well the problem has been found. If the RCAs have been unhooked and the signal was still coming out of the sub then your amp is in some need of attention. It depends on how old the amp is but I know Kicker is pretty fair with warranties. On a personal note I would consider upgrading to a bit beefier amp. Are you running a 12" Solo Baric L7 or L5 or one of the older round ones? If your running an older round one I would also consider a possible sub upgrade. If it is not in any budget then I understand totally. If you are in the market I will contact my Kicker Rep and see if he can get me one at cost for yah and have it shipped to the shop so we can get it to you. Bad Amps are nothing to mess around with, don't need any unnecessary fires in the trunk.
I know the KX series is about 3-5 years old now (or better). It has been a min and the specs are no longer on the kicker site but I think bridged at 2 ohms on that model amp will only get you 350 watts/peak. The sucky part about some of the older kicker amps is that they are 4 Ohm STABLE. Anything less will run it hot and strong but shorten its life, quickly. In the last car I built (for my girl) I went with a Memphis Belle 1300. It has a 1 Ohm stable sub out at 1100 watts as well as plenty of power to her mid/high range. Don't mark my word but i was thinking the power and ground for those models were 8awg. If so you really beefed that up!!! LOL. Well hit me back for more questions.

Jesse

Levissan

I just re-read the end of your statement here. I know it was working for you for the last 3 years trouble free but i would still draw your signal from possibly your rear speakers. Your amp will take out the HP crap and give you the lows you want. You might even get more bass control since the factory HU naturally ONLY send so much bass to your factory subs and sends everything to your rears then your fronts. Just throwing that out there, take it if yah want.

Jesse

Killah Kane

I have a Kicker Solobaric L5 (square 12") and it freakin knocks! My amp is definately a bit older but its been great up until now. I actually have it in mono at 4 ohms (not 2 ohms like I mentioned before) and it provides 350 watts RMS. I have been wanting to get the Kicker SX500.2 Amp which is not their newest model but Ive heard good things about it. It provides 500 watts RMS in mono and bridged and I dont really want anything more than that. Ive always used Kicker, I like them alot.

Levissan

I will see what I can get you for more power. I am running a single LS 12 in her car too! yeah it pounds with the 1100watts its eating up. Might have to send you pics sometime. 144dB at the windshield and the sub is in the trunk!!!