Put in a new amp, now I have a whine coming out of the speakers. Bought a noise filter, but it didn't help. Any help out there???

 

Check your grounds. Make sure they are at least the same size or larger than the power cable feeding the AMP. The ground needs the run to the frame and have an exposed (scraped) metal surface to have a good contact. Also, make sure your power cables do not run parallel to your speaker cable. Try to run the power under the car or on top on the driveshaft hump and the speaker wires down one of the sills.

 

Also make the ground wire as short as possible. The shorter the better preferrable under 24 inches. I know that is a tall request in a vette. My ground wire is about 3 feet long with no noise on an 800 watt 4 channel Kenwood amp.

 

Thanks, I will try that. Also, the whine gets louder when I push on the window button.

 

how close together are your power wires and your rca input signal wires? too close and they will do that. ditto on the grounding. i just mounted mine right to the battery. works like a charm. What kind of amp are you working with?

 

Kenwood. Four channel. I just changed the ground from the battery to the frame, no luck. My power wires and rca wires run right next to each other, think that's what it is? Is there anything I can put on the alternator?

 

try asking here:

http://forums.corvetteforum.com/forumdisplay.php?f=20

 

If it is a continuous whine that increases with engine speed, you are probably getting ignition pulses into the power system. Ignition wire shielding and strategically placed filter capacitors (on motors and high-current switches) are the usual way to address that problem.

 

I bought this alternator off e-bay, probably made in China. Think I could put some kind of filter there? Before I added the power amp, I had no problem with the head unit.

 

I always struggle with the whining when I hook up stereos. I recently had the same problem and took it by best buy. They grounded it out correctly for $40. They also adjusted a few other things I did not have set up ideally.

 

I have the Kenwood KAC8452 800 watt 4 channel. My complete stereo system is in the rear of the car. I operate the headend with a remote control and I left the OEM radio in the dash for the old school look. My RCA wires and power wires are seperated by about 10" of space. I am pulling power foir the head in unit and the amp straight of the battery. I put an inline switch in to kill the power to the headend unit so it won't drain the battery. I hooked up everything else normally. My ground wire is attache to the frame. I went through the drain hole in tha battery compartment to get to the frame. Make sure you scape paint an etc off the frame before you attach the ground wire. I used a ring type compression lug and put it under an existing bolt in the frame.

 

Get one of these and put it on your alternator. You can also install it at the junction block under the drivers side fender where the alternator is connected. I installed one when I had my older radio and it cured 98% of the whine.

http://www.ecklers.com/product.asp?p...7&dept_id=1013

 

Thanks, I'll try that, and also move my wires apart. I wonder if I could buy that part locally? Thanks for all the help. I'll post my results.

 

Wow a 20$ 38K uF capacitor, unbelievable

 

Sounds like I did everything you did, except I didn't run separate power for the head unit, I used the red wire off the original harness. And I grounded the head unit to the tunnel floor.

 

You must have a better store than we do. They installed the last sytem in the car, and everytime I started it, I had to reset the clock!!!!

 

You probably have a ground loop. The shielding should be grounded at 1 end only. Preferably the source.

 

Car Audio Noise Troubleshooting
One of the most frustrating aspects of car audio is noise in the system. Unlike home audio systems, car audio systems have many sources of noise to deal with. Here's a few of the most common noises found in car stereo and how to fix or avoid them.

Alternator Whine
Alternator whine is the granddaddy of car stereo noise. The most common and the most annoying. Alternator whine will be heard as a high pitched whine that will rise and fall with the engine speed. Most of the time this is caused by a poorly chosen ground for a piece of equipment. It is usually cured by grounding the equipment directly to bare metal on the chassis rather than an available factory ground bolt as is often used to save time. You'll also need to make sure your charging system is in top condition and that your connections between the battery and components are secure as well as the integrity of the factory ground strap, an often overlooked component. You might also consider switching your RCA cables to a twisted pair model. Twisted pair cables will usually be less prone to noise than their coaxial counterparts.

Accessory Pop
Accessory pop is associated with one particular electrical event in the vehicle. This can be switching on your turn signal, headlights, brakes, windshield wipers or even the rear window defrost. These high current drawing accessories are causing a voltage spike that is traveling into your car audio equipment with the result being heard as a sharp pop. Adding a small bi-polar capacitor (0.47 uF) between the accessory's power wire and ground will often absorb these surges. You may need to place the capacitor on the load or the power side of the switch (maybe both). See the diagram below to see how this is done. Note that the diagram is slightly different if the accessory has a relay in the circuit.


Accessory Pop Absorption Circuit

Body Rattle
I'm sure everyone has heard a car booming down the street with the body panels shaking and rattling with every bass note. This is an extreme case of body rattle. Less noticeable examples are interior panels that are worn and may slap together when a bump is hit. Door noise is less common and is usually more of a problem on the less expensive cars. Large and luxury cars are usually built with thicker metal and more sound absorption materials and are less prone to body rattle. Body rattle can be solved as easily as tightening the bolts and screws that hold the panels together or may require a full array of noise dampeners.

Noise Dampeners
Noise dampeners can be any material that is used to reduced body panel noise. The thick padding underneath the factory carpeting is a type of noise dampener. Various clays and putties are also used to act as an absorber between two body panels. The most commonly available product in the automotive aftermarket is the viscoelastic sheets and spray on materials. The most well known brand of sheeting material is Dynamat, a product of Dynamic Control. Other well known manufacturers are Stinger (Road Kill), Scosche (Accumat) , Rockford Fosgate (Dead Skin) and B-Quiet which makes a product called Brown Bread. Dynamat has the most extensive product line as this is their specialty. B-Quiet also specializes in sound deadening and though their line is not as varied their prices tend to be less expensive. Sheets tend to work well and are relatively easy to apply. If you have a rattling license plate than adding a layer of sound deadener behind the plate will definitely help. Rattling trunk lids may be caused by a loose trunk latch or a worn weather seal. Have this checked out by a qualified body repair person. Liquid spray on deadeners are popular for the interior door panels but are a little messier to apply. These are best left to the professionals or the adventurous DIYer. Keep in mind that sound deadeners tend to be heavy so if vehicle performance is important to you make sure you keep the weight down by using sound deadeners sparingly or by going with a lighter weight deadener sheet or spray on material.


Application of sound deadening sheets
(Image courtesy of Dynamic Control) Application of sound deadening spray
(Image courtesy of Dynamic Control)

Band Aids
Noise suppressors are not a solution in my opinion. Instead of fixing the cause of the problem a noise suppressor will try to cover it up in a "band aid" approach. This is a poor attempt to fix the problem and doesn't always work. It costs extra money and the noise filter drops the voltage going to the component as well. This is especially important with amplifiers as their power output is usually dependent on the input voltage. Less input voltage, less output power. I feel strongly that a shop owes you a noise free installation without charging you extra for the work. If they can't figure it out then that's their problem. You shouldn't have to pay for their inexperience. Get it in writing that they will give you a noise free guarantee with no extra charges. Have them sign it and you keep the original.

Proper Grounding
Most non-equipment related problems in car audio are the result of poorly chosen ground points. Always check the integrity of every connection including the battery, head unit, amplifiers and signal processors. Any part of the audio system can bring noise into the system. In general your connections need to be secure (grounds should be to the chassis), the charging system should be in top condition and all factory connections (battery posts, ground strap, alternator connections) should be secure. You may need to increase the size of your factory ground if you install a very large stereo system. It should also be noted that the negative battery post is usually a terrible place to ground car audio equipment. All of the ripple (noise) from the alternator and other items in the vehicle travel to this point. If you choose it as a ground point then you are inviting all of these elements into your sound system.

 

I guess I don't follow you on that one.

 

http://forums.corvetteforum.com/forumdisplay.php?f=20

try here