Engine noise from amp

[finkster]

This is if it's alt whine, such as engine revs coincide with frequency of the noise. Here is an excerpt from termpro for diagnosing alt whine. Full artice here

http://www.termpro.com/asp/pubs.asp?ID=121

Alternator Whine

To me, alternator whine is the most annoying form of noise. For those of you who are lucky enough never to have been exposed to alternator whine, it sounds like a miniature siren that rises in pitch with the speed of the engine. Alternator whine is almost always caused by a ground loop. The following steps will aid you in locating and correcting a ground loop problem.

1. Verify that all levels are set properly. (Click here for related article.)
2. With the system turned off, unplug the RCA inputs to the amplifier.
3. Start the vehicle and turn the system on. If the noise is gone go to step 8. If the noise is still present, it is coming from the amp or the speaker wiring. Continue.
4. Turn the system off and disconnect the speaker harness.
5. Start the engine and verify that no noise is present. In a few rare instances, I have actually heard speakers reproduce noise without being connected to an amplifier. This noise was being induced by power cables that were very close to the speaker wire. If you do have this type of noise, reroute the appropriate speaker lead and go to step 3.
6. With the speaker harness still disconnected, check to make sure there are no shorts between the speaker leads and the chassis of the vehicle. A shorted negative speaker lead will create a ground loop by establishing a second audio ground reference point. If you do have a short, trace the wire out and repair it then go to step 3.
7. With the RCA inputs and speaker harness still disconnected from the amplifier, use your VOM to measure from the shield of the RCA jacks on the amp to the chassis of the vehicle. This reading should not be a direct short (100 ohms or more is acceptable.) If this reading does indicate a direct short, you might have a defective amp and should contact the manufacturer for verification.(Note that there are a few "inexpensive" amps or boosters on the market that have their audio ground and electrical ground commoned internally. For units of this type, the information in this article will be of very little value.)
8. If youve made it here, you know that the amplifier and speaker wiring are okay.
9. Connect the accessories in front of the amp (crossovers, equalizers, etc.) one at a time and check for alternator whine. When each device is tested, there should be nothing plugged into the input of that device. In this way, we will work toward the source unit piece by piece. Be sure to turn the system power off before connecting or disconnecting any cables or accessories.
10. Repeat step 9 until all accessories have been tested.
11. If a particular accessory is causing noise, try disconnecting its power ground wire. Go to step 9.
12. Now its time to connect the source unit. Do that now and test for noise.
13. If noise is present, try unplugging the antenna. If the noise goes away, you will need to use an antenna isolator. This little gismo opens the shield wire of the coax to eliminate the ground loop caused by the ground at the antenna.
14. If you still have noise, try connecting the source units ground wire in another location, preferably as close to the source unit as possible.
15. Does the noise vary in amplitude when you adjust the volume control? If it does, the problem is probably power line related and not a ground loop. If this is the case, run the source units B+ (yellow) wire directly to the positive terminal of the battery. If this doesnt do the trick, you will probably have to use a power line filter on the source units B+ (Yel) and Ignition (Red) wires.

Ignition Noise

Ignition noise is another type of noise that is quite annoying. It usually sounds like a popping or buzzing sound whenever the engine is running. The best cure is to remove the motor but since we cant do that, we will have to rely on some other form of remedy. Follow the steps below to eliminate or reduce ignition noise.

1. Make sure you are using resistor type spark plugs and resistor type plug wires.
2. Determine where the noise is coming from. If the noise is a popping sound that occurs 2 or 3 times a second, you probably have a loose or bad plug wire. First, make sure that all plug wires are seated properly. If this doesnt do the trick, you may have a bad plug wire. Usually this occurs due to a pinhole in the insulation of the wire. Whenever the plug wire is energized, an arc jumps through the pinhole to the chassis of the vehicle. Replace with silicone resistor plug wires.
3. If the noise is a buzzing sound, the problem is usually associated with the points, distributor, or coil. Try replacing the condenser on both the coil and points. Make sure all plug wires are seated properly in the distributor cap. Additionally, you might try adding a 2200uF cap from the positive terminal on the coil to chassis ground.
4. Dont use the fuse block in the vehicle to derive power for the source unit. Run the Constant Hot B+ (memory) wire directly to the batterys positive terminal.
5. If you still have noise, it could be occurring because of induction. Try pulling the source unit out of the dash and check for noise. If the noise is eliminated, try rerouting any wiring harnesses that are close to the deck. If this is not possible, try using self adhesive metal shielding. This might just do the trick.

Turn On/Off Thump

Turn on thump can vary from a slight pop to a mind shattering, teeth rattling BOOM! This thump is caused by the audio circuitry stabilizing when power is applied. Most amplifiers and source units have muting circuitry that lasts a couple of seconds to allow these fluctuations to subside before passing a signal. However, if the amplifier un-mutes before the source unit or any other accessory, you better watch out. Here are some things to try if you have turn on thump.

1. Verify that the amp has a good audio ground reference. (See rule 6 of the Ten Commandments of noise free installation.)
2. Dont install the system so the amplifiers can be switched on when the source unit is turned off.
3. If you still have thump, add a turn on delay module in line with the remote turn on wire to the amp.
4. This concludes the section on turn on thump.

System Hiss

Hiss is usually most noticeable over the midrange and tweeters. The reasons for this are simple. The human ear is more sensitive to the frequencies reproduced by these drivers. Mids and tweets are usually far more efficient than their low frequency counterparts. And, these drivers are usually mounted closer to the listener. If you have hiss, you probably have your levels set improperly. Seerule 9 of the Ten Commandments of noise free installation.

While I know that I havent covered all the forms of noise or even all of the methods of dealing with it, I hope that Ive made a good start. By adhering to the Ten Commandments and investing a little persistence, you will be rewarded with a noise free installation.

[BigManAC]

I tried grounding the rca- didn't work. I tried new RCA's- didn't work. I ran all the wires on the outside if the car and and used the same + and - I use for the SQ2200 and that didn't work. I even hooked up my SQ2200 to the rear RCA's (same I was using for the SSL) and that sounded perfect. After all that I could not figure out why I still had engine noise. I finally figured it out though, it's a 12v amp and isn't capable of running at 14.8v

[BigManAC]

Thanks guys for all of the input! Stupid error on my part lol. I will deff keep all if these tips in mind if this should ever happen in the future.

[justin0943]

I never had a whine noise with my old amp which was an ssl the fury model

[ghostlyrich]

what happens if you pull the rear rca's pull the rear rca's out of the amp and plug them into the front? do you still get the noise ? if you pull the rear speeakers out and plugged them into to the front does it go away ??? if you do that and you still get wine it has something to do with amp or head unit other wise its front speaker and so on and so forth

*edit sorry didn't see it was fixed* ^^