I have this weird problem that has me baffled. I have a polk momo mm2104dvc sub which was powered by my c300.2, no problems whatsoever. Ive recently acquired a c500.1 to power the sub. I did a straight swap between the amps and all is fine... When the headunit is on. When i turn the headunit off the sub makes a sound increasing in loudness ending in a extremely loud pop. This repeats continuously until i turn the headunit on. There doesnt need to be any music playing or any volume level set on the headunit. It simply needs to be ON. As soon as i turn it off the symptom reappears. Im using speaker level input as the stock headunit does not have a line out. The ground has been checked. The remote lead is connected to the vehicles accessory lead. I have swapped the amps back ie. Connected the c300.2 to the sub and i dont experience this. It only happens with the c500.1 Any suggestions/help would be highly appreciated as I am at my wits end.
I just copied this from another forum that I go on from time to time. I hope this will answer your question. 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 can't 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 doesn't 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 2200 uF cap from the positive terminal on the coil to chassis ground. 4. Don't use the fuse block in the vehicle to derive power for the source unit. Run the Constant Hot B+ (memory) wire directly to the battery's 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. Don't 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. See rule 9 of the Ten Commandments of noise free installation. While I know that I haven't covered all the forms of noise or even all of the methods of dealing with it, I hope that I've made a good start. By adhering to the Ten Commandments and investing a little persistence, you will be rewarded with a noise free installation. Here's the link: http://www.icixsound.com/vb/showthread.php?t=47564&page=3&pp=10&highlight=amp+popping+noise
