Help I have a whine noise in my speakers!
Updated: Apr 10, 2020
So I get this question posted several times a month in the group www.facebook.com/groups/caraudioinstall and I realized that I do not always put forth the effort to type out a great response every single time so this is going to be a better way to explain. Here is the issue that happens a lot when someone says "Help I have a whining noise in my speakers!" So a whining noise is usually coming from a few possible things. Usually you will hear the whine coming through your tweeters and front speakers. It is usually high pitched and changes pitch with the engines RPMS. This is commonly (and sometimes incorrectly) referred to as a ground loop. Here are a few common things you can do to try and fix the whine noise: - Check your RCAs. Check them by doing this first, unplug your rcas and see if the whine goes away. If it does then it is safe to say that the RCA are somehow introducing the whine. - Check your RCAs even more. Did you run them next to a power wire? If so then it is likely that the RCAs are picking up some electromagnetic interference (EMI) from the power wire. This is normal and happens sometimes which is why it is a common rule to run your RCAs away from the power wire. What happens is the power wire becomes somewhat electrically noisey and it radiates some of that noise as a magnetic field. Since your rcas are a very low voltage then sometimes the EMI will bleed into the rcas if they are too close and then that EMI will also be at a low voltage that the amp has a difficult time ignoring while it amplifies the audio signal. - Next step if you do have some EMI in your signal and it is very slight: Turn your gains down. The amplifier is working hard to amplify the signal and if you have your gains turned too high it will amplify the EMI as well as the signal. By turning your gains down you will be forced to raise the volume on the stereo to get the same sound (hopefully without the whine). But when you raise the volume on the stereo you are also raising the signal voltage which will make it higher than the small amount of EMI on the signal lines. So by doing so you separate the signal from the EMI so when the amplifier does it job it is not amping the small amount of EMI as well. If you can get this signal further away from the EMI then you will hear less of it after the amp makes all the signal on the lines louder. This is where higher preamp voltage is beneficial, say 4v preouts vs 2v. - Now is the part I actually wrote this blog about. I usually also recommend running a Reference ground with your remote turn on wire on ALL 4ch (or full range) amplifier installs. Most people have never heard of a reference ground so I will first explain how you do it, and then why you do it. A reference ground is an EXTRA wire that connects the head units ground and the amps ground together. It does NOT replace the grounds, it only ties them together. So leave the headunit ground hookedup, and leave the amps ground hooked up, but run an additional wire between the two to link them. So WHY? I know this is the big question. The reason you run a reference ground is because electricity always travels the path of least resistance (first). So sometimes what happens when the amp or headunit doesnt have the best ground possible is that it will search for the best ground possible. And sometimes if the best ground exists on the other end of the RCAs it will actually try to ground through the RCA shielding. This can also cause EMI noise because now you have DC current flowing through the RCAs at an incredibly close proximity to the signal. So by running that reference ground you are providing a better ground than the RCAs shielding, a ground that has less resistance so the ground path through the RCA shielding will hopefully be lessened. This should reduce the amount of EMI you would get if this was in fact the issue. so as a recap, and BTW please notice i did NOT mention the standard internet car audio forum response of "your pico fuse blah blah". Yes you can blow your pico fuse if you do not run a reference ground first! So as a recap, if you have engine noise out of your full range amp. - unplug the RCA, does it go away? - Run a reference ground (on every full range amp install) - Separate your signal wire from your power wire
- Turn your gains down to where they should be A few things I did not mention: - if you have a bad battery this can cause some of the issues. A battery should filter some of the AC Ripple the alternator makes, so if the batteries going bad it will have less filtering capabilities. - if you run a hot rod with a souped up ignition, MSD or some other HEI system, then they make filters for that stuff because it is super common for those ignition systems to be noisey and cause this as well. - could simply be a bad amp ground. If you ground your amps with my zinc grounding lugs, you will likely NOT have that problem. Also check your batteries ground, very important. A big three upgrade would help solve his problem. Last but not least if this still does not fix the issue you can look into grounding the back of your pioneer rcas sheilding if you blew the pico fuse, try a ground loop isolator to filter the sound out of the signal or try a power filter. https://www.franksaudiomotive.com/product-page/ax-anr1000-noise-supression-filter You can find the zinc grounding lugs here: https://www.franksaudiomotive.com/product-page/zinc-thread-cutting-ground-bolt You can buy the gound loop isolators from me as well: https://www.franksaudiomotive.com/product-page/ax-agl610-rca-ground-loop-isolator And some 16g primary wire to help with your reference ground install here: https://www.franksaudiomotive.com/amplifiers-wiring?Collection=Primary%20Wire