scratching, screeching sound Wife comes home, says something wrong with car stereo, I grab beer and go listen. At first everything sounded ok then this very loud scratching sound. Kind of like someone taking a tonearm and scratching it across a record. but its a lot louder than the music that is playing. No fuses being blown, no amps going into protection, nothing changed just this very loud screeching scratching sound. Even with the volume turned all the way down its still VERY loud. Any ideas where I should look?? Alpine 9805 HU Terk alpine XM tuner Fosgate Fanatic Q in Fornt doors Oz Audio 6x9 in rear deck Mtx 942 at 4 ohm bridged Eclipse 4 channel 1 Boston pro 12 inch sub
pinched or shorted rca cable, that would be my first check. But, first, pull the rca cables from the amps. does the problem stop? if so go through the wire runs. if not then look to grounded/shorted speaker wires. Hard to diagnose without the car in my shop!
ok viking ill pull the rcas off of each amp tomorrow and ill let you know what happens. thanks for the input.
technically if hes runnin his speaks off an amp and takes off the rcas thats wont really elimitate anything will it? no sound will come from them anyways, unless the speaks are picking up some sound, if its comeing from all speaks off a 4 channel amp and he has 2 sets of rcas run for them, one for the front one for the back, that makes me believe its either an amp or hu problem...
yuh but if all 4 of his speaks are doing that then it would mean either every single rca went at the SAME time, or its the amp having a bad ground picking up distortion or it could be his rca connectors at his hu or amp are bad. yes it sounds like an rca problem if it was soilated to one MAYBE 2 speakers (either both front or both rear), but for all 4 to go????
Its just a sarting point to determine which way to go to isolate the issue. And its an easy sarting point If the rca's are unplugged, and the problem goes away, then plug them back in one at a time to see which one(s) are the problem. If the noise still persists with them unplugged, its an amp/speaker issue. I am willing to bet once theyare unplugged the noise will subside. Next step would be to unplug them from the head unit and see what happens. Its just a process of elemination
After listening to it more today its more of a loud popping sound. I unplugged the rcas from the eclipse and still there then went to the mtx and unplugged those and the problem went away. Rechecked all the grounds, all nice and tight. Pulled the car apart and checked the rcas and seemed fine. No kinks or binds and the insulation is good. Any other ideas?
Ok eclipse = HU right? MTX= amp???? right? IAre you using an external x-over? Also, are you using more than 1 amp? layout your sytem in detail please. Oh, and are you usinfg any passive x-overs? need more info to trouble shoot
System in detail Alpine 9805 HU Terk xm alpine tuner Eclipse 4 channel amp pushing Fosgate fanatics in front doors and Oz audio 6x9 in rear deck. Mtx 942 amp mono bridged pushing 1 12 inch Boston pro sub at 4 ohms No external xovers just using the ones on the amps using 1 awg wire to distribution block, then 1 awg to mtx and 4 awg to eclipse. The big 3 have 4 awg already installed. 130 amp stock alternator. 10 awg speaker wire throughout the car. Stinger rcas and stinger pro battery terminals. With car at idle i get 14.1 volts at battery and reading 14.08 at input of mtx and 14.0 even at eclipse. Of course they go up or down depending on music passages and the rpms of the car. So I know the mtx is getting good voltage and its not going into protection. So im at a loss, any ideas of what would cause the VERY loud popping sound, even with the volume all the way down.
