why is the amp making the speakers making a buzzing sound ONLY when car is ON?
well everybody, it finally hit me that i don't need 2 competition 12 inch subwoofers in my 73 mach 1 that weight 20lbs each and with the box it weights roughly 90lbs. (sure it did slow me down). so i took out those subs and i hooked up the door speakers and the rear speakers to the same amp i had pushing the subs. (kenwood 600watt 100watts x 2) all the speakers are 40rms watts so it's a perfect size amp to push all 4 speakers.
when i was done and i turned on the music. i couldn't believe my ears, the sound was so clear. it was LOUD and CLEAR to be exact. i asked myself why i didn't just do this from the beginning. i also have 2 speakers in the dash board. with 2 speakers in the dash, 2 in the doors, 2 in the rear, it makes the car sound awesome.
but then, i wanted to take it out driving to listen to the radio i heard a buzzing sound. that buzzing sound is coming from all 4 speakers connected to the amp. i made sure it was the speakers by putting my head right next to all 4 speakers. i turn down the volume to "0" and the same buzzing sound stays there. the buzzing sound DOESN'T change volume though. at 0 volume you hear it the most, but at 1/2 volume you don't hear it anymore. anything above 0 and below 1/2, the buzzing sound goes down. it's only because the music volume is louder so it cancels out the buzzing sound. but you can still hear it at the same volume at voume 15.
however if you turn off the car, the buzzing sound goes away. start the car right back up, the buzzing comes back. turn off the car, the buzzing goes away.
i then looked at the amplifier. there is a switch that says "stereo or mono", knowing it's for 4 speakers i put it to "stereo", and there is a filter switch, saying "off or lpf". low freq, means bass as in short. i put it on "off" because i do not want the speakers on the low freq. side. if you do all you hear is bass out of the speakers. if you put it on "off" you hear the buzzing sound. if you switch it to "lpf", the buzzing stops.
what in the hell can cause this? i hear it could be the condensor in the dizzy can do it, or spark plug wires. but it never did this to my subs when i had them hooked up. what else can cause radio interference. if it's something under my hood. it's funny because it didn't do it when i used my amp to 2 subs.
though i ALWAYS used this amp for subs. i haven't ever used them for speakers. people told me this specific amp is PERFECT for speakers and not for subs. thats what made me (part of ) hook the speakers up to the amp.