headless
10+ year member
CarAudio.com Elite
I just spent over a month trying to track down a problem in my car involving my new 1500XXK sub amp. Any time the 1500xxk would play bass, i'd get nasty noise out of my front speakers - which were on a 4150xxk. The noise was directly related to the sub amp playing, and even with all output from my deck disabled to the front channels i could still hear it clearly. bzzt. bzzt. bzzzt bzzt bztt.
Thinking the new amp was at fault (my existing amp combo of a Punch 100IX and my 4150XXK had no noise) i sent it off for repairs - and got it back from AudioTekX after he said he couldn't figure out the source of the noise. I sent it off to DB-R and he said he could not reproduce the problem at all //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif
Well, i finally decided to pull everything out of my car and test each component individually. 2 days of ****ing around with things has revealed that all 3 sets of my stinger rca's are the problem.
I have a few nice rca cables i tested with in the house - no noise at all with those.
So, i pulled out the DVM. Taking 1 side of the rca pair, i probed both plugs' shields. On the shitty stinger cables, there is connectivity between both wires' shields. This is the interesting thing - on one side of the cable, touching the 2 plugs shields gives me 0.1 ohms resistance - the shield is basically connected RIGHT THERE. On the other side of the cable, touching both shields gives me 1.8 ohms of resistance.
Checking 'normally' touching matching plugs on opposite ends of the wire gives me 0.9 ohms resistance. So it appears that the ground/shields on these wires are connected on one side of the wires. If i touch both shields on the 'far' side, the connection appears to go all the way down the one wire and back up the other, giving me 1.8 ohms resistance (the sum of both wires).
Checking the other side, i have 0.1 ohms because the shields are essentially fused together there.
So after much testing, I realised that if the side of the rca's that reads 0.1 ohms across the 2 wires' grounds is plugged in my HU, and the high ohm reading side is plugged into my amp, i get no noise. Reverse the cable...****ing NOISE.
The shields on my other rca cables are totally independent per wire, and they have nowhere near 0.9 ohms resistance from one side to the other. ALL 3 of my stinger cables are like this. **** stinger rca cables. The funny thing is, my punch 100ix never had a problem with it.
Thinking the new amp was at fault (my existing amp combo of a Punch 100IX and my 4150XXK had no noise) i sent it off for repairs - and got it back from AudioTekX after he said he couldn't figure out the source of the noise. I sent it off to DB-R and he said he could not reproduce the problem at all //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif
Well, i finally decided to pull everything out of my car and test each component individually. 2 days of ****ing around with things has revealed that all 3 sets of my stinger rca's are the problem.
I have a few nice rca cables i tested with in the house - no noise at all with those.
So, i pulled out the DVM. Taking 1 side of the rca pair, i probed both plugs' shields. On the shitty stinger cables, there is connectivity between both wires' shields. This is the interesting thing - on one side of the cable, touching the 2 plugs shields gives me 0.1 ohms resistance - the shield is basically connected RIGHT THERE. On the other side of the cable, touching both shields gives me 1.8 ohms of resistance.
Checking 'normally' touching matching plugs on opposite ends of the wire gives me 0.9 ohms resistance. So it appears that the ground/shields on these wires are connected on one side of the wires. If i touch both shields on the 'far' side, the connection appears to go all the way down the one wire and back up the other, giving me 1.8 ohms resistance (the sum of both wires).
Checking the other side, i have 0.1 ohms because the shields are essentially fused together there.
So after much testing, I realised that if the side of the rca's that reads 0.1 ohms across the 2 wires' grounds is plugged in my HU, and the high ohm reading side is plugged into my amp, i get no noise. Reverse the cable...****ing NOISE.
The shields on my other rca cables are totally independent per wire, and they have nowhere near 0.9 ohms resistance from one side to the other. ALL 3 of my stinger cables are like this. **** stinger rca cables. The funny thing is, my punch 100ix never had a problem with it.
