Questioni have had an aftermarket stereo for some time now (headunit, 2x12" subs, 2 channel amp for subs, 4channel amp for doors and rears which are aftermarket, and a capacitor for each amp) and have never had a whine. well yesterday i installed a sony xec-1000 Electronic crossover and now i have a hum/buzz/whine from my doors and rears. I was wondering is this whine caused from the fact that i have my amps and crossover running to the same ground. i had both amps grounded together and never had a problem because they are the same basic design. My capactiors each have their own ground. i know that it has to be something with the Xec-1000, but i wanted to get some advice before i rip out my interior again to get a good ground if i dont have to.
Answer "I was wondering is this whine caused from the fact that i have my amps and crossover running to the same ground."
It is possible.
Keep in mind that ground wires should be oversized (diameter) and as short as possible. They should also be attached securely to a paint free point on the chassis.
The ground of the vehicle chassis should be pretty stable, but I have no idea what year vehicle you are in. In older vehicles, chassis grounds can become more problematic.
Keep in mind that it may be a poor RCA cable ground.
If your amps are very close to the crossover, their ground point should be ok, if it is securely fastened.
Nine out of ten times, people just have the crossover and amp levels set too high which can amplify noise more than signifigantly. They presume they have a noise problem when actually they are just hearing it because the gain of the system is too high.
The #1 reason/desire for high output RCA signal from a deck is to avoid this issue.
I would start by reducing the levels to be sure they are correctly set and go from there if you still have noise.
Setting gains too high will NOT give you one additional watt of power!! It only leads to problems of this kind (and much, much worse).
My guess it that it's coming in thru the deck and you are only hearing it from the mids/highs due to the frequency of the noise (pretty much shunted from the sub if it has a crossover on its' amp).
I presume that you disabled all of the internal amp crossover settings when you added the new(?) sony. : Do so.
Check all of the system grounds from the deck to the amps.
You should try setting the amp levels at 100%, then use the crossover to set their actual gains. If it has input level trims, set them as low as possible (probably in a range of 20-45%) while still giving you enough signal at the outputs of the crossover to feed the amps enough signal to attain RMS power.
You should then be able to attain RMS power at each amp when the deck volume reaches 90-100%. That is the whole idea about gain and (most of) why setting up crossovers is the most important step of the install.
Lastly, you could try a ground line loop isolator (by PAC) if all else fails.
DO use one ground point for the amps and caps, if possible
I hope this gives you some resolutions.
Jmael
