equipment used:
Pioneer DEH-6800MP
-Full Range output to Rockford Fosgate p200-2
-Alpine MRD-m501(for two type R's)

wiring:
IXOS shielded RCAs
18awg Speaker Wire

Running:
2 Alpine Type r 6.5" component and tweeters (with included crossover)
2 Alpine Type r 6.5" coaxials in the back
(wired parallel from amp to crossover and continued to rear speakers for 100watts a side, amp seeing a 2ohm load per channel)

4awg power wire ran underneath car above frame rail, away from everything.

Passenger side:
Rcas for alpine mrd-m501
Remote for m501
right channel speaker wire

Driver Side:
Rcas for p200-2
Remote for p200-2
left channel speaker wire

okay now that you know what i'm working with. serious noise heard through my door speakers and tweeters when the blazer's running, engine on or not, still serious noise (like whistling)(ruling out alternator whine as a culprit). below is what i've tested, and still came up short on.

tested:
-removed HU, redid all connections with crimps
-removed rcas from HU to see if the sound persisted. it did
-disconnected rear speakers. sound still there, just all up front.
-removed rcas completely from amp, no whistle, still static.
-tested ground point with... a ground tester, perfect grounding.

Still coming up short. really lost here.

 

Could be a number of things, did you run the rcas under the door sill trim? happen to pinch it when you snapped them down?

Are you positive the ground is sufficient? where do you have it grounded?

Usually when noise is heard from a pioneer unit it's usually the pico fuse is blown from people hot-swapping RCA's while the unit is on, but you said the noise doesn't change when you unplug them.


I would venture to say you have defective RCA's, and/or bad ground

 

If I'm thinking of the right noise it would change pitch when the engine is reved up and from what I've heard some people say is thatits the RCAs picking up frequencies and you can get a special set of RCAs that have a ground wire running through them and that is saposed to solve the problem

 

-01vortec

to explain my ground spot, if you put down the driver side rear seat, the flap that folds down with the seat, lift that up. the bolts that hold that flap. i dremelled every last bit of paint off both sides and put both ground wires on the both and tightened the nut back down. i used a ground tester, and it glowed with grounded goodness.

i had a previous set of rcas running to my alpine mrd-m501 for the subs, so i moved those from the alpine to the rockford i'm having trouble with, i still had the same outcome

also, remember i said, with NO rcas connected to the amp at all, i got static. is that normal?

 

the set of rcas i'm running are ixos shielded rcas. they have the remote wire between the two cables. so (left channel/remote/right channel) all in one the part wire.

and yes when i rev the engine, i get more whining. i have the noise when the car is on but the engine is off too. it just gets worse when my engines on. but it's there as long as my deck is on.

 

try grounding it to the seat bolt instead of the flap that folds down.

 

naw, it's not my ground tho, because i used the same ground on the alpine amp, i've had the alpine amp installed like 5 months ago. and the ground was always perfect. subs at full power, bass **** all the way up, amp at full power, no unwanted frequencies came through at all. the ground tester shows that bolt being the best ground spot i could find.

 

Check and see if you have any kind of a hot wire running close to your rcas because the rcas might be picking up a frquency from being close to the hot wire if there is a draw from the batt

 

please read my original post, my 4awg power wire is ran between the chassis and the frame. underneath, coming up under the rear passenger seat. the alpine and the rockford are both running off that one wire and split. the only area where they would be near each other is maybe 2 ft underneath the seat before they're ran into the amps that are mounted vertically on the back of my subwoofer box. between the back of the seat and the back of the box. hidden.

 

just because you had the one amp grounded there doesn't mean it sufficient enough for two amps.