need help with turn-on/-off pop & thump! i've tried everything!

[ahardy17 10+ year member]

i just finished installing a new box in my car, seen here: http://www.caraudio.com/forum/car-audio-build-logs-*new*/440304-two-memphis-m3-12s-mcd1-1100-first-ported-box-5-cubes-@-36hz.html

and i've got the worst turn-on/-off pop and thump i've ever heard in my life.

the amp remote wire on my HU's harness says "to amp remote in 0.3A max" and i have that going through the relay straight back to my sub amp then the second amp is piggybacked off of that one, with a short wire between the 2 amps. i've done that before with no problems.

i had a blue neon on the amp rack running on the same remote power but removing that didnt help.

i've tried using shorting plugs on the amps and theres no noise when i use those so i'm pretty sure it's not the amps.

i have the amps well grounded, theyre grounded about a foot apart from eachother with star washers under the ring terminals on clean bare metal

a loose power wire contacted my RCAs a while ago in the process of upgrading and i cut a couple inches off the ends and re-soldered the ends on. but i dont think thats the issue because i have one brand new set of RCAs and its the same with them

there's a fuse on the back of the HU and thats fine too

i'm at a loss here i've exhausted all my resources and searched old threads for answers to no avail.

i also upgraded my big 3 in the process and the new ground comes a tad closer to the power wire than the old one did, but i dont think that makes much difference, just giving the details so you guys know what the setup is like.

one other thing i did was eliminate the harness wiring for factory speakers because there was no room behind the HU. no clue what kind of effect that might have had but i thought it was harmless

any input would be greatly appreciated...this is driving me crazy

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[Chrispy 10+ year member]

New/Better ground. Do you have the amps grounded to the frame or just sheet metal?

 

[azphat12 10+ year member]

Run the turn/on lead direct to 1 amp. Then the other. This will tell you if its the relay, or 1 of the amps. Not saying an amp is bad, but atleast you would know if 1 amp or both did it with a direct feed.

Basic test, but will give you something to start with.

 

[I Like Waffle]

Your problem may be you have star washers UNDER the ring terminals, the ring terminals are supposed to be on straight metal, then a washer, then a bolt. Atleast in my book.

Try adding the relay to the acc wire on the radio to run your neons, and just using the rem wire for the amps. If its a pioneer radio you may have blown the pico fuse when that loose wire hit your RCAs. I did the same thing and had TERRIBLE turn on/off thump. Ground your RCA outputs to the back of the head unit, that may fix your problem.

 

[I Like Waffle]

Your problem may be you have star washers UNDER the ring terminals, the ring terminals are supposed to be on straight metal, then a washer, then a bolt. Atleast in my book.

Try adding the relay to the acc wire on the radio to run your neons, and just using the rem wire for the amps. If its a pioneer radio you may have blown the pico fuse when that loose wire hit your RCAs. I did the same thing and had TERRIBLE turn on/off thump. Ground your RCA outputs to the back of the head unit, that may fix your problem.

 

[Jh8909 10+ year member]

if not that check your headunit ground. thats where my pop noise was coming from, changed it to a new spot and it was gone.

 

[ahardy17 10+ year member]

New/Better ground. Do you have the amps grounded to the frame or just sheet metal?

i'm probably gonna try to ground them to the frame now. theyre on sheet metal currently.

Run the turn/on lead direct to 1 amp. Then the other. This will tell you if its the relay, or 1 of the amps. Not saying an amp is bad, but atleast you would know if 1 amp or both did it with a direct feed.Basic test, but will give you something to start with.

thats the first thing i'm gonna try when i go back out there, good idea, thanks. i will shoot myself if my memphis amp is ****ed tho...luckily i have a spare shitty amp for the mids

Your problem may be you have star washers UNDER the ring terminals, the ring terminals are supposed to be on straight metal, then a washer, then a bolt. Atleast in my book.
Try adding the relay to the acc wire on the radio to run your neons, and just using the rem wire for the amps. If its a pioneer radio you may have blown the pico fuse when that loose wire hit your RCAs. I did the same thing and had TERRIBLE turn on/off thump. Ground your RCA outputs to the back of the head unit, that may fix your problem.

sorry i meant to say the star washers are over the terminals, which are right on the metal. i'm gettting rid of the neon for now, i can do without that, but having my sound a mess is driving me crazy. how exactly do i ground the RCA outputs to the back of the HU?

if not that check your headunit ground. thats where my pop noise was coming from, changed it to a new spot and it was gone.

it currently uses the ground in the harness...i suppose a proper ground is in order...its all pretty ugly behind the HU so i might go straight to the battery with that one

 

[Jh8909 10+ year member]

yeah you might be better off that way.

 

[keep_hope_alive Premium Member]

how exactly do i ground the RCA outputs to the back of the HU?

it currently uses the ground in the harness...i suppose a proper ground is in order...its all pretty ugly behind the HU so i might go straight to the battery with that one

sometimes with Pioneer units you need to ground the RCA shield. you can do this in the RCA cable (if they don't have molded ends) or inside the unit.

Don't run a ground wire to the battery. clean up the wiring behind the HU, do it right - there may be something in that mess causing your problem. ground the HU to the floor - sanded bare metal.

 

[ahardy17 10+ year member]

thank you DrChronic! its a sony HU but evidently it was the same pico fuse problem thati hear so much about with pioneers. grounding the RCAs worked out real nice. now i can catch up on my hearing loss //content.invisioncic.com/y282845/emoticons/smokin.gif.f1dc8d2acb1809e863ebd6a47eaa0d45.gif