White noise in speakers..

[Bryan]

So recently I'm starting to get a hiss in my tower speakers only while the motor is running. When anchored and swimming all is good, but as soon as motor starts there's a hiss. Music will of course cover it, but while switching songs or muting to talk to riders, it's very noticeable. I use my iPhone plugged into a dock cable running to the head unit aux in, but the noise is there whether the phone is plugged or unplugged. Again, noise only while motor runs, and sometimes I get a whine sound when I adjust taps and sometimes I don't. I'm assuming I've got a ground issue, but wonder if anybody can narrow down where to start looking.. I've got a whole box full of nice new wiring and amp install components that I got from CHP, but I haven't touched anything yet so it's strange to me that is just randomly starting now..

[cpobanz]

My z3 has 4 amps and was doing the same thing, the stereo is grounded at the battery, and everything looked okay. I installed this filter and it all magically went away. My amps are daisy chained together, so I put the filter on the main rca coming out of the headunit and attached the brown wires to some screws on the headunit casing. It was an easy fix, and my noise was unbearable.


https://www.amazon.com/dp/B001EAWS3W...NCJ3M76N&psc=1

[cpobanz]

sorry wrong item in the first link I sent you.

https://www.amazon.com/PAC-SNI-1-Noi...o+noise+filter

[chpthril]

Barring an internal issue with an existing piece of equipment thats going to be retained, doing the rewire will likely resolve the issue without the use of a GLI band-aid. There will be some particular wiring that needs to be done as the rewire moves forward, but we can address those later.

For right now, id suggest we try to isolate the noise down to where its entering into the system. Is the noise linked to the engine RPM or just present when the engine is running? Is it audible from all speakers/all amps or just part of the system like left chnl or right chnl, front or rear, tower amp or in-boats amp, etc. Hiss can be excessive gain level, whine can be Ground loop issue. Interference from things like a TAPS motor, may require a CAP to be wired across the offending motors wires. A bad RCA can allow noise in, yet still pass signal. Periphirals like EQ, BTs, SAT and USB chargers can also create noise due to the wiring scheme.

Give us a rundown of the current gear, and whether its staying or going as the build progresses.

[Bryan]

I'm almost positive the rewire will solve the issue.. Just wasn't planning on doing it until business slows down in the fall. Had all intentions of doing it this spring when I ordered the stuff, but I got busy as crap and the rewire hit the back burner.. It's a mess in my amp locker. It's embarrassing to say the least. I don't know who installed all this stuff, but I've got 3 batteries and 2 amps and all associated wires all over the place.. RCAs have been split and passed through amps into other amps and left laying on power cables and all sorts of crap.. I'm thinking the best place to start looking for the hiss will be the RCA for the towers, as that's where I hear it. (It may also be in the in boats, but if it is I couldn't hear it.) I haven't traced all RCAs yet, but there are two sets into and tower ht4 and a set out and they're all electrical taped at the joints. Move one the wrong way and there's static.. (but sounds diff than the hiss) Is that bad amp inputs or bad RCA?

The sub and it's amp are all seperate for the time being so I don't see any of those pieces being the prob..

The only periphial in the boat is the usb charger that the phone plugs into. It's an APPLE piece that has the dock connector split into a 3.5 jack and a usb plug The 3.5 goes into RCAs into the aux in and the sub goes into a charger in the 12v socket next to the steering wheel.

Crap.. I was hoping this mess would get me through this summer and I could do this later... It's hot here...

[Bryan]

I lied.. I also have a wet sounds rgb music controller that's also split into my 3.5 coming from the iPhone, but it was there last year and there was no issues with noise caused by it..

[chpthril]

Well, its now in the signal path.

[Bryan]

Forgot to answer:
Noise is present while engine runs but doesn't seem to be based on RPM.. Stays constant
Gains on all three amps are under half.. And I keep the line out sensitivity setting on the head unit around 3 on a -6 to +6 scale..

[Surf406]

im gonna stalk this thread simply cuz ive been battling the same issue and im tired of it as well.

[jimidemo]

You said its just your tower speakers. Unplug the rca's from your tower amp and if the noise is gone move upstream. I played with engine noise all spring only to find out it was being introduced by my head unit. Thought it was the new amp I had put in....kept chasing my tail. Check all grounds....and re-check till it hurts. I know your frustration first hand!!

[Bryan]

Update...
Went out today to get the wife a few pulls and I unhooked all periphial crap from my aux in line.. Strictly signal from iPhone now.. No change. Messed with head unit and noise is there no matter what source I have selected, so I think that knocks out the aux-in side of things.

I did notice today that when switching the battery switch, I caught a thud in the tower speakers..

Taps whine through speakers was about 50% of the time. Could find no rhyme or reason as to what was causing it or stopping it. Has to be a loose wire right? Makes good contact sometimes then hit a wave and it changes?

I've been outside now for the last hour checking all connections on all three batteries and replacing all the RCAs with the new stuff I got from CHP.. Bad part is I can only recreate the hiss with the engine running so it's gonna be Friday now before I can see if that made a difference... Side note: Sounds great sitting outside, I'm sure the neighbors love me

[Bryan]

Well... I just don't know. Replaced all RCAs and checked all grounds and its was a bit better today, but worse at the same time. No more taps whine through the speakers when I move the plate so that's good I guess. I think its probly in the RCA outs on my headunit. When I unplug them the sound stops, didn't seem to matter which I unplugged, it killed the noise. Even just moving them around a little would help. Also, now my in boats seem to be phasing left and right sometimes. Again, that's gotta be RCA related right? The cables are new so it has to be the stereo out.. Would it do me any good to run the black headunit ground straight down the the battery? It disappears into the wiring harness to end up God knows where... Might that kill my dreaded hisssssssssssssssssss

[chpthril]

Im going to email you some isolation steps and some wiring tips sometime this weekend.

[Bryan]

^^^