High pitch noise when iphone / ipod is connected

[hyphen79]

Got an interesting one for you guys.
Hooked the boat up to the fake-a-lake to prepare for the first trip out this season. While doing so I thought I would take advantage of being able to listen to my stereo.

Crank the boat, turn the radio on, and I start listening to a local radio station while I start to clean the interior of the boat, no high pitch noise (hasn't presented itself yet). Realized I had my iphone in my pocket I hooked it up to the ipod / iphone adapter that I installed last summer. Instantly I heard a really HIGH pitched frequency. The iPod adapter connects to the satellite adapter. It's not a hum.

The adapter I have:


The box that my adapter is plugged into. I have it plugged into the Pass-Thru:


Things that I did / tried to kind of troubleshoot it a little bit.

My head unit is the Clarion CMD5.

- Upped the RPMs on the boat to see if the pitch would fluctuate. NOPE! The pitch of the noise was constant.
- Switched from my cranking battery to my deep cycle batter. High pitch noise is still there.
- Turn the boat off and the high pitch went away (radio is still on).
- Cranked the boat again, and played all the audio sources I have available (CD, local radio) No high pitch noise.

Not real sure what it might be, but I wonder if it has to do with the clarion sirius box, or maybe the head unit isn't grounded to the same ground as my amps and EQ, or maybe its my iphone. I am going to hook up my iphone to the EQ with an 1/4 inch to RCA adapter tomorrow to see if I get the same high pitch. This might be my workaround.

Thoughts... Ideas? Like I said it's a constant high pitch. It's not a hum like you would get if you had a bad ground, or were picking up engine noise.

[hyphen79]

Meant to include my stereo / amp setup.

Head unit has RCA(s) out to my EQ. The EQ feeds the 3 amps that I have. Exile Harpoon for the towers, Exile xi800.4 for my inboats, and a JL XD600.1 for the sub.

The power for the amps come off the common post of my battery switch. The ground is run to my house house battery.

[chpthril]

Take the SAT unit out of the loop by connecting the Ipod interface directly into the Head-units C-net port.

[hyphen79]

Update on this... Took the boat out tonight for a quick run. The high pitch noise actually increased with the RPMs of the boat, and only occurs when the boat is running.

Here are the things I checked to try and isolate the source when I got back to the house

Re-tightened the power and ground cable
Tried a different ground location for the EQ
Bypassed the EQ

The noise is still very audible even when the EQ Is turned off. Could my issue be because my power cable is coming right off of the common post on my battery switch? Prior to this upgrade I had the power cable running directly off of my house battery.

[shawndoggy]

is your headunit power coming from the same place as the rest of the stereo?

and have you tried a different ipod?

[chpthril]

I went back through your stereo thread, but couldn't quite find the answer. I' understanding fro this thread that your system has a multi-battery switch, correct? Does your boat have the Diode type Isolator that would have been installed as part of the Tige EIDB Dual Battery system?

It is crucial, regardless of the charging/battery scheme, that ALL stereo components reference the same battery source. Outside of gain hiss (gains to high), this is the single biggest cause of unwanted noise in a dual battery setup.

Since the noise is increasing with the engine speed, its safe to say, it could be AC ripple from the alt or other engine components. Do you have a schematic of how the entire system is wired. lets first make sure everything is wired correctly. next we need to find exactly where its entering the system. Since its present with the Ipod hooked to the C-net, tell us is could be entering in almost at any point along the signal path or the peripheral. The fact that it wasnt present with CD or tuner is strange.

When you bypassed the EQ, you went right from the H/U to the amp(s), right? And it was still there. What about taking the Ipod right to the EQ's input with a 3.5mm x RCA and take the head-unit and C-net out of the loop? Next, take the Ipod and same cable and go right to each amp and see if the noise is still there.

Once I got an idea of your charging and battery setup, I can answer the question about where the main B+ needs to be connected to.

[hyphen79]

Shawndoggy: I believe so yes.

CHP: I just have a battery switch no isolator. Also, the noise is present even without the ipod / iphone plugged in. I don't know why I didn't present itself the first time the other night.

When I get back from the lake this evening I will draw up a diagram of my wiring.

Heading out to the lake.

[hyphen79]

Ok, here is the wiring diagram. Enjoy!

[ChrisBarnes05-12-84]

I have no idea how to fix your problem, but that is one hell of a diagram you made. Just figured I Would give you some props on your diagram making.

[hyphen79]

I have no idea how to fix your problem, but that is one hell of a diagram you made. Just figured I Would give you some props on your diagram making.

Thanks!
I deal with graphics on a daily basis. I was going to use Vizio to make it a littler more professional, but I decided I could do it faster in photoshop.

[shawndoggy]

I would do three things:

1. Get a new power run for your acc switch from the power distro blocks for your amps (fuse it).***
2. Get a new power run for your HU from the power distro block for your amps (fuse it).
3. Ground your HU to the ground distro block for your amps.

*** if the acc switch is grounded (and it may be because it looks like it lights up), then that ground should also come from the amps' ground distro block.

[chpthril]

Ok, here is the wiring diagram. Enjoy!

I see 3 thing that need to be addressed:

1) the head-unit's yellow (either not shown in your diag or represented by red) MEM wire needs to share the same B+ source as the rest of the audio equipment. The head-units red remote turn-on wire is just a 12V turn-on signal and can come from any source under the helm.

2) your diag does not show where the EQ's B+ is terminating. it too, needs to share the same source as the head-unit. This can be at: post C of the switch, the distro block, or an amp's B+ terminal lug.

3) your ACC switch is turning on the EQ and the amps, as well as conencted to the amp turn-on wire coming from the head-unit. This has the switch putting 12V on a wire that is a 12V output once the head-unit is turned on. You need to have the head-unit turn the EQ and amps on via a relay thats energized by the blue wire off the head-unit. Your ACC switch needs to apply switched 12V to the head-units red turn-on wire mentioned above.

[hyphen79]

I see 3 thing that need to be addressed:

1) the head-unit's yellow (either not shown in your diag or represented by red) MEM wire needs to share the same B+ source as the rest of the audio equipment. The head-units red remote turn-on wire is just a 12V turn-on signal and can come from any source under the helm.

2) your diag does not show where the EQ's B+ is terminating. it too, needs to share the same source as the head-unit. This can be at: post C of the switch, the distro block, or an amp's B+ terminal lug.

3) your ACC switch is turning on the EQ and the amps, as well as conencted to the amp turn-on wire coming from the head-unit. This has the switch putting 12V on a wire that is a 12V output once the head-unit is turned on. You need to have the head-unit turn the EQ and amps on via a relay thats energized by the blue wire off the head-unit. Your ACC switch needs to apply switched 12V to the head-units red turn-on wire mentioned above.

1. I will be checking this out later this evening.

2. That aspect of my diagram was to small to view. So I just took an image of it.


3. The ACC switch actually turns everything on as it's hooked up to remote wire to the EQ, to the HU, and to the amps. I don't think I illustrated it properly in my diagram.

[philwsailz]

As CHP said, you have your power wiring coming from different points on the boat. They need to all be coming from the same place. Ideally your head unit and your EQ need to have their power wires run directly to either your amp distribution block or the power lugs on your largest amp. Put a different way: DO NOT use the factory power connections, (both B+ and ground)for head unit or the EQ. WIth the stereo wired the way yours is, you want to re-wire your power througha relay.

The reason that you have whine is due to the fact that there is a LOT of other gear sharing the power wiring in thd helm. The ground plane is at a different voltage from the amplifiers and the B+ wiring is at a different voltage.... Trust me, you probably can't measure it but it is. When you have voltage diffferences, your Shielded RCA cable(s) becomes more like an antenna and they will pick up all radioated noise, including fuel injection computer noise, Tige Touch noise, and ignition noise. Move the EQ and the head unit power wire from the electronics wiring under the dash and re-wire so that the E! and radio share the same power as the amps and your noisee will go away.

Here is a diagram. It is not exact to your situation, but close. Just wire the EQ in parallel with the radio and it will be correctly wired.

Phil
Kicker