2003 SANTE Winter Stereo Project

[aikenis]

Ok. It won't be long and I will not be riding for a couple of months. I want to add/improve my current stereo situation. I purchased my boat about 2 years ago without much stereo in it. I installed a Clarion CMD5 with remotes at driver and transom. I have 6 Kicker 100W speakers in the interior (stock and 2 not hooked up). I have a pair of Fusion T-Series Combos on the tower. I have a pair of Kicker Solo baric 10L5s in a customer box behind the drivers seat. Pushing this is a Kicker ZX650.4 and a Kicker ZX750.1. I currently have some alternator whine when the boat is idling and the stereo is on. I am not sure where I want to start improving. Any thoughts?

[bchesley]

RE: 2003 SANTE Winter Stereo Project

If you are getting feed back I would start with power and ground wires. Putting them all together from the same direct source like a distribution block will help a bunch. Also using a good twisted pair style RCAs too. I have been amazed at what good wire and layout will do for performance.

[EarmarkMarine]

aikenis,

As for improvements, it would be helpful if you provided some direction as to which areas you would like to see improvement.

Six in-boat speakers usually consume four amplifier channels so a dedicated tower amplifier might be in order.

Pertaining to the alternator whine. It's rare in a boat. Things are so simple. Here's a few issues to confirm or steps to take.

*Correcting overgained amplifier inputs could reduce the noise below audible levels but you shouldn't have it regarldess.
*The source electronics should be well grounded as close as possible to the ground terminal of your largest amplifier. Don't depend on the factory harness.
*If you have a dual battery system (and you should) both the source electronics and amplifiers should obtain power from the same battery which is always going to be the case if all electronics access the battery switch common post rather than going battery direct.
*Seldomly is RCA cable routing the culprit. But to isolate the RCA cable just run an external jumper RCA temporarily to the high-pass amplifier.
*Make sure that your battery(s) is fully charged before trying to diagnose your noise.
*If you only have noise on an iPod for example, then the iPod power source or supply would come into question. This can be a problem when using the 3.5mm headphone jack which has a single common ground versus isolated grounds.

Its a start. There's other things to check if the above doesn't produce a remedy.

David
Earmark Marine

[aikenis]

Thanks. I have dual Blue Top Optimas. They are hooked to a selector switch. I make sure to maintain their levels. I have my power and ground coming off of the main battery for the amps and it goes to a distribution block. The headunit gets power from the factory harness. The whine is present when not using the Ipod adapter as well as using the Ipod. I guess the first improvement I would like to see is being able to use all interior speakers. If I add an additional amp, will I need to change my alternator and add a cap?

[aikenis]

I know people don't prefer the CMD5 as a headunit, but I like the remote capabilities. Would an EQ help the sound quality? What about changing the interior speakers out to something different?

[EarmarkMarine]

aikenis,

Your amplifiers should NOT circumvent the Perko switch with power battery direct. That alone is enough to create the whine. Reground the source unit to the amplifier ground.

A stiffening capacitor is pretty much a waste on a boat plus it creates additional problems.

Before considering an alternator upgrade, install a 20 amp multi-stage dual bank charger and get on a charging regimen while in storage.

There's nothing wrong with a CMD5.

An EQ may very well help by providing more line level voltage and placing zone controls at your fingertips. An EQ or remote control line drivers would be my final component after all other components were set and only after I resolved the noise.

David
Earmark Marine

[Mikeski]

I second the - fix the whine before adding new components comment

My guess is that running the CMD5's power and ground to the same source power and ground as the amp will make the whine disappear (it worked on mine). The factory power and ground to the cmd5 is very messy and introduces noise. It's a cheap fix. Also easy to just run test wires then start the boat on a fake-a-lake to see if it's gone.

[2gofaster]

Aikenis, It helps to understand a little about power when working on projects like this. My business is mission critical telecommunications systems and power and ground are perimount. If you have grounds and/or power connected in different places, you will end up with components that are at different electrical potential. This causes reverses in power flow from the ground back into the power section when it should be the opposite direction. This reverse in power flow is small. When this happens, funny things happen. One of those things is hiss and/or noise. In no system can you ever get every component at the same electrical potential as all the others because of differences in conductor length, conductor size, etc. You will always have noise in an amplification system. But minimizing those differences in potential can be the difference between the noise being above the audible threshold or below. So a simple place to start would be to move all your source unit power and ground to the same place as all of your other components.

[EarmarkMarine]

Shane is definitely speaking the gospel on noise.

Even though an RCA shield may be 1000 ohms above true ground it can still be the least resistive path for a potential difference to flow. And now you've got an intended shield carrying a voltage that is modulated by the alternator output. It would be hard to find a more vulnerable area to induce noise. So it doesn't take much. That is why its so critically important to close that loop by having the source electronics reference the same point as the largest amplifier(s). Shane said you can't close off every potential difference to perfection (stereo to battery, battery to engine block mass, etc. etc.) and its absolutely true. But if your RCA is the only path that circumvents stereo battery to amplifier battery isolation then noise is guaranteed to find its way in. You've got to fix this issue for sure.

David
Earmark Marine