I know you’re a marine electrical engineer, but I have a marine audio question and I’m not sure who to ask. If this is not your thing, I completely understand. If you have time, and you can answer my question, I would really appreciate it.
I have an old 1976 double decker party barge with the following audio system:
- Rockford Fosgate RFX9700CD head unit (40w x 4 peak, 17w x 4 RMS) mounted in the driver’s console
- Four Poly Planar MA 9060W box speakers (rated for 100w max, 60w RMS) mounted on underside of upper deck
- Premium 16 gauge marine-grade speaker wire
- All new tinned marine wiring throughout the whole boat (much of which came from your retail site)
- One Pyle PLMRBS8 powered subwoofer mounted under a seat
I completely restored this boat in the spring of 2010, and I installed all this stuff new out of the box at that time.
The problem I’m having is that the radio is cutting out a lot if the volume is turned up as loud as you would want it when people are dancing and having a good time. At normal volume levels, everything is fine, but as soon as we turn it up for a good dance song, it starts cutting out. Here’s the four possible reasons I thought of:
- Do I need more power for those 4 speakers? Could that be the problem?
- Could the head unit be getting too hot? There’s not really any ventilation in that center console, although the center console is usually mostly shaded from the sun by the upper deck.
- Could the fuses on the back of the head unit be going bad, or something like that?
- I thought maybe it could be a short in the ipod adapter wire, because when you more the wire around sometimes it seems to get a little better, so I ordered a new one of those today, just in case that’s the problem.
If you have a minute and can answer my question, I really would appreciate it. Thanks for all your help in the past.
The current draw of the radio is more than your marine electrical can handle; the louder the volume, the higher the draw, the more the voltage drops. When the voltage gets too low, the stereo shuts off. When the stereo shuts off, the voltage goes back up, and the stereo turns back on.
Run a separate, 12 awg power wire and ground for the stereo back to the battery (or boat battery switch and ground bus) with an in-line fuse at the + battery connection.
This will solve your problem.
Thank you very much. I hadn’t thought of this. If I may, I’d like to ask another question to be sure I know how to fix it the way you suggested.
The wiring that’s in place for the stereo is using the complete pontoon boat wiring harness from EzAcDc, running through one of your switch panels on the driver’s console, and then to your smart battery switch (2 battery system). All the grounds go to a ground bus. The wiring harness has an in-line fuse on it, but I think that’s for the whole harness, not specifically for the stereo.
Are you thinking that the power wire for the stereo (in the pontoon wiring harness) is too small? So I should just swap the power and ground wires for the stereo to larger wires, running the ground wire to the ground bus, and running the new power wire through the switch panel, then to a in-line fuse, and from there directly to the secondary battery’s positive terminal? This will bypass the smart battery charging system, but that’s fine with me if it will fix my problem.
Would anything change about your recommendations if I decide to put a 50×4 marine amplifier on the 4 speakers? I believe you are 100% correct about what my problem is; however, I also believe that the 4 Poly Planar speakers would sound better with additional power. Like I said, they are rated for 60 watts RMS, and they are only getting 17 watts RMS from the head unit.
Thanks again. You’re awesome.
Isolating the power and ground for the stereo will solve your problem. The 16AWG is adequate for a smaller stereo, but once you go larger, it is not enough.
I would run the power back to the battery switch and connect it to the same switch stud as your boat accessory harness. The 4′ of 2 AWG red from the switch to the battery will not effect the voltage drop. The ground can run back to the ground bus for the smart switch system.