SeaWeasel

I have a fairly straight-forward set up with a 6 channel amp running 2 pairs of components and a pair of 8ohm JBL 8's bridged to show the amp a 4ohm load mono on rear channels. I am running off a single "house" battery. I have been having some heat and voltage related problems- i.e., the amp gets hot and shuts down after about an hour and, on big bass hits, "clips out" due to insufficient voltage. With respect to heat, amp is under the rear bench and I usually run it with the seat up. I ran the wizz out of the same amp in another boat without subs and never had a heat or voltage problem, so I presume it is the bridged channels / subs causing the problem. Should I add another battery in series to help with voltage? Should I go to 4 ga power and ground (using 8ga now- run is less than 3 feet)? Should I add a fan? Any thoughts? Thanks.

ISurvivedNMU

I would try a larger ground.... Do you have a capacitor in there?

SonicBoom

I agree, larger wire. I have seen these fry in the past.

dlbCheckmate

What temp should the amp run at ? I have three Amps and the sub amp seems to get hotter then the others.

SeaWeasel

No capacitor. As I understand it, capcitors work by storing juice off of the alternator- i.e, if the motors aren't running the capcitor does no good once it is discharged because it will not be charged back up. The amp I am running has 8 gauge inputs, so I suppose I could run the 4 gauge to a junction block and then go to the 8 for a very short (like 6 inches) run? I think the sub amp gets hotter for a number of reasons, not the least of which is that it is probably high current / low resistance (like 2 ohm or below). It is also drawing a lot of voltage when you get a big sub hit (hence capacitors in cars with big amp / sub combinations).

deboatmon

Several things can cause overheating in your amp. Often overcurrent is the problem. That is- too much current for the wiring and supply and or output loading. As the requirements increase, with a setup like yours, the voltage can take big swings downward, thus causing the current to increase proportionally. To have a much better operating system adding more batteries would probably help immediately. Operating even a mid size system on one battery is probably not the best scenario. Up your main supply cable to #4 on both wires and add a battery in parallel, not series. Make sure your amp has a means to move some amount of air over and or around it for minimal convection cooling. Make sure you have all speakers phased properly. Out of phase operation might cause you to turn up the volume to compensate for the out of phase condition thus causing even more heat. Run your bridged loads at 8 ohms if possible. Doing these things should help the sonic quality as well as help to operate at cooler temperatures.

Good luck.

BadDog

I have a similar situation, two deep cycles with head unit, amp, hard drive based mp3 player and a refrigerator. My alternator has been upgraded to a 135 but I have killed both batteries. I want to add a small third for starting. If both deep cycles were fresh brand new off the shelf could I wire those in parallel on position 2 of the switch and the small starting battery on position #1? The number two position would be for on anchor and 1 for starting. Since it is a one wire alt I can safely switch to 2 for charging the parallel batteries. I had a Suburban that had both batteries hard wired together in parallel and ran it for years with not trouble.

I had always thought it was not correct to leave two batteries hard wired together but it worked fine for years on the Burb. Maybe because they were both new and always saw the same load and charge? I know I could wire it proper with another switch but it would be a lot more wire and hard to explain to the wife how the switches work. A 1 2 switch seems easiest.

Tim T.

HeavyChevSS

"What temp should the amp run at ? I have three Amps and the sub amp seems to get hotter then the others."<<<<<<<<<<<<
Bass takes the most energy to produce and the sub amp would see the most load. You should run the shortest, largest wires you can for power and ground and if battery won't handle the load I would run them in parallel and add a full size starting battery for the engine not a small battery unless you are starting a small engine...?

Outdrive1

I Would Agree, The Bigger The Power Wire And The Higher The Ohm Load The Longer Your Amp Will Play And The Better The System Will Sound. Try Running Your 4 Guage Power Wire To A Good Set Of Batteries (prefferably Optimas) And Running Your Subs Stereo At 8 Ohms. Having The Amp Under Under The Seat Without Any Good Air-flow Isn't The Greatest Idea Either. You Can Install A Small Fan (like The One In A Your Computer Case) With A Relay That Turns It On Off, Off Your Remote Turn On Or You Could Install A Switch In Your Dash. The Fans Are Very Inexpensive And A Relay Is Also Only A Couple Bucks. I Run Two 800 Watt Four Channel Fosgate Amps To My Mids And A 1500 Watt Fosgate Mono Amp To My Subs. I Have A Four Optima Yellow Tops That I Charge With A Battery Tender Because The 60 Amp Mercury Alternator Cant Get Close To Charging Those Batteries Running Around The Lake. I Run Two Batteries Parallel To Each Side Of The Perco Switch With O Guage Wire, Two Of The Batteries Run My Sub Amp With A 200 Amp Circuit Breaker And The Other Two Run My Midrange Amps With 150 Amp Circuit Brakers On Each One. I Run O Guage Wire For Everything And My Amps Are Bolted To The Back Of The Rear Seat With A Plexiglass Enclosure And Fans. When Its 115 Degrees Here At Lake Havasu They Still Over Heat After An Hour Of Play (at Very High Volumes). But At A Normal Listening Volume I Can Listen To Them From Sunrise To Sunset. You Cant Spend Too Much Money On Good Wire And Batteries, Its A Common Mistake. There Is No Such Thing As Overkill.