Do I need another battery for my speakers

I am going to be installing about 150w (300w total) speakers into my boat. I am going to use about a 400-500w amp. Do you think I will need another battery in my malibu response? Also, is 400w too big of an amp size?

Get a second battery no matter what, cheap insurance to not lose a day (or a minute) on the water. First thing I always add to a boat.

Amps are never to big! Actually that's a complex question. What are you driving with the amp? How is it wired? What are you trying to acheive? Every time I ask an amp question I get these type questions back. There is no easy answers in audio world except more speakers and bigger amps is a good thing

I second Bill, add the battery regardless. You'll start with 1 400 watt amp and end up w/ 1800 watts of amps You'll need the 2nd battery sooner of later

It depends on how you listen to your music. The ONLY thing a battery will do is increase your key-off play time, so if you only really listen to music with the engine running (while driving or riding), then a second battery won't do anything for you.

if one were to add the second battery, should you get the perko switch or just hook up the stereo to it and nothing else?

perko or isolator/relay

I wont be playing music when the boat isn't running...so I dont think I need a 2nd battery.

I would say at least carry a jumper box on the boat if installing a second battery is not an option.

I think everyone should put a battery swtich and a second battery in their boat, it's less than $150 and a few hours work but you then have total confidence that you can disconnect everything from the battery with the switch as well as have a second battery in an environment that is hostile on batteries. That's my opinion and the first thing I've done to every boat I've bought.

You dont listen to music with the motor of so it's not that big of a deal, but if you ever do, being able to isolate the drain to one battery and just laugh when it goes dead after the music has cranked for a few hours is priceless. Then you start up on the other battery! It's a really weird feeling of absolute control

Ok, I am going to be getting 4 250w (65w RMS) sony speakers. What size amp should I get?

(Monstertower)I know this is going to be a dumb question

So when you add a second battery how do you wire it so that it is being charged when the boat is running yet it is not being drain by playing the Radio with the boat off.

Also
What is a Perko?

Last weekend I was in the boat playing the radio thinking to myself how long can I play the radio before the battery goes dead, ( knowing that I forgot my Jumper Box at the house)

Well, the guy who works on my boat said my altenator will not keep up, so I will be buying another battery. He says I need a deep cycle, any suggestions?

Yes, you want a deep cycle, but a second battery won't do anything if your alt can't keep up. If you're not putting out enough amps, the only thing the second battery will do is create more work for your already over-stressed alt.

If your amp is putting out 400-500W RMS to full range speakers (meaning no sub), and that's all the electrical accessories you're running you shouldn't have any problems with the stock charging system.

Whether or not you should add as second battery depends on how often you listen to the stereo without the key on. The second battery is just a reserve, so the only time it will help is when your charging system is not providing positive current and you're using electrical accessories.

Leo, who works on your boat? How big is your alt? It should be at least 50amps? My mechanic knows baot mechanics but doesn't knwo much about stereo equipment. You alt shouls have no problem keeping up wiht just one amp. What other acc. are you running in your boat.

Chris, Do a search for perko and isolator/relay, there tons of info on it. they are both very easy to hook up. Both come with instructions. A novice can do it

Ok, I am not sure how big my altenator is. It is a 365hp inboard engine so i can't imagine it would be small. I will not be playing the stereo with the boat is turned off. The guy who works on my boat might just be trying to get my money???


I almost forgot to mention... we dont really use any other appliances while we will be listening to music. The only other time is when we fill the fat sacs...we just wont play the speakers and fill the fat sacs at the same time, simple.
We barely turn the boat off when we go out, and we barely use the speakers except through the no wake zone. Now that I am buying tower speakers, I will be using them while I ride. The amp will only be pushing about 300W RMS (75w per channel/4 channels).

Please help anyone...Thanks for your help Jason and Adam.

(Message edited by malibuboarder75 on February 17, 2005)

Leo, you're just fine with the stock charing system. Your Response with the Hammerhead has a 70A alt stock, which will be more than adequate for the amp you're planning on running.

If you do decide to add more electrical accessories down the road though, just be sure you don't neglect your charging system.

Enjoy the new tower speakers!

Jason, you are big help man. You don't know how clueless I am with this stuff.

Next question: What gauge wire should I use with an 800w amp (75w RMS/ 4 channels) to the battery? Also, what gauge wire should I use for the speakers? My guess was 8 gauge for the amp and 14 gauge for the speakers. Should I go with 4 gauge for the amp?

Since the install is going in a Response, I'll assume the amps will be right next to the battery under the dash. If that's the case spring for 4 gauge. The runs won't be longer than a few feet, so cost wise it doesm't make sense to use anything larger.

14AWG is just fine for the speakers.

Correct Jason...Thanks.

Any suggestions on an amp? Do amps do bad in moist atmospheres? Should I get a cheap one since they wont last?

Leo, I have VLX with stock Alt, 3 batteries on pergo switch , 2800W system and it runs good.

Leo, water is bad for amps, but being around a boat, as long as you allow things to dry out when you're done riding isn't TOO tough on an amp. You're better of spending enough money to get something that is higher quality because your speakers will sound better, and you'll be less likely to damage them.

JT, that's WAY too much draw on your stock alt. Unless your dealer spec'd the obscure 90A upgrade on your boat as part of the "heavy duty wiring package" your alt can put out a maximum of approx. 1500W at full RPM. It looks like you've got some 800.4s and a 700.5 which are well over the total current consumption level for your charging system.

Quite frankly, I'm surprised you haven't run into problems yet.

Jason, I don't care too much about sound quality. I just want to hear the music 75ft behind my response. I dont want to hear static, but I at least want to hear the music. I don't want opera quality, just listening while riding quality. If that makes sense.

JT, I'm also surprised you haven't had any low voltage issues? what voltage range are you in while running/motor off?

Leo, it may be hard to really "hear" the music @ 75' w/ only 4 6.5's in can's? IF they can only handle 65watts RMS, you'll probably be pushing them pretty hard to barley hear them while riding, and end up blowing them. I've run a similar set up and exp. the same thing.

They are 65 rms but 250w peak, so I don't think I will blow them...

so were mine...I think peak was around 225. Peak is not a very good indicator of power handling. Peaks occcur in very small bursts. I smoked a set of pro audio fosgate components, I foget which model, the one up from the stuff they sell at best buy, ect. When I mean smoked...literly melted the crossover, and blew the tweeter. Basically trying to get to much out of something that couldn't produce what I wanted. Learn from my mistakes , if you truley want sound to the rider look at the NVS or new skylons. Well worth the price.I spent thousands $ on tower setups trying to find somehting I liked...would have been alot cheaper to have bought the NVS from the beginining. Next best thing is a 4 or 6 6x9 setup. Good luck!

Ok, I talked to my mechanic and he said that the altenator will keep up, but I need a second battery to increase the voltage. Is the second battery really needed for the voltage, or is it just a backup as many of you have suggested



...on another note. I am thinking about getting a audiobahn, JL, or Jensen Amp. I can get one for a really good price on ebay (I will be spending a little more, but I think its worth it).

jensen is crap. I have audiobahn amps, been pleased with them. they are better than jensen. Not the best but I feel great for the price. JL is definately the best, but you'll pay for it. Adding another battery will not increase your voltage.(unless you wire in series (24V), but DO NOT DO THIS!!MASSIVE F.U.B.A.R!!)go to a local stereo shop for your stereo questions and leave your mechanical questions to your mechanic.

If I were to hook up two batteries to a perko switch, would both batteries need to be the same kind? Right now I just have a regular marine battery in my boat. Could I buy a blue top and hook that and my regular battery up to a perko switch and have it work ok? Thanks.

Good question Justin.

I have a KX800.4 and a KX750.5 with dual batteries and we worked the amps hard and never had a problem with a factory alternator. I expect if we had one battery the chance of losing riding time to a dead battery would have been greatly increased.

I'm running two 800.4's and 1200W mono that power 4-10's. All kicker stuff. My wife used to work at SPY and they have deal with Kicker. I paid about $1300 or so for 2 - 800.4W , 1 - 1200W mono , 4 - 10's, and 3 sets of 6.5's for inside of boat. Then we run Defcon 3's on tower. With stock Alt, we have 03 VLX and system has been in boat for two years. Both batteries don't need to be same unless your running 3 and the two together need to be new and the same.........at least that what I was told.

P.S.

You cant get anything louder than 6 x 9's, my last boat had 4 - 6X9's on tower and was way louder than the set up I have now. Plus they are cheap if they blow.

The thing that is important to remember is that a second battery will only help you if you have enough current to charge it. If your charging system is over-worked and can't keep up, there is no way it will be able to charge the second battery. There's no ranking system, so while your boat may still run, if the amps are pulling more current than the alt can put out, the engine is deprived just as much as the electrical accessories.

As for the output of 6x9's, the Deafcon IV and V will absolutely destroy any traditional car audio speaker, regardless of size

Well, if the 4 6.5s don't work out, maybe I can add 2 6x9s plus a 400w amp. It sounds like 6x9s are the way to go. I made a lot of money cutting grass this week so I can spend a little more than I intended. I am going to go with the audiobahn a6004t for the 4 6.5s. After I install those, I will see what works best and maybe purchase the 6x9s if it isn't loud enough.