What batteries for stereo, and install help?

I am doing my stereo this weekend and I need to know what batteries to hook up and how. My R20 came with an interstate deep cycle battery, and I have a switch already installed by no second battery.

My stereo set up is an Alpine PDX5 running 6 interior wetsound 6.5s, and a 12 inch JLw3. I have an Alpine PDX4.150 running two Rev10s on the tower.

So what battery do I get for the stereo and how do I hook it up with the switch? On my last boat I had all the accessories, alternator, stereo, etc hooked up to my switch, and changed it from battery 1 or 2 depending on how long I was running the stereo, then when the boat was running I had it switched to ALL position. I'm reading people running one battery for starting, and 2 bank batteries for stereo, but I don't know how to set that up.

Thanks for the help!

There are lots of recent threads with battery options. I am just running 2 115ah batteries I picked up at costco last year for $85 each for my stereo bank.

It's really easy to wire up 2 stereo batteries. You just get 2 of the same battery and wire them in parallel(+ to + and - to -), then hook the positive terminal of one of those up to your switch. You will also want to connect the negative of one of those batteries to the negative of your starting battery, which will be connected to the ground wire from the enging on the boat.

I didn't wire my stereo to the switch. I just wired my amps directly to the stereo battery bank. That way I don't have to mess with the switch at all. I just leave it on 1 to start the boat using the starting battery. If the starting battery dies, I can switch it to 2 to use the stereo batteries to start the boat. You will probably also need an upgraded alternator or onboard charger.

Did you get AGM battery or Wet Cell?

I have an onboard 3 bank charger I just purchased.

I run wet cell batteries

Originally Posted by jrw160

There are lots of recent threads with battery options. I am just running 2 115ah batteries I picked up at costco last year for $85 each for my stereo bank.

It's really easy to wire up 2 stereo batteries. You just get 2 of the same battery and wire them in parallel(+ to + and - to -), then hook the positive terminal of one of those up to your switch. You will also want to connect the negative of one of those batteries to the negative of your starting battery, which will be connected to the ground wire from the enging on the boat.

I didn't wire my stereo to the switch. I just wired my amps directly to the stereo battery bank. That way I don't have to mess with the switch at all. I just leave it on 1 to start the boat using the starting battery. If the starting battery dies, I can switch it to 2 to use the stereo batteries to start the boat. You will probably also need an upgraded alternator or onboard charger.

How many watts are you running from your amps? I was thinking about getting costco batteries I just didn't know how they held up compared to deka's.

I am running about 2200 watts. I bought the costco batteries at the beginning of last season and they held up fine. I figure for the price of the deka's, I can replace the costco batteries 2 or 3 times and still come out ahead.

If your starting battery bank and your stereo battery bank are using 2 different types, sizes or amoutns of batteries I would run all your stereo(everything related to the stereo) straight to the battery bank and all of the other stuff(vital stuff) directly to the starting battery or common terminal on the switch. Run your main positive from the starter to the common terminal on the switch, the battery 1 terminal would be wired to the positive of the start battery and the battery 2 terminal would be wired to the stereo battery bank. The main negative starter cable that connects to the block will go straight to the negative of the starting battery. Then run a cable/jumper from the negative of the starting battery to the negative of the stereo bank. When sitting and listening to music turn switch to position 1. This will seperate the stereo bank from everything else. This will leave you with a fully charged starting battery ready to fire the boat up. After starting and running for a couple minutes then turn switch to both. This will charge and equalize both battery banks together. If you have a huge stereo bank and discharge it pretty far you may want to only leave in the both position for 5 or 10 minutes and then switch back to position one for 10 or 15 minutes. If you jsut leave it in both your alternator may end up workign way too hard for an extended perios of time causing premature failure. You can get some sort of smart solenoid like a blue seas, sure power or cole hersee and it will do all of this automatically. I would also highly suggest an onboard charger to plug in at night. If you do this just make sure you wire it right so you can completely sererate the banks for use with the onboard charger.

Originally Posted by jrw160

I am running about 2200 watts. I bought the costco batteries at the beginning of last season and they held up fine. I figure for the price of the deka's, I can replace the costco batteries 2 or 3 times and still come out ahead.

How much play time can you get about of your set up before you need to give them a charge? Can you go a whole day with a couple hours boating and the rest sitting play music?

Remember Costco doesn't make batteries. Deka was making come of theirs for a while but didn't want to dick around with their long free replacement warranty length. If the Deka is a flooded dual purpose battery compare it to the same group size dual purpose Deka. If a Costco marine/rv starting/deep cycle group 27 compare to a Deka DP27 or if it is a dual purpose 24 compare to Deka DP24. Compare apples to apples. The dual purpose deka's should be much if any more then the coscto dual purpose batteries. The Deka's are manufactured in the USA. The costco one's may or may not but are either going to be Exide's(have a pretty poor history) or Johnson controls.

As a side note we are most likely going to see a change in how batteries are warrantied. In the past batteries were classified and warrantied on their expected life, like 4 or 5 or 6 year batteries. There is generally a free replacement period(a year or 2) and then the remaining warranty is prorated. The problem is the proration rate is based off of a sometimes made up List price. Most batteries aren't sold for list so even though there is warranty life in the battery you may not get anything back because you have already used up your prorated value of what it would cost to replace the battery. Recently Napa(I think) went to or lost a lawsuit about how this is calculated. I wouldn't be surprised if all manufacturer's went to just a set free replacement period on the batteries and no prorated warranty period. I for one am completely fine with this as the prorated warranty is a pain in the arse. In addition way to many people think warranty includes anytime the battery stops working instead of what it actually means(for the most part) that the warranty covers failure caused by manufacturer defects. 99% of the time someone that brings in a dead battery has nothing to do with a manufacturer defect but because of misuse, been cycled too many times, something wrong with their starting/charging system.

Sorry, you guys probably didn't need that last part.

I can usually go all day without much problem. I think they died once last year, but we were playing at high volume for 6-8 hours nonstop.

The ones I have are marine/RV starting/deep cycle group 27 and were $75 each plus $10 core charge. 1 year free replacement then prorated after that. 115ah each

Originally Posted by jrw160

I can usually go all day without much problem. I think they died once last year, but we were playing at high volume for 6-8 hours nonstop.

The ones I have are marine/RV starting/deep cycle group 27 and were $75 each plus $10 core charge. 1 year free replacement then prorated after that. 115ah each

That is a pretty good price for a dual purpose 27. I can sell our DP27 for around $100 not including a core and can drop the price 5 or 10 with a core. Not sure that those can have a 20AH of 115. That sounds like reserve capacity at 25A. I will have to check them out next time I am at Costco. Costco tends to bounce through battery vendors because it is really a bad deal for battery manufacturer's because Costco takes anything that resembles a warranty back and probably expects the manufacturer to reimburse them for them.

I did just look online and I think they may be Johnson controls batteries which I believe make Interstate batteries. I wonder if they are the same as an Interstate SRM-27. If so that is a pretty good battery to I believe. If you have the height go to an SRM-29 or DC31DT in Deka.

Originally Posted by polarbill

That is a pretty good price for a dual purpose 27. I can sell our DP27 for around $100 not including a core and can drop the price 5 or 10 with a core. Not sure that those can have a 20AH of 115. That sounds like reserve capacity at 25A. I will have to check them out next time I am at Costco. Costco tends to bounce through battery vendors because it is really a bad deal for battery manufacturer's because Costco takes anything that resembles a warranty back and probably expects the manufacturer to reimburse them for them.

I did just look online and I think they may be Johnson controls batteries which I believe make Interstate batteries. I wonder if they are the same as an Interstate SRM-27. If so that is a pretty good battery to I believe. If you have the height go to an SRM-29 or DC31DT in Deka.

I'm pretty sure they are the same battery. I was at costco a couple weeks ago and wrote down the specs. Everything matches in dimensions, CCA and MCA.