Number 2

iTrader: (1)

If I can make room behind a panel here I'm gonna put my yellow top in the trunk and use an isolater with a red top up front. That would be pretty cool. I really beleive in optima batteries for winter use.

JohnVroom

A second battery in the trunk may cause real alternator noise issues. A second battery is seldom needed.
Your friends comment on the yellow top looking like it needs to be charged all the time is electrical balderdash.
The red top is a starting battery with 50 deep cycles guaranteed (that’s a lot) the yellow top is not a starting battery (though MANY use it to start their car) but it can do LOTS of deep cycles. If you run your stereo a lot with the engine off then the Optima is a good choice over less expensive wet cell batteries, two batteries as chevysq and lemonlime were saying is overkill UNLESS you have a VERY demanding system or listen for hours on end in your car.

Chadxton

iTrader: (1)

Doesn't sound really like an o/k system if you consider you won't be doing much engine off listening. I don't plan on beefing up anything other than the alternator on my car, and just a single conventional moderately high output batt for the (to-be) 5 amp system. Really, the main power monger in your system is going to be the amp(s) for sub bass section. A 1000/1 pulls...what? 30 amps continuous at a moderate listening level? I wouldn't be worried.

JohnVroom

Paulnold, your friend has expensive ideas for your wallet... does he sell this stuff? Or does he want you to follow his lead?

Orion_95

running a red top AND a yellow top is not only useless, but a bad idea. Pick one.

Mini Steve

Personaly 1 batt is more than enough. Had an yellow top for 2 years or so now. I do listen to the system more with the car of. Again drive it too. Top it up every so often. you should be fine! 2 is cool but a real pain end too expensive.

geolemon

Actually, your friend is, if anything, backwards in his thinking..
And, some of this ties to the old "capacitor debate" believe it or not...

Something that's not considered often enough is the transient response of the battery (which is what gets to the very core of what role capacitors play in your system ).
The transient response is how quickly the battery can provide current to the electrical system, when a demand is present.
One which is slow, has a relatively slow ramp-up time in discharging current.

Put concisely, the same properties of a deep-cycle battery that make it able to survive discharges without damage (the thicker plates) also contribute to it's inherently slow transient response.

The standard battery is the better performer, one that is able to respond quickly when called upon, able to actually give the current it's being asked to give. The trade off is that it will be damaged if abused, if deep-discharged...
A deep-cycle battery is built like an armored car... able to take lots of abuse, but you wouldn't take one to a drag race or autocross course. [img]graemlins/thumb.gif[/img]

Capacitors tie into this, because any time your alternator's current capability is exceeded for even a moment, it's voltage level drops (quickly) down to that of the battery... at which point the battery provides whatever current the alternator could not, both working together as a team.
And you'll notice your headlights dimming, because headlights are brighter on 14.4v (the 'alternator working solo' voltage level) than they are at 12v (the battery's voltage level).

Although it's only milliseconds, it does take time for your alternator's voltage to drop, and then once it reaches 12v, additional time for the battery to respond... longer, for a deep cycle battery.

Let's assume that was because your battery needed more current to make the power the music was telling it was required for some dynamic burst in the music...
Did your amplifier get the current it needed?
Or by the time the battery was able to meet the current demands, had the transient passed?

Why do I mention capacitors?
Capacitors, you'll note, charge up to the maximum voltage of the system... essentially, they'll be charged up to 14.4v.
So, the moment the alternator's voltage begins falling, they will begin discharging, fulfilling the demand of that millisecond, covering that oh-so-brief moment in time that it takes the voltage level to drop, and the battery to respond...
By the time the battery is able to supply the full amount of current, the capacitor is nearly depleted... it doesn't last long...
Hopefully, your battery responds quick enough that this little on-ramp-assistant was able to smooth the road.

I'm not an advocate of deep-cycle batteries, for audio system performance reasons. They are like 80,000 mile treadwear tires. Yeah, they last a long time.. but god, don't they just suck to drive on? Complete performance sacrifice.

I'm also not an advocate of listening to your system with the car not running...
There's absolutely nothing good to be gained from this, only the potential for getting stranded and damaging your batteries.

Hope that helps... [img]graemlins/beer.gif[/img]

lemonlime

I agree, This Optima has been a fantastic battery so far, even on the coldest of days.