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by **William from NOLA** » Tue Mar 14, 2006 5:19 pm

With a second battery, it will definately keep your voltage from dropping low when current is in demand. BUT, given the additional 10 amp load, you alternator will be hurting more than before.

Not quite the same effect as adding a cap, but it is similar.

by **audiobass10** » Tue Mar 14, 2006 4:11 pm

GlassWolf wrote:a shot of penecillin can be useful if ya get the clap too, but isn't it better to avoid getting the clap instead?
:)

Yup.

Really, it's gunnna depend on how loud he plays his system anyways. If I run my Viper D1200.1 ran down to 1ohm (rated for 1200x1@1ohm) on volume 30..I have absolutely NO problems with voltage drop even at idle..now when I turn it up to volume 45..I obviously start getting a slight drop. Thats with a stock 90A alt. So, if you tend to play your volume at moderate levels..the alt may never be an issue, but many love to crank the volume knob :happy055:

by **GlassWolf** » Tue Mar 14, 2006 4:05 pm

a shot of penecillin can be useful if ya get the clap too, but isn't it better to avoid getting the clap instead?
:)

by **audiobass10** » Tue Mar 14, 2006 4:00 pm

GlassWolf wrote:there's a thread in the guides area on speaker power handling. worth reading.
as for the batteries, the battery should be in a charging state when the car is running. If the car's voltage alternator is being overdrawn to the point that you have to rely on the battery for more than the occasional momentary drop to 12 volts, you have problems, and a second battery may extend runtime a bit but you're still clipping the amplifiers, and still damaging the alternator.
fact is the alternator should supply all the needed current for the car when the engine is running. that's why the alternator voltage is higher than the battery voltage. to charge the batteries.
a car battery has one purpose. to supply power enough to turn over the engine and start it.
after that the battery should at most, act as a DC voltage filter.

I was just trying to make it a point that they can be useful while the car is running (whether or not it's the best way of doing things) as far as voltage dips go.

by **GlassWolf** » Tue Mar 14, 2006 3:53 pm

there's a thread in the guides area on speaker power handling. worth reading.

as for the batteries, the battery should be in a charging state when the car is running. If the car's voltage alternator is being overdrawn to the point that you have to rely on the battery for more than the occasional momentary drop to 12 volts, you have problems, and a second battery may extend runtime a bit but you're still clipping the amplifiers, and still damaging the alternator.

fact is the alternator should supply all the needed current for the car when the engine is running. that's why the alternator voltage is higher than the battery voltage. to charge the batteries.
a car battery has one purpose. to supply power enough to turn over the engine and start it.
after that the battery should at most, act as a DC voltage filter.

by **Chris from Washington** » Tue Mar 14, 2006 3:51 pm

When your car is running it should be getting all it's power from the alt. not the battery. The battery is mainly used to just start the car, and for engine off power.
Running another battery is also going to put additional strain on the alt because now it has to try and keep 2 batteries charged, instead of one, plus run all the electronics in the car when it's running.

by **audiobass10** » Tue Mar 14, 2006 3:30 pm

GlassWolf wrote:the secoond battery isn't going to help when the car is runing.you'd need a larger alternator.see the FAQ section on charging systems.

Why wouldn't the Extra batt help while the car is running? Are you saying it wouldn't help keep voltage up. The two batts would act just as one BIG battery anyways..running a second batt has helped in my experience, but you tell me the facts :) .

by **Ryan from Ohio** » Tue Mar 14, 2006 3:09 pm

Heres my favorite saying:

A 100 watt speaker can be as loud as a 4000 watt speaker given thigns are the same

Power requirements by no means makes a sub loud, period. Anyone who tells you otherwise doesnt really know WHAT they are talking about.

Bottom line. You can buy all that cheaper stuff and end up investing more into it that you would be to take our advice, buy better quality lower powered stuff. Not only will it sound better, be louder and last longer- it will probably be cheaper or the same money.

by **GlassWolf** » Tue Mar 14, 2006 1:46 pm

if you're set on those dual subs, say the word, but here's my suggestion.

you're on a limited budget I assume, so instead of two dirt cheap subs (which will perform as such) consider one, better sub. you'll be just as loud or louder, and with better sound quality.

If you stick with those subs, they'll need about 1Kw between them, at a 2 ohm load combined, so you'll be looking for a class D mono amp that puts out 800-1200 watts x 1 @ 2 ohms. Expect to pay $200-350 for such an amp, and that amp will draw about 120A of current at peak output. continuous draw will probably be around 50-60A.
If you go with one better sub (say a 12" AA, EA, or RE sub) you'd be looking at about $100-250 for the sub, and $50 for a box built for the sub.. and you could drive that with an amp rated for 300 watts RMS and get great results with less power usage.

the secoond battery isn't going to help when the car is runing.
you'd need a larger alternator.
see the FAQ section on charging systems.

by **JeremyC** » Tue Mar 14, 2006 11:07 am

05spectraSX wrote:Hey i'm getting a 2 12'' subwoofers kicking out 1,100 watts.

Subs don't put out watts, amps do.

05spectraSX wrote:I'm going to get a 800watt wiring kit for everything. But what size amp should i have to power the subs. I want one that will power the best 1,100 watts but i don't want the ampage to be so much.

1100 watts is a peak rating not RMS. As a rule of thumb, never pay attention to a peak rating. Look at the RMS rating, and match your subs and amps accordingly.

05spectraSX wrote:Can i use a 800 watt amp to power them or anything less? The subs continuous power of 600 watts.

I wouldn't go over 600 watts if thats the rms rating. Especially if your talking about a low end brand like dual.

As they all have pointed out, you can do way better for the money. Check out the good, bad,and ugly in the FAQ section and it will lead you in the right direction.

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