no cap, right?

I have decided not to go with a cap, but i recently purchased a 12v lawnmower/quad battery at walmart. could i wire that battery by my amps just like a capacitor to help with my dimming.  I have the big three an upgraded alternator (200a), 1 run of 0awg to a distribution block then 4 gauge to 2 cheap sony amps.  My voltmeter drops as low as 10v on deep bass notes.  Ive re-positioned my amp grounds like 3 times, so im gonna try another battery by the amps. i need to get around to upgrading my big three from 4 to 0 gauge also but i gotta get the dough first.  Im just getting fed up with the dimming though, so another little battery couldnt hurt right???????Db electrical 200a alt

0awg wiring kit

Yellow top optima

2 pioneer premier TS30004DVC subs

Yep - Bingo! The battery should be much better than a cap. The exception may be if it has a high ESR - ie, internal resistance. But buggy etc batteries are usually Valve Regulated types (aka AGM, VRLA) which have a low ESR - typically under half that of other Lead-Acid batteries (whether sealed or open) including many gel-cels. Let us know if you still have problems. A bigger battery (hence lower ESR) may be better than another of the same.

do i wire it just like a cap? a wire from my starting batterys positive to the new batterys positive in the trunk then negative to chasis? and would a 100a fuse b ok for that?Db electrical 200a alt

0awg wiring kit

Yellow top optima

2 pioneer premier TS30004DVC subs

Wiring up that way is correct. I would use a fuse the same size as the one you're currently running for your ampsUNLABELED Custom Car Club President

i would run a cap before the subs ampboxead78

Use a relay between the batteries.Life is a series of temporary situations.

boxhead78 wrote: i would run a cap before the subs amp

Jep - but Jiz doesn't have a box for a head and has decided not to run a cap, but a battery instead (for reasons discussed elsewhere and previously). Jiz - I agree with running a relay, but it depends on how you want it rigged up. My preference is for a charger-controlled relay (ie, charge lamp else voltage sensing) that connects the batteries (ie - only whilst charging). That has the advantage of avoiding paralleled-battery issues (an issue with mis-matched or older batteries), and independence - ie, flatten the "audio" battery but you still have the primary battery available. I recommend a fuse at each battery's "outlet" if there is physical separation. EG - My ute has its enginebay battery thru a circuit breaker and the relay, to the tray mounted battery with its fuse. FYI - Independence was handy yesterday. Taking a swim off a remove 4WD track, I returned to a flattery - I left my headlights on. Merely reconnecting the aux-battery from the NO relay contact to the NC was enough to start the engine. The relay is a 60A SPDT and I run 50A circuit breakers. The starter is a reduction type that is normally 120A. I was expecting to remove the aux/tray battery for a normal jump-start, but my I took the opportunity for an experiment.