Deep Cycle for stereo amplifiers?

[sudso]

Am going to be getting a deep cycle aux battery soon and wondering if they are ok to run car stereo amps.

Together, the amps are capable of drawing about 70-80 amps at full throttle but are mostly used up to half volume.

So I'm wondering how long the aux. batt will power them without being charged and what amperage my alternator will need to put out to keep up charge to both batts. with say 3x100W spotties, steroe amps, fridge etc going at once.
Dont want to connect the amps to the starter batt. as it has enough running off it already.

[drivesafe]

Hi sudso, if you are going to be using the sound system while your driving then you need to concentrate on your alternator’s output first as this will be the prime source of power.

If you are going to be using the system while the engine is off then I would guess that you will be replacing batteries on a regular basis.
AGM batteries may be able to handle this level of continuos current draw for longer periods than a standard deep cycle or cranking battery, but I would recommend you get some info from a sound system installer as this is a few whack of power to be handled by a battery.

If you had the room, I would suggest you install a number of batteries to share the load but you would still need to work out if it is easier to replace one battery every so often or to replace three or four batteries after a much longer period but at about the same ratio of time to that required for one battery.

Cheers

[Tiny]

then think about one of these

http://www.my4x4.com.au/onlinestore/sto ... duct=10274

[sudso]

then think about one of these

http://www.my4x4.com.au/onlinestore/sto ... duct=10274

Where are these available in SA Tiny?

[Tiny]

then think about one of these

http://www.my4x4.com.au/onlinestore/sto ... duct=10274

Where are these available in SA Tiny?

I send em out free freight

[icebreaker]

should be ok... i don't see why you would have to replace the batteries frequently.. you'll know soon enough whether the battery isn't keeping up.. I would personally run dual deep cycle, ie. Optima Yellow Tops.

The current your stereo draws is really going to depend on the volume you run it at.. If it is at a general playing volume than the current draw will not be great, if your cranking it then it might be reasonable.. but unless your playing it at a volume that is just uncomfortable then your not going to be coming close to the optimum current draw for the amplifiers.

I used to run a 6 channel (420W RMS, 65W x 4, 80W x 2) and a 2 channel (1600W RMS x 1) in my old car, using an optima yellow top, and never had a problem with it.. This included SPL Competitions as well as SQ competitions.

I'd suggest finding out how many 'amps' not watts your driving lights pull individually when one, your fridge, amps, etc and list them down.

The Amp(s) will have a rated amperage but remembering that that is dependent on the volume you have it at.. ie. 35amps.. this is basically the max rated current draw, hence it would have a 30-40amp fuse in this case. but you might only be drawing 10-20 amps at general playing levels.

Once you add everything up you can work that out against lets say an averal alternator of about 80Amps.. You might only have a 50/55Amp alternator..

Also remembering that your lights won't be on during the day, and whether you will have the stereo cranked when you have the head lights on, ie.. 4x4'ing, in which case you wouldn't add all the totals together because you will rarely be in those conditions.. Over kill with batteries will however give you a decent amount of life with devices on with the engine killed.


sorry for the lengthy reply.


Dan

[cloughy]

Current= Power/Voltage
8.33A = 100w /12v

[mitch86]

dude 80 amps will be fine with just any decnent battery aslong as you keep your engine running.

i was running 2000rms off my battery. (over 200 amps)

depends what size cable your using too. you might not even be using that much power from your amps because the cable is insufficent.

[sudso]

Hi sudso, if you are going to be using the sound system while your driving then you need to concentrate on your alternator’s output first as this will be the prime source of power.

I have to remove 2 or 3 things to see the damn specification plate on the alternator. Will do this on the weekend and while I'm there I'll test it under loads as well. It's a factory issue Denso.
[/quote]dude 80 amps will be fine with just any decnent battery aslong as you keep your engine running.

Scenario: We're down the beach fishing, the engine is off (I hope!), sinking a few brews, the stereo's cranked about 3/4's volume cos' the surf is really pounding and I am under the illusion that the fish are attracted to the loud music
At 3/4's volume the amps are drawing about 55 amps (about 70 amps at full power according to both amps. specs.)

So I'm wondering how suitable a deep cycle battery would be for supplying that amount of current for extended period's at a time.
I know they are designed for long slow outputs and can be flattened and recharged over and over.
I might need a minimum A/Hr but I dont know how much

depends what size cable your using too. you might not even be using that much power from your amps because the cable is insufficent.

Cable size is correct and distance from aux. battery to amps will be minimal.