Quick question on ohm and watts

[blackink 10+ year member]

If I'm getting a subwoofer that is 1.4 ohms dvc and when I wire it for .7 ohms, what's the formula for calculating the wattage produced by and amplifier that is stable at 1 ohm? Like how much would a saz 1500 produce at .7 ohms?

Also would a stock alt but with big 3 and a batt be enough to power this or should I add another one?

Lastly does the gain setting limit the total wattage produced? Like is setting the gain 50% equal to limiting a 3000 watt amp to only 1500 watts? I'm asking because I want to know how I could limit the total output if I don't feel my car's electricals can currently handle the full power.

Thanks

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[blackink 10+ year member]

anybody?

 

[IamDeMan 5,000+ posts]

7!

 

[blackink 10+ year member]

bump

 

[bubbagumper6 5,000+ posts]

If I'm getting a subwoofer that is 1.4 ohms dvc and when I wire it for .7 ohms, what's the formula for calculating the wattage produced by and amplifier that is stable at 1 ohm? Like how much would a saz 1500 produce at .7 ohms?

There is no straight formula, but it's usually linear. ex. 1000w @ 2 ohm, 2000w @ 1 ohm, would then be something like 2250 @ 0.75 ohm. This is just an estimate, unless the manufacturer specifically states what the amplifier will do at that impedance, you can not know for sure (without bench testing).

Also would a stock alt but with big 3 and a batt be enough to power this or should I add another one?

Assuming that amp is 1500w, a stock alt with 1 batt is kind of wimpy, you'll have voltage dips, a second battery would be better.

Lastly does the gain setting limit the total wattage produced? Like is setting the gain 50% equal to limiting a 3000 watt amp to only 1500 watts? I'm asking because I want to know how I could limit the total output if I don't feel my car's electricals can currently handle the full power.

The gain does limit the output but not in the way you think. 100% gain does not mean 100% power. You can use it to limit the amp like you want, but you need to do some more research on how the gain works. I recommend this site: Basic Car Audio Electronics