Is there an upgraded alternator for the 3g rdx?

 

you mean aftermarket with more power? Explain why

 

Yes aftermarket with more power and its For car audio i would like to run a 250 amp altenator

 

You don't need that much power for car audio.

 

You might if you intend your car audio system to register on the seismic scale.

 

I stand corrected.

I do live sound for a living, and can easily run four "2000 watt" 18" subs on a single 120V 15A circuit (1800 watts total) without tripping breakers.

Wattage ratings on amps are BS literally 100% of the time. They quote peak draw not RMS, but the latter is what matters.

 

Im running a taramps smart 3 bass with a american bass 12 the vfl comp 12 and in some songs with heavy bass i go into protection mode so maybe i need a bigger amp? Or secondary battery?

 

You need a much bigger amp for that sub. When you drive an amp into clip it distorts which causes many problems. You can even melt the voice coil on the woofer itself.

That sub looks like it wants 2000 watts RMS / 4000 w peak, but your amp only does 1500 w RMS / 3000 w peak. Get a beefier amp and turn down the input trim, and see what happens. Also worth hi-passing the sub at 25 hz or so - trust me you can't actually hear frequencies below that.

Edit: I just looked up that second sub you mentioned and that amp is also severely underpowered for it. And if you have BOTH wired in parallel and you're presenting tiny (<1 ohm) load to the amp... there's your problem.