07 Camry w/ 1040-watt RMS 4-ohm amp, should I add a 2nd battery & isolator?

[ToyotaLexus]

I have finally finished adding 3 amps and 2 sub, as well as a DVD navigation system, to my '07 Camry.

Two amps are each rated 270-watt RMS @ 4 ohms. The mono sub amp is rated at 500-watt RMS @ 4 ohms.
(but I have it hooked up to two subs @ 2 ohm, so the wattage may be higher) ...so that's about 1040 watts
continuous RMS @ 4 ohms in total. The maximum rated wattage is even higher, but I don't think those
figures are accurate.

The DVD nav is the Eclipse model that power folds down.

I was foolish enough to watch a DVD with the volume turn up high, while the engine was off.
Took less than 30 minutes before the digital voltmemeter that I added started to beep,
indicating that my battery was approaching the 12.0 low battery limit. I shut everything off
and started the engine.

Can my 07 Camry's stock alternator handle a secondary battery, such as Optima Yellow Top?
I want to add a battery isolator so that the stereo system will only drain the Optima
battery when I listen with the engine off....

Any advice appreciated!

[wireless]

If you want an isolated DC electrical system for your stereo, then that would be the way to go. You may also want to look into a 1 farad capacitor to smooth out the peaks and valleys of your systems power demands.

BTW: If you are running your (2) 4-ohm subwoofers in a parallel circuit on the mono channel amplifier, the load to the amp is 2-ohms and your power output should be approximately double (so each sub is getting the 4-ohm rated RMS power). That said, the distortion at 2 ohms is going to be a bit higher than at 4 ohms and the current draw of the amp is going to be higher (i.e. make sure your fuse protection and wire sizes are appropriately designed).

Po = Pr x (Zr / Zt)
Power Output = Power Rating times (impedance at rated power divided by load impedancein parallel wiring)
1000w RMS = 500 w RMS x (4/2)

Either that mono amp is very expensive, or is a POS. What make/model is it?