Does adding a sub and amp effect milage? is it safe to do?

This is my first post. Just traded in my gas guzzling Lexus GS300 for a nice shiny new red Prius. Best thing I ever did. The only complaint I have is that the stereo is a little weak, nothing that a nice subwoofer can't fix.

I have a JL single channel 250 and a JL sub (10 inch with enclosure that would fit nicely in the trunk)

lots of questions
1- Is this going to kill my gas mileage?
2- Am I going to screw with what seems to be a very tight control of how the car uses its electricity?
3- The 12v battery seems to be non-standard, again, am I asking for trouble.


I was hoping to cross over from the rear speakers and adjust the bass volume by fading front to back. With the battery in the back this should be a pretty easy installation I would think. (I am a beginner still). The amp on and off could be hooked into the cigarette lighter. Am I on the right track.

thanks in advance
Steve

 

<div class='quotetop'>QUOTE(Bill Merchant @ May 29 2007, 01:32 AM) [snapback]451335[/snapback]</div>

Thanks Bill. I actually searched the entire site and never found a definitive answer about how much, if any, loss in gas mileage you can expect from adding a sub. I can't imagine that it is drastic since the power needed to move a speaker cone has to be far less than the kinetic energy required to turn a wheel. Do you know anyone who did an A/B test on this?


All in all, this in a wonderfully designed car. Heck, I even found another secret compartment to put my junk in. The little sliding tray under the cup holder in the front arm rest.

thanks