Seems like you are figuring it out, but man does this thread bring back memories of highschool. My friends and I were car stereo's 24/7.
What was really funny is how all those terms came back in my Circuits classes at college and how easy it was to pass once I linked the two...speakers (resistors), amps (amps/op amps), caps (capacitors), etc.
And my parents said all that stereo crap was a waste of time and money..sure showed them!
