so full range speakers are like factory speaker. they're only one driver and play many frequency ranges, right?
Eh.....your factory speakers are more like co-axials than anything because they have a "whizzer" cone for the higher frequencies (which, basically replaces the tweeter).
You won't find many (if any)
true full range speakers in car audio. It's more of a home audio thing (which is what both of those speakers I linked to earlier were).
But, like I said.....many car audio companies use the term "full range drivers" to just describe their co-axial speakers.
Co-axial speakers are like my Alpine SPS-170A and Alpine SPS-690A and also Pioneer TS-A1681R speakers, right?
Yup.
and for midrange speakers i don't understand. whats a good example of a midrange speaker at Crutchield?
Crutchfield doesn't really have anything. But, look here at the Boston Pro6.53 3-way component set:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=1076 See how it has two pair of drivers; a larger set (on top) and smaller set? That smaller set of drivers would be the midrange speakers. The larger set would be the midbass drivers.
Same thing here with the Focal's:
http://www.woofersetc.com/index.cfm?fuseaction=product.display&Product_ID=1169 - The middle driver there is the midbass, and the smaller driver on the right is the midrange.
aren't comps made up of midrange speakers and tweeters or are they made up of woofers and tweeters?
Depends. In a 2-way component setup, there is just a midwoofer (sometimes just called a "mid" because it covers both the midrange and midbass frequencies) and tweeter. In a 3-way setup, such as those I linked up above, there is a dedicated midbass driver and a dedicated midrange driver, aswell as a tweeter.
would i have to add all these different type drivers to have a really great system?
Well, to have a really great system you need to cover the entire frequency range with drivers capable of clean, accurate performance.
It doesn't really matter the combination, as long as the entire frequency range is covered with drivers capable of accurately producing the frequencies you have dedicated them to play. Some people use a 3-way frontstage (midbass, midrange, tweeter), some people use a 2-way front stage (midwoofer [that plays both midbass and midrange frequencies] and tweeter).....there's a ton of different ways to accomplish it.