hi guys. well i got a CDT 3-way set of speakers that i will hook up to a 2-channel amp. now im new the componant scene. but i assume this a passive set up, correct?
Yes.
i read a lot of guys going active, which i think is directly hooking up speakers to an amp without a xover, but not sure on that.
An active crossover is required to "go active". The active crossover filters the signal
prior to amplification. So, yes, the speakers are then hooked up directly to the amplifier, and each amplifier channel's input is fed an already filtered signal by the active crossover. Also, to "go active", you need one amplifier channel per speaker. So, you'd need 6 channels of amplification and a 3-way active crossover.
what are the advantages/disadvantages for passive??
Advantages; crossover points/slopes are optimized for the speakers. Additional
doo-dads (yes, that's the technical term) can be easily incorporated into them such as zobel networks, tweeter protection, etc etc. Also, less amplifier channels (and hence less space and money) are needed.
Disadvantages: Crossover points and slopes are static and (usually) can not be changed to fit certain situations better. Passive crossovers can be "power hungry" and waste some of the input power you are inputting to them. For the people who like to switch drivers frequently (the DIY'ers out there), using a passive crossover makes it very difficult and inconvient to try to switch drivers and still use the same passive crossover.
If you have to ask these types of questions, IMHO you should not go active. Chances are, you'd do more damage than good trying to go active. Keep the passive, get acquainted with component sets and how to properly set them up and tune them, etc etc. Just learn the in's and out's
really really good first. Without a good working knowledge of the terms, definitions and concepts of speakers and component sets, chances are you'd have worse results with active than if you took your time and properly setup and installed the comps using the passive.