What are the advantages or disadvantages(if any) of an active loudspeaker versus a passive loudspeaker? Also what are some well designed active loudspeakers?
What you read in previous messages is all quite true, but there are a few "buts" - as ever.
Manufacturers do not shy away from el cheapo hybrid amps, and these are not shunned for no reason at all. In translation, this means you will have to dish out substantial amounts of money to get the real thing.
The best active speakers I have heard over the last few years are still made by England's ATC. Dynaudio also makes some, but you could find that for some obscure reason, they are not sold in the US (these things do happen, such as with my H/K 680 integrated, my Yamaha CDX-993, etc).
The payback can be stunning. Literally. It can have you standing or sitting in awe. You could hear dynamics such as you have never heard before, including well known electrostatic speakers. You could hear details you never knew were there, even if they come from your own favorite CD or LP. You could experience a life in music you never knew was there. And the passion - ah, the passion is what will finally marry you to the concept forever.
As it did me.
Cheers,
DVV