steve_1979 said:
Although all things being equal, I do think that you can easily hear noticable and worthwhile improvements by using an active crossover rather than a passive crossover but the difference between them isn't quite as huge as some people would have you believe.*
well, that largely depends on price point and engineering skills of the designer. at price-no-objecttive price point you can make pretty good passive crossovers that will hardly be distinguishable from active, if at all. it's even possible that they would sound better since there's no active electronic (hence no extra THD) in passive components. and top-of-the-line passive components maintain very strict tolerances therefore exhibit marginal distortion contribution.
so you can build a passive xover using cheap ferrite cored inductors and 10% - 20% tolerance electrolytic caps and then have it compared to how the speaker sounds with an active one. the result is obvious. but then again you can get copper foil air core inductors (the best it gets ATM, nearly perfect theoretical inductor, great electrical and mechanical properties) and 1% - 2% tolerance polypropylene caps (AFAIK the best electrical performance ATM) and design a proper 1st order xover (for various reasons the best design yet). I'll be very surprised if you heard any audible difference then. note "audible". that's the main reason why there are still people who pee on active speakers, despite their arguable superiority.
the problem is that one coil will be easily more expensive than the whole active xover. but it's not the point here.
FYI; if you are so much pro-active you should know it's way more useful to do the whole xover business in digital domain rather than rely on cheap off-the-shelf active solutions.