Crossover ? Passive Vs. Active

I'm with Undertow and Tim196. Active is definitely better from a technical perspective but less flexible than passive for tailoring the sound to individual taste (particularly if you like added harmonics from tube power amps to warm or sweeten the sound).

With an active xover, one can pick and choose xover points, levels, and even the Q on some models. I think the amp choice is less of an issue when you have such flexibility in the xover. Bob's comment is right on.

Losing an inductor [in a conventional woofer xover] with yards and yards of nondescipt wire is a huge advantage in an active system. But 4, 6 or more amps just isn't in the cards for most of us. Perhaps active monitors are a way to go, but I always wondered about the quality of those amps, and how they are subjected to the vibrations of the spkr cabinet. And most are geared to the pro market, for "accuracy" and not necessarily hi-fi.

I'm running my two-way Apogee Duetta Signatures with a Marchand XM9 active crossover. One thing you always have to be concerned with when going to an active crossover is that you can smoke a tweeter or midrange driver fast. Remember, once you go active, you have by-passed any and all filter capacitors connecting to the tweeter and(or) midrange drivers - any frequency can pass to these drivers now. For this reason, it is imperative that your amps powering your mid-ranges and(or) tweeters must not pass any DC, and must not have any power-on "tumps" as well. You would be surprised how may good amps pass a little too much DC to be used for bi-amping.

Anyway with that being said, since I have gone active, I'll never go back to passive - at least with this set of speakers.

the amplifiers will be much smaller in power rating and will be economical.

Not really. If you have say a 100 watt amp for a three way speaker, you are still going to need an amp very close to that level for the woofer, and you will need 2 more amps to boot. Yes, the midrange and especially the tweeter will not need as much power but the quality still has to be there. Even if you could get by with 3 amps that had 1/3 the power it would still cost more than a single higher powered amp. Going up the power chain of a power amp line doesn't double the cost when you double the power . It is a fraction of that.

I agree that a well executed system with an active crossover has many advantages for the reasons listed, but saving money is not one of them. Quality amps of any power level are not "economical."