Active speaker, the future? or another fad?

Exert - the trick in bi(multi) amping is to know what the designer has done in the passive x-over. Not easy, I know. I wonder if Mr Thiel would give suggestions re, going active in the bass (if s/one were serious about this of course).

The point is, a line-level x-over is fed low level signals, and is much more stable in its filtering action (and often, cheaper). Also, an amp connected to the voice-coil (or nearly) is a much more efficient way of using amp power.

One of the problems with passive x-overs is they perform differently given the power fed to them (which is high), influencing the amps, the frequencies, creating magnetic fields, etc, etc, ad nauseam. If you get it right with a 1kHz sine wave at 1W, it won't necessarily sound "right" with music (multiple waves) at say 8W, etc.

Hence acoustic tests to fine-tune a spkr through the x-over

The bass is a very good first target for discrete amplification. There, all that's needed is usually the x-over frequency & slope; you'd also check for baffles step compensation and any other trick in the x-over (there won't be many). These points are easily addressed with an active filter (yr typical Behringer allows a choice of different slopes, frequncies of course, time delay, transform functions, frequency boost or attenuation etc). If the spkr manufacturer helps with info, it should be possible to get good results (probably better than the original passive) with more, but less expensive amps, by keeping the mid-high x-over as is passive, (one amp, low-medium wattage) and pulling out and biamping the bass region (higher wattage).

People like Nuddel (Genesis sp?) have been offering this, at a price!

Gregm, why whould you go through the trouble of dissasembling a speaker, bypassing the crossover for the bass woofers, AND NOT MAKE THE UPPER MID/TWEET DRIVER(S) ACTIVE AS WELL!!!? This doesn't make sense. Yes, I can see the advantage of actively driving the bass w/electronic outboard crossover/amp combo. But, if you're going to do that, why not make the whole freakin speaker active, and use one outboard electronic crossover?! This makes more sense. Unless however, like I mentioned earlier you start running into problems in frequency response and such from the mid/tweeter by "ditching the stock passive". In that case, I understand leaving things "as is".

NHT is giving it a shot. They have a $5,000 full active system includes speakers, amps, crossover, and some exotic software with like 1,000 bands of eq. Speakers are monitors with the SEAS magnesium drivers and a separate sub. There was a thread at A-A a few weeks ago.
This systems is supposed to eliminate the ringing of metal drivers and other problems a passive system can't fix.

why (...) NOT MAKE THE UPPER MID/TWEET DRIVER(S) ACTIVE AS WELL!!!?

Good point. As you imply, it's a compromise of sorts.
The reason is that most of the energy goes in the bass region, so the biggest immediate improvement would be an amp dedicated to that region. As less energy hits the mid-highs, distortion is somewhat less AND more importantly, a good amp can control the system without being a mammoth and devoting +50% of its power to the bass alone (i.e. so much lost for the mid-high region).
I.e., as you go up the spectrum there's less musical info, so your average tweet rarely gets hit with more than 5W, and that's playing the system LOUD.

I forgot to mention the new Meridian speakers or the new Pass Labs speakers. I think the Meridian and Pass Labs is are a shot at a true SOTA active speaker. I don't know how either of them have been excepted, but Pass Labs certainly knows how to build amps, with a little help for the speakers... who knows?

If every connection is a loss of signal, and subtractive crossovers compound this loss, it seems like this could be a very benificial setup. If I could find the right product, I would sell my amp, speakers, and speaker cables! Active speakers seem, on paper to have so many benefits and few drawbacks other than the obvious lack of ability to swap amp, speakers, or speaker cables.

Has anyone tried some of the better active speakers?