Change to Horns or stay Dynamic

I dont feel active has any advantage in sound quality over well designed passive, you will get greater dynamics for you are running multiple amplifers with an active and a bit less insertion loss over passive but this is a nonissue if networks of proper design.

I agree that "well designed" is far and above more important than active or passive...good drivers and good drivers selection and implementation is fundamental starting point for a good speaker no matter how it is amplified...which is why I trust design to experts like yourself!

although....

How about eliminating IMD and higher order harmonic crossover distortion from an amplifier for a large bass woofer driving both a woofer and a tweeter?

Correcting for Phase?

How about using a Class AB for the woofer and pure class A for the tweeter?

Fundamentally there seems something at cross purposes in most passive designs where you hook up the same power source to something as delicate and sensitive as a tweeter (milli amps) AND to something as big and powerful and thunderous as a bass woofer (amps)...

Active Speaker Proponent

Pacific,

Your argument about home audio listening is valid if you listen at fairly low average spl levels of lets say, around 75db. Because for a good sense of dynamics a loudspeaker must be able to easily handle 20db peaks above the average level with no compression. Thats the minimum requirement and unfortunately the Scan favorites fall short of this target at anything above mid 90's db. So if you want to listen at realistic average levels of say 95 -100 db you will need the speaker to handle a not-so-unrealistic 120db peak levels and that's at the listening position no less.

For audiophile drivers core size and voice coil size are of secondary importance. Contrast this with the pro drivers' big voice coils and oversized and vented magnetic cores that can sustain prolonged periods of abusive power (read 400-600 watts) with just maybe 2db of thermal compression while playing at around 120db average level. There really is no comparison! Thermal compression is real and one of the most important as well as overlooked parameters in loudspeaker performance. It's perhaps not surprising that this is the case for the audiophile speakers as the driver core is the most expensive part of the assembly and the designers using the same logic consciously chose this set of compromises.

But make no mistake, as excessive as these db levels might seem at first, for the person that wants realistic reproduction at the home this is what will be required of the system.

Cheers,
George

Dgad: You bring up a common misunderstanding about active systems. Many do have built-in amps, but that's not necessarily a given. Some use external amps, e.g., Linkwitz Lab Orion, Gradient Revolution (I think), Morrison, Nomad Ronin, among others, including what I build.

Yes, the initial set-up is a little more involved, but once you've got it connected, you're done. The gains of active out weight the extra work. And if you want control, an external active x/o allows for far greater control than a fixed internal passive.

Here's another link that goes into the specific benefits of active: http://www.tnt-audio.com/casse/active_speakers_intro1_e.html

Thermal compression is real and one of the most important as well as overlooked parameters in loudspeaker performance.

Absolutely...northern european woofers with a voice coil the size of a mere tweeter and a metal phase plug to try and keep cool the pole and connected to a lightweight rigid driver work well up to mid 90's at 1 meter.

Great engineering for great sound at modest levels for low cost but far from realistic reproduction.

On the other hand - money saved from purchase of expensive drivers can go into woodwork and veneer to create a work of art...

Great point George!

For audiophile drivers cone size and voice coil size are of secondary importance. Contrast this with the pro drivers' big voice coils and oversized and vented magnetic cores that can sustain prolonged periods of abusive power (read 400-600 watts) with just maybe 2db of thermal compression while playing at around 120db average level. There really is no comparison!

Agreed - "there really is no comparison".

I'd re-iterate to try Shefield Labs Drum Tracks on a pro design speaker like (PMC, ATC, Meyer, Westlake, custom Augsperger and many other pro designs) and your audiophile ears are in certainly in for a big surprise...hey that actually sounds like a real drum set in the room!

(Bear in mind mastering engineers compress the crap out of what you mostly can buy in recorded music - so you won't always achieve realism except on recordings where dynamics have been deliberately preserved.)