I'd only go for active PA speakers if there's something to be gained over the passive variant. Active speakers need more cables running, and the extra weight can make them fun to get on stands. I also like to keep amps somewhere I can keep an eye on them.
The most basic active speakers are the same as the passive version of the cabinet, but with an amplifier bolted to the back. They'll sound no different to the passive version with an external amplifier, but, if you're lucky, they will have included a high-pass filter to protect the bass driver. Not always the case, though.
Wharfedale EVP-X12P 300W Active PA Speaker at Gear4Music.com
The next ones up will have analogue active crossovers, and two amplifiers per cabinet.
This could be a worthwhile upgrade - the crossovers are often much higher order than the passive speaker would have, so the compression driver will be better protected against mechanical overload. There's a much better chance of a low-cut filter to protect the bass driver, and maybe some basic eq.
This is still easy enough to replicate with external amplifiers, though.
Behringer: TRUTH B2031A
The active speakers that are definitely worth having are those that have full DSP control over the drivers. They compensate for driver frequency response anomalies, provide RMS power limiting (lowering long-term power input if the drivers are getting warm), independent amplifier soft-clipping, active crossovers, full low-frequency driver protection (they limit above port tuning as well as below, to keep the driver in Xmax). They basically make it so that any signal you care to feed in will not kill or overload the amplifiers or drivers. Ever.
Behringer: EUROLIVE B112D
K12 Active Loudspeaker ? QSC
Chris
The most basic active speakers are the same as the passive version of the cabinet, but with an amplifier bolted to the back. They'll sound no different to the passive version with an external amplifier, but, if you're lucky, they will have included a high-pass filter to protect the bass driver. Not always the case, though.
Wharfedale EVP-X12P 300W Active PA Speaker at Gear4Music.com
The next ones up will have analogue active crossovers, and two amplifiers per cabinet.
This could be a worthwhile upgrade - the crossovers are often much higher order than the passive speaker would have, so the compression driver will be better protected against mechanical overload. There's a much better chance of a low-cut filter to protect the bass driver, and maybe some basic eq.
This is still easy enough to replicate with external amplifiers, though.
Behringer: TRUTH B2031A
The active speakers that are definitely worth having are those that have full DSP control over the drivers. They compensate for driver frequency response anomalies, provide RMS power limiting (lowering long-term power input if the drivers are getting warm), independent amplifier soft-clipping, active crossovers, full low-frequency driver protection (they limit above port tuning as well as below, to keep the driver in Xmax). They basically make it so that any signal you care to feed in will not kill or overload the amplifiers or drivers. Ever.
Behringer: EUROLIVE B112D
K12 Active Loudspeaker ? QSC
Chris