I'm not very technical, but here's ATC's claim:
" Active filters allow independent control of level and phase(time). This is not possible with passive crossovers. With a passive crossover any changes you make to the circuit affect both level and phase. The benefit this allows is that we can adjust for the crossover to have a perfect magnitude response and phase response. The result is that the stereo imaging is much more stable and the tonal balance of instruments is improved. "
At any rate, as I said, I've heard the active and passive versions of the same KEF, and it's night and day. And generally, I think the amp-load matching opportunities in active designs eliminate/optimize much of what people hear as differences in expensive amplifiers, right down to the driver level. I remember that Julian Hirsch's infamous blind A/B/X amplifier listening test involved a mediating gain/impedance-matching step that probably fouled the experiment, but I could be wrong. (ducking away from object thrown by amplifier mavens). I also run balanced, and like the idea of going balanced to the speakers.
" Active filters allow independent control of level and phase(time). This is not possible with passive crossovers. With a passive crossover any changes you make to the circuit affect both level and phase. The benefit this allows is that we can adjust for the crossover to have a perfect magnitude response and phase response. The result is that the stereo imaging is much more stable and the tonal balance of instruments is improved. "
At any rate, as I said, I've heard the active and passive versions of the same KEF, and it's night and day. And generally, I think the amp-load matching opportunities in active designs eliminate/optimize much of what people hear as differences in expensive amplifiers, right down to the driver level. I remember that Julian Hirsch's infamous blind A/B/X amplifier listening test involved a mediating gain/impedance-matching step that probably fouled the experiment, but I could be wrong. (ducking away from object thrown by amplifier mavens). I also run balanced, and like the idea of going balanced to the speakers.