It's probably a wash to a couple of hundred dollars difference between the build cost of a LFR1100 active and a LFR1100 passive. What your paying for is:
1) the time and expense to develop it and
2) the market it is trying to competing in (as Mojo mentioned) the actives are actually a value play in the high end market. It's a market catering to the few who are willing to spend a lot of money.
I just receive a pair of Actives which were damaged in transit. So I'll have to exchange them. In the mean time, since the damage is only cosmetic, I'm giving them a listen. So far, I'm fairly impressed with what I've gotten. Are they worth a 50% premium over the passives (not to mention the amp channels)? Since I've never heard the passives I can't say.
Now, people I trust tell me the passives are extremely good and there is only so much room to do better than extremely good ... I expect most of the gain to be in enlarging the sweet spot.
I can tell you that if I had to choose between passives with 4 channels of great amps or actives with 10 channels of weak amps ... I'd go passive ... the constant and dynamic power makes a very big difference.
