Why are the Infinity IRS, Reference 1b, Beta ect speakers passive on the mids and highs?


I would like to know why all of the classic Infinity's and most other brands use passive crossovers for the mid to high transition? I don't think it was for cost and that level. Is passive better? Has anyone compared both to know which is better?
partroysound
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Hi timlib
The Richter scale crossover is changeable through a chip. I have lots of values for it. You can even make your own crossover point, they give a formula in the manual. The other audio control is not an epicenter, I made a mistake but it uses the same crossover as the richter so using the two I can get a 3 way at any point I want. I am glad you have some respect for the Nakamichi, I wasn't sure what you would think about mixing car audio .I haven't tried using 4 amps at the factory crossover points. If I do I will let you know. Setting levels isn't a problem as I have an Audio Control 3050A spectrum analyzer. I am still not sure using so much electronics in the signal path is the best route to go. I really appreciate your help.
Marc
Not sure If I can add much to this discussion but active crossovers would have been more expensive at the time. The system was already expensive when you add the amp and other requirements. I own two sets of the RS1B woofer towers and the servo controller. These parts are getting old and my servo now has a low level hum that it didn't have before. I now use an active crossover without the servo system and get very satisfactory results. The RS1B was a great system but after listening to the Infinity Emits and Emims for the last 4 decades I have moved on.  
One of my best friends on the planet is an old timer very respected figure in the audio world.  He uses a 12v crossover with a passive sub, of course, he modded it with some nice parts and built a fully regulated 12v supply, but it does a great job.  Years gone by, I worked for Orion. I've heard of few of their amps in home use and at one time I owned a stereo store,  we did 12v to high end...and there,  we tried a soundstream amp with some home gear... I've seen very respectable results mixing.... Never true hard core audiophile with the amps, but some truly respectable results.