I replaced my 100C with a 200C for use with a pair of bi-wired 104/2s to good effect. My proceed pre-amp generates white noise for use when balancing speakers, and the quality of the sound is remarkably uniform across the three speakers. We preferred listening to a DVD of the Barnford Marsalis Quartet in PCM stereo, because the 100C didn't match the 104/2s in Dolby 5.1, whereas the 5.1 version is the winner with the 200C in place.
Both the 100C and 200C have Uni-Q HF drivers; the 104/2s have dome HF drivers.
Surrounds are 102/2s. The sub is a Velodyne HGS-10 with crossover set at 50 Hz that sits of an Auralex SubDude). The Proceed amps can deliver 200 watts per channel into 4 ohms, and are used with Proceed pre-amp and digital signal processor (PAV/PDSD) front end. (I intend to add a second HGS-10 that will sit on a SubDude.)
This is a fine sounding system for music, movies, or HDTV. I highly recommend the 200C for use with a pair of 104/2s. The 100C is a perfect match for 102/2s, but not for the 104/2s. I've never heard the 90C.
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