Regarding amps to drive the VR100XS. I have a pair of Double Kronzilla's and a pair of Spectron Monoblocks. I'm going to first try running my 100's full range with the Krons and then trying the Spectrons separately to get a good sense of what the 100's sound like.
I've been able to use the Krons to drive VR6's and VR5-annis comfortably. Comparing the Krons to the Spectrons full range will clarify whether the Krons have enough muscle for the 100's. I have no doubt that the Spectron monoblocks can drive them with ease since those amps, to put it mildly, are not lacking in power.
Once the full range comparisons are done, I'll try bi amping. That can be done two ways. First by the classic parallel input topology where two sets of outputs from the preamp are used, driving each power amp separately with an attenuator in front of the more sensitive amp. In my case, the Spectron needs about 4 or 5 dB of attenuation to match levels with the Kron.
The second bi amping mode is similar to what Albert does with the VR44-Aktive where a bass amp is driven from taps at the speaker input from a "main" amp being driven full range. This would utilize a single preamp output connection (balanced) to the Krons with their output connecting to the VR100's mid/tweeter input. Then a high resistance tap goes from there to an attenuator for level matching and then to the Spectrons. The potential advantage of this method is that the character of the Kron's output would be retained throughout, from deep bass on up. The Spectrons would then provide the muscle and damping factor while maintaining the signature of the input from the Krons.
This will be an most interesting and educational experience.
