If you are biamping, you really need 2 very closely matched if not identical amps. This may also require a pre with dual outputs. Y connectors will work but not as good many times.
A cheaper alternative is one big amp vs biamping? Personally, I'd rather have 1 really good 100 wpc amp than 2 cheaper/older amps. Also, are you aware that going from 100wpc to 200wpc will only gain you 3db? That's barely audible.
A cheaper alternative is one big amp vs biamping? Personally, I'd rather have 1 really good 100 wpc amp than 2 cheaper/older amps. Also, are you aware that going from 100wpc to 200wpc will only gain you 3db? That's barely audible.