Actually, the KSA80 was really rated at 100 watts, same as the 100s; they just called it the 80 to avoid confusion with their prior, fan-cooled model, the KSA100. The 100s is a bit more clinical and probably more neutral than the KSA80, which, as Sundance 45 says, is a sweeter sounding amp. Having owned a KSA 80, I can tell you that I was not at all impressed with the 100s when it came out; I far preferred the 80. It had a little bit of character, the 100s sounded a little sterile in comparison. Power-wise, I also felt the 80 could handle difficult loads better than the 100s, which was not a Class A design.
krell ksa 80 vs. krell ksa100s
thanks for any input you may give. i have b&w 801 series 3 speakers and currently using the ksa 80 amp. i will be trying out a ksa 100s in the near future. wanted to know if there is anyone out there that is familiar with the 2 amps and i am looking for any thoughts on their performace/opinions with the b&w 801 martrix3. thanks, ralph