Once upon a time, admittedly some years ago, I sold McIntosh stereo equipment. Their quality of McIntosh gear was very high then, and if anything is perhaps a bit better know. Without actually hearing the 2205/6100 combo vs. the 6100 alone, it's really hard to know if there will be an improvement in the sound. There might be an improvement if you were using really inefficient speakers, but the Klipsch Fortes do not need a lot of power to drive them. Hence, I am inclined to doubt that you will hear much difference by moving to the 2205 as your power amp.
I also sold Klipsch speakers in the early 1990's, and am very familiar with the Fortes. To be honest, if you want to improve the sound of your system, I recommend you upgrade your speakers before doing anything about your amplification chain. The Mac 6100 is a very good unit, and I doubt you are hearing it to the best advantage with the Forte speakers.
I also sold Klipsch speakers in the early 1990's, and am very familiar with the Fortes. To be honest, if you want to improve the sound of your system, I recommend you upgrade your speakers before doing anything about your amplification chain. The Mac 6100 is a very good unit, and I doubt you are hearing it to the best advantage with the Forte speakers.