Honestly with those speakers considering the pricing of what you are looking to spend on a used amp, I would now highly suggest just looking at the Mcintosh integrated amps which will get you the full spectrum of sound for the type of music and warmth you probably seek, and get a much better synergy due to having the built in preamp, also if you need them "Tone" controls, Legacys are pretty easy to drive from what I remember and the kevlar mids with ribbon tweeters would really be more at home with the mcintosh sound in my opinion...
Again I would shoot for a integrated, this difference due to your adcom preamp would be more bang for the buck I think, as a matter of fact your preamp alone might be more effective to replace than the amp all together. I would look at a used like mcintosh 6900, it will be the swiss army knife all in one that should give you almost all you will get from those speakers, and its better than adcom gear honestly, you could even go local and find many mcintosh and krell dealers to try at home on your speakers first, then buy.
