If you look at the integrated amps section of the forum, you will find a lot of stuff already discussed, and some very helpful opinions. A lot of footwork already done. Are you happy with the speakers?
My BIL has had those same speakers, I do not know anyone else with them, thats why I asked. He ran them for years with a Pioneer receiver and it made awful music. Then he got a Nad 325BEE and things changed dramatically. I pulled the speaks another foot from the rear wall and toed them in a bit.
It worked out very well.
If I can convince him to get a 542 cdplayer, it should be complete. No sub required.
I had a pair of XTi60's driven by my Marantz SR 7300 (still do, they are for sale). Had a Marantz cc4300 and earlier a Yamaha cd changer. It was okay, the speakers needed to be away from the wall and toed in, and were definately in need of a better source (like the C542). While the Marantz was okay to drive them, I agree with Nuck, I think a NAD amp would have been better . Btw, my B&W 602S3's clearly outdo the JBL XTi60's and yet were just a little over half the price (without stands). I know the 80's are a step up, and the XTi's had a lovely finish, but they are a bit finiky. I think more power is a good thing for your 80's. If you could try a NAD C352 or C372, I think you'd be in the ballpark.
Naim. They present music in a different way. Imaging? Nope. Soundstage? Depends on your room. Straight up? yup. The Naim stuff can flat earth the heck out of near anything, and make you believe it.