First of all, congrats on your choice of speakers...No offense, but the Sonata's will sing once you upgrade the rest of your equipment to the level of the Sonata's.
I'm not sure what your price range is, but I'm running my Sonata II's with a BAT VK 200 ss amp ($1250 used) with a Joule Electra LA 150 tubed preamp. Someday, finances permitting, I may try to upgrade to a higher end tube amp, but for now, the sound is very good once warmed up.
If you want to stay with an integrated, I would be looking @ the CARY SLI 80 ($2K used) or maybe the Cayin KT-88 ($1900 new).
I strongly recommend you stay away from mass market brands like Marantz & Denon when looking for amps. Spend a few weeks researching old links on Audiogon, and you will find many suitable options in many price ranges. Enjoy the journey.