Hi Lipe
I have the Lyngdorf TDAi 2200 driving my Linn 212's ,and Primare amp in my surround sound.Both should go really well with your ATC's( great speakers ) but the biggest difference comes when you use the built in Room Perfect in the Lyngdorf.Takes about 15 mins with the supplied mike to measure your room and tailor the sound to it .It then gives you 3 settings at the push of a button ,one for your listening position , a global one for best sound all round , and one to remove any correction.Significantly I used the latter button once to check the sound and have always kept the correction in.It enables me to have a rear ported speakers in the corners of my rather awkward room without any boom.Don't buy the Lyngdorf without it ,but either of your choices will sound fantastic.Regards,David