i haven't heard either of these, but if yure considering a change, proac recommends the arc 100.2 amp & the ls-16 or ls-25 preamp. i've heard the proac 2.5's w/the 100.2 & the ls-16, & it sounds great.
Classe vs. Sonic Frontiers
I currently own a Classe 5 Pre and power combo. I am wondering if changing the pre to a Sonic Frontiers Line 1 or greater would be a huge improvement. Also would be interested in the phono 1 to replace the internal phono in the Classe. If anyone has experience using Sonic and Classe let me know what your findings are. I am powering Proac speakers with this setup.