I think you would not leapfrog just by changing amp. Maybe mac is sweeter and warmer a bit than Marantz, but your speaker with it sleek design and its smallish woofers would never able to provide the body of sound you need to enjoy realistic classical music reproduction at home. I would rather go for an old design, if you could have an ugly big box at home, like tannoys, electrovoice, goodmans jbl studiomonitor frim the 70s 80s with at least 10' woofer. They were designed when the main source of music was analogue, and they have a more natural balance than todays speakers.