ATC SCM40

I recently posted my experience auditioning the active version of these speakers and loved them.  John Rutan at Audio Connection in Verona, NJ has both the active and passive versions on the floor.  I think the actives sound much better, but they are also about $5k more.  Of course, you could then sell your amp.

I owned SCM40 passive speakers for a while and then upgraded to the SCM50ASLT active speakers. Like many others, I prefer active ATC speakers.

After trying a number of tube and solid state amps with the 40s, I found the Coda Continuum No 8 stereo amp to sound the best in my room to my ears. Manley Snapper mono blocks also sounded very good.

At the Arizona Audio Video Club Speaker Fest in 2019, ATC SCM40 passive speakers with ATC electronics won by a wide margin against seven other well regarded speakers.

Sorry, I have no experience with the OP's Adcom amp.

vinylvalet we are a coda dealer and the coda does sound amazing with atc 

we have experience with adcom and vandersteen 

Dave and Troy

Audio Intellect nj

Atc dealers

If you plan on using the 10x9 room(system post) the ATC SCM 19v2 would be a better choice. I would also upgrade the amp/preamp.

As far as sensitivity goes, you do need a minimum of 120 watts for your amp and 150 is probably a better low end cut off. I drive mine with a Musical Fidelity A308 integrated and it seems to be a good match for my taste. Others would recommend something warmer. The consensus is that the active version is superior, but if you already have an amp and can swap for another amp, it’s a lot more expensive.