Do you use a Subwoofer when listening to stereo?

You push a button on the remote. I use an C2500, and a MX121, source vary from a TT, SDAC, CD, Stream, into MC275 and Class Ds, or Carys and Class Ds. Pure heaven... Easy as could be.  

Mac made a LOT of smaller monoblock... 20, 30, 40, 50, 60, 75, 100s

All were older, except the MC75, and they are still in production...

ALL of their amps are know for plenty of UMPH..

Most of music until  hip hop / rap didn't have that much sub, they were pretty much cut at 40-50 hz down, the old 78 stuff 60 hz and below.
All of my old Reel to Reel stuff is cut at 40. Big band, jazz, and country western, were all the same..

You can add BASS to the mix though...and really liven the joint up...
What most music listeners listen to is NOT sub heavy, it's bass heavy.
Subs muddy most good stereo system up because they're set WAY to high on the XO. 80 hz is the highest. Cut the bass on the mains where your subs stop.. Simple... Ya need a few though to get it Everywhere.. I don't.. Where I'm listening is just fine.
Junior (my rabbit) thanks me too. :-)

Regards

"Does excluding sub from stereo make sense?"

Only if your main speakers are full range.  

soix,
thanks.
when you transfer signal path to stereo amp, does the tv continue to display?  Very important to watch vote tallies for next 12 weeks while listening to fine music.

Why don’t you like McIntosh?

If that was directed at me, I did not say that I don't like McIntosh.  I'm not familiar with your amp, but it looks like a nice one and should have more than enough power to drive your main speakers.  If you like the amp, then get a preamp with home theater bypass.  As another poster described, it's super easy to switch between the preamp for 2 channel listening and back to the Marantz for home theater duties.

atmasphere nailed it.