Suggestions for audiophile grade receiver for Home theater setup

You could run the front preamp outputs from an AVR into the home theater bypass input on the NAD so the NAD would still be the only amp engaged for critical 2-channel listening and the AVR would only be handling surround processing and would power the rear speakers only.  The trick would be if you want the sub for both HT and stereo you’d need to run outputs from both the AVR and NAD into your sub, so you should check with Hsu if two inputs can both be used (seems like it should work).  Then I’d run the sub out from the AVR into that input on the Hsu and the RCA preamp outputs from the NAD into the XLR inputs on the Hsu but you’d need to buy some RCA to XLR adapters for that to work.  Again, I’d check with Hsu first to see if this setup would work with their sub, and if it does you could have a best of both worlds situation with HT and high quality 2-channel performance.  If it does work I’d recommend something like this that should be all the AVR you’d need.  Just one idea FWIW, and best of luck. 

https://www.accessories4less.com/make-a-store/item/yamrxv6a-rb/yamaha-rx-v6a-7.2-ch-x-100-watts-8k-a/v-receiver/1.html

Anthem. 

Hello and Happy Thanksgiving to all. I’ve been very pleased with my Anthem MRX  1140 8K for my home theater rig. Excellent build quality, power  brings theater like sound (depending on your speakers set up, of course).Also the SQ is superb.  Only drawback is the included remote control which is no where near the quality  of the AVR. Not a problem as I use the Anthem remote control app on my phone. (BTW after speaking with Anthem customer service after encountering some initial WiFi connection issues with their remote  control app I now disable my VPN and the app works perfectly. Just reenable VPN when done with the MRX. Let me add that the MRX series is as good as some brands/units that sell for twice the Anthem price. 
Enjoy the music. 

I have the Integra DRX-8.4 and it's great.  But I would recommend getting a separate AV processor and amplifier (like Buckeye).  Easier to upgrade one or the other, or replace one if it dies.

Think about a Marantz AV pre-processor and separate power amplifiers.  I use a 2-channel Krell for my main speakers, and a six channel Perreau for the rest.  No centre channel for me!