This Anthem MRX1120 is a big step up all around and is below your budget. It also includes their excellent ARC room correction software.
Best of luck.
Curious question. If you already have a Monolith amplifier, why are you looking for an AV "receiver"? A preamp/processor would be better.
The Marantz processors have some of the most natural sounds since they use discrete analog output stages, but they do have a slight roll-off in the high frequencies. This could compensate for your harsh system sound. The used Marantz AV770x series are in your price range.
Sorry I used the wrong terminology, indeed I’m looking for an AV processor. I realised this when soix pointed me to a device that had built in amplifier but the website isn’t letting me edit the title of my original post.
After realizing this I did start looking at the Anthem AVR line (rather then MRX), so it seems my choice is between Anthem and Marantz. Anthem seems to be overall getting better reviews and I could always tailor the sound to my liking, but Marantz might be a better match for my particular setup and the old school in me likes the idea of listening to a system without any equalizer / tonal adjustments. I think both options will be a big step forward. I’m also not planning on any more upgrades for some time other than keeping upto date every several years with av processors and video standards.
The Marantz 7705 seems very good value for money?
Marantz 13.2 says make offer
Marantz, 11.2, New (open box?)
Marantz, NEW, make offer
I much prefer bypassing as much sound processing as possible using “direct” / “straight” modes tbh. I’ll turn the question around, if you’re buying high end gear why would you then put the signal through such artificial circuitry vs buying components that naturally give the sound profile you want allowing you to bypass it?