I definitely hear a difference from denon 6700 and marantz 7011 I own. I’ve noticed though that these avrs sound a little different every year though. A marantz 7008 doesn’t sound like 7013 from 5 years of tweaking.
Whats interesting to me is denon was excellent from 2005-2009 range. Clear, dynamic and powerful. Almost like you had separates when buying something like denon 5308. Then 4311 came out and sound got thicker and less clear. Maybe xt32 was at fault for most. Denon really struggled with from 2010-2014. So many bought onkyo or pioneer. These onkyos sounded absolutely better but started breaking. Then the pioneer started having ue22 errors, breaking as well. So we started buying Yamaha and realized that they sounded excellent but now we wonder what do denon or marantz sound like again.
So we try again and realize that they’ve changed again. Now they are sharper again with better clarity. They just really lack power and dynamic ability which causes extreme heat in them. So we again realize that no avr is perfect. You can spend $700 or $7000 and you’ll always find something you dislike about it.
My main room I use onkyo rz920. Secondary system denon 6700. Bedroom pioneer elite 502. Office marantz 7011. Onkyo rz720 and pioneer elite sc57 still get used in other rooms as well. Have a few more like onkyo3009, denon 4308, and pioneer sc07 in storage. I can say without a doubt denon 6700 is nice and works well but my onkyo rz920 does everything better. As far as sound quality, power and it has a better pre amp mode.
hopefully this helps