I've been testing a bit today and I can't quite figure out what's going on.
On movies it looks like -12 db is high enough for me (XT 32 set to Reference and Dynamic equalizer set on, reference offset 0). Here I have a wide margin in other words
On multichannel music I turn it up to about -2 to get it (really) loud. Probably safe
But on music in stereo (from the Bluesound Node, connected with optical) I have to set it around +6db to get to the upper listening level I use (factoring in that I have raised to source level on the input with +6, so 0 on the master level). On the Apple TV 4 (hdmi) I also have to turn it up to those levels to get the right omph
This is probably because the power amp has an input sensitivity of 1,7V?
Although, if I stream music from the inbuilt airplay on the Denon, -10db on the master volume it is plenty loud. Makes me wonder if it all has more to do with the output levels from the Bluesound and Apple TV or the input sensitivity on the X3300.
It's strange because the power amp is a Marantz PM11S3 with ht-bypass and that on its own has no problem driving our front speakers to a thunderous level. There's no problem playing a cd at 100db (peaks) if I play it through the Marantz directly (and that's without subs), but if I play it through the Denon (with subs) I only get about 90 db when the master level is at 0db. With "overdriving" to 5db I get the level that I would expect (or a little less).
Please note that I don't listen to music that loud for long, but it's nice to know that the headroom is there
From what you write about the results from your extremely kind and helpful testing I ought to get high enough voltage to drive the Marantz power amp fully with the Denon master volume below or around 0db, but somehow I don't. It's all very confusing
Thank you again so much for testing and for helping me with this! It's so kind of you and I truly appreciate it!
Sorry about this very rambling post, I guess it is as confused as I am