How loud the level is using test tones will be receiver or processor dependent but typically they are 75 db's. 85 db's should be how loud the dialog or normal sounds are while listening at reference levels.
Music does not have a reference levels that I know about.
"Natural stage spl" is going to be all over the map depending on the kind of music with a lot of it in the "hearing protection is seriously advised" range. Way past what is comfortable to listen to at home for any period. Just pick whatever works for you.
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