I'm just jumping in here... been gone a long time.

As far as the apartment layout goes - I lived in a 1930's apartment in Houston that had a very similar layout, and I was told that the kitchen door to the hallway was a "servant's entrance." Don't know the veracity of that claim... but that building was definitely built in what would have been a very well-to-do area in that time. The kitchen also had a cool little mini-door for milk delivery that I thought was very cool.

As far as the sibilance...

I find that DOES have a lot to do with source.

CDs tend to be more sibilant than LPs for me, but I think that has to do more with the target audience of the mastering engineer.... CDs gotta sound great on all kinds of crap, but people who are buying LPs in this day and age are generally "paying more attention." This may have a lot more to do with the LP cult crowd than actualy quality of the medium... but I'm a pragmatist - I like the LP sound, in whatever bias it comes wrapped in.

Also - the performer/recording engineer can have a lot to do with it. I've got a friend in a major label rock band... and I know he just sings WAY too close to the microphone, and it's just really obvious THAT is the recording - the SSS'es are practically set fire!

I think that if you find a wide variety of source material to be too sibilant, or if you hear the sharpness as a mild "echo" - like an mp3 artifact - then it is probably your room or sensitivity to those frequencies. If it's really directional and isolated to a few things... well, that's just the recording (and life).

I hope I helped!