Sound, neutrality and the pursuit of everything

I'm after the most transparency I can have in an apartment.

It has to sound good at moderate listening levels and be so clear and lack distortion that I feel like you do when you are at the top of a mountain range, like you can see for miles, only with your ears.

Re-creating a live rock n roll performance is most definitely NOT my goal.

This part of Erik's post pretty much sums up where I'm at after years of pursuit, but it wasn't always this way. My taste in music has evolved over time, goal posts have shifted as I've aged and gained experience. Small Jazz clubs have replaced deafening Rock concerts. At home it's much of the same, mostly Jazz (lots of classic 50's and 60's recordings, piano trios, late-night smokey lounge, and moody Nordic stuff). Moving to a fleawatt SET/high-efficiency speaker system with its gorgeous clarity and tone has proven to be just about perfect for me now. Doubt it would have satisfied in my youth.

Folks, I really enjoy everyone's approach to this, so thanks for commenting. For once, there is not post touting "absolute knowledge" on a topic, or condescending comments. It's refreshing!

My purpose for the post was to see how different people approach the "quest" of this hobby and, even though the answers are highly personal, it does give some insights into what people are looking for. 

Thanks again (and keep'em coming, this is fun to read)

The terms "neutral" and "transparent" are abstract in the context of sound reproduction. Unless you talk about a gear selector or a physical material, like glass, for the latter; these terms are open to personal interpretation - as they should.
Going back to the OP's reference to the Dianna Krall performance. Even if you assume the sound crew nailed it for the live audience there are so many other variables at work in the recording process for that performance.

Microphones, cables, sound boards, tape decks (or discs), etc. that endeavored to capture what the audience heard - or what the recording engineer decided was optimal (to their ear). What if the recording did not sound exactly like the live performance? So what. Does it please you? My goal is to listen to music I enjoy on a system that helps me enjoy the music. If I don't like the sound then what else matters? My circus, my monkeys.

The pursuit we engage in is to put together a system that pleases us relative to the environment we listen to our music in.
You really can't achieve that completely by grasping at equipment that claims certain specifications or measurements.
You may get closer to your ideal by targeting equipment that you believe will deliver but the only true test is to acquire and listen for yourself - in the environment that matters to you.

Frustrating at times but fun more often than not.