Actually "close" is not subjective. Its fact. You nor about 99.9999% of the human population physically cant tell the difference between a speaker and a "live" piano if the speaker is of competent design along with the rest of the audio chain and the recording itself was also properly mastered.Hell if you were blindfolded and brought into an unknown room, of unknown dimensions and accoustic characteristics with unknown equipment in the test you would fail ANY audio test miserably on direct comparisons, so to make the earlier comment you made is absurd. If you could that would mean you would be able to tell the slight harmonic differences between 2 identical Yamaha piano's of the same model the first time you hear them. And the human ear just isnt that sensitive. Like I stated there are a few great speakers that can faithfully reproduce the sonics of the piano, or kazoo for that matter. Not perfectly, but enough so to where our ears can be the true limiting factor.
Hell I was the piano the other day, my own Grandmother wasnt sure if it was me or the audio system making the music. Granted she doesnt have the best hearing at her age, but its just a point to bring out that musical reproduction by a pair of transducers properly set up is better than what alot of folks take for granted.