Gullahisland points out that there are many overtones resonating when a piano is played. To discern the sonic character and personality of the instrument, the timing has to be dead on and the speaker has to recreate the reverberant sound field to endow the reproduced sound with the vibrancy and harmonic richness you immediately recognize as live sound. Additionally, accurately reproducing the size and sound of the body of the instrument and conveying venue information (hall sound) well requires good extended bass response which must blend seamlessly. There are few loudspeakers which successfully do all of this. In my experience and opinion full range dipoles do it best.
