Yes, full orchestral is the real test for a speaker (solo piano too). Most box speakers get bogged down under the pressure. Dipoles handle it better than most, such as, panel, electrostatic, or the rare open baffle dynamic speakers, by eliminating cabinet resonances. As Shadorne mentioned, dynamic range and transients are critical too. Larger speakers usually handle this better, but that also depends on the quality of the drivers and other factors such as the Qts. Very few speakers do it well.
Another factor is how the speaker interfaces with the room. Poor off-axis response causes a dull reverberant field. The very nonlinear reflected sound throws the whole 'picture' off.
Another factor is how the speaker interfaces with the room. Poor off-axis response causes a dull reverberant field. The very nonlinear reflected sound throws the whole 'picture' off.