A group of people holding music instruments.
The group of people are a band.
A group of people holding instruments are not necessarily a band, they could be casual players or a music class, for instance.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & of(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_hold(e1) & n_instrument(x4) & of(x4,x5) & n_music(x5) & (x2 = x3) & n_people(x2) & n_group(x1))
exists p1 x1 x2.(n_group(x1) & exists x3.((x1 = x3) & n_band(x3)) & of(x1,x2) & n_people(x2))