premise: a man with beard sitting down playing an acoustic guitar.
hypothesis: The band sets up their instruments.
explanation_1: A band is a group while a man is a single person, also while the man is playing an acoustic guitar, the band sets up their instruments.
explanation_2: He refers to a man, not a band. Also, a guitar is one instrument so you can't pluralize a single instrument.
explanation_3: A man sitting down playing acoustic guitar is singular and specific, while band sets up their instrument is plural  and vague.
premise_logic: exists e2 e1 s1 s2 x1 x2 x3 x4.(a_topic(x1) & for(e1,e2) & Theme(e2,x4) & Actor(e2,x3) & v_play(e2) & n_guitar(x4) & a_acoustic(s2) & Theme(s2,x4) & a_down(s1) & Manner(e1,s1) & Actor(e1,x3) & v_sit(e1) & (x1 = x3) & with(x1,x2) & n_beard(x2) & n_man(x1))
hypothesis_logic: exists e1 s1 x1 x2.(n_instrument(x2) & of(x2,x1) & n_thing(x1) & n_band(x1) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_set(e1))
premise_sim: exists e2 e1 s1 s2 x1 x2 x3 x4.(with(x1,x2) & v_sit(e1) & v_play(e2) & n_man(x1) & n_guitar(x4) & n_beard(x2) & for(e1,e2) & a_topic(x1) & a_down(s1) & a_acoustic(s2) & Theme(s2,x4) & Theme(e2,x4) & Manner(e1,s1) & Actor(e2,x3) & Actor(e1,x3) & (x1 = x3))
hypothesis_sim: exists e1 s1 x1 x2.(v_set(e1) & of(x2,x1) & n_thing(x1) & n_instrument(x2) & n_band(x1) & a_up(s1) & Theme(e1,x2) & Manner(e1,s1) & Actor(e1,x1))