Construct a musical piece by amalgamating the designated alphabetical representation and the supplied musical theme.
X:1
L:1/4
M:6/4
K:Bb
['g/ f', 'f2 f f3/2 g/ f g2 a']  
X:1
L:1/4
M:6/4
K:Bb
 F | B3/2 A/ B c3/2 d/ e | d B2- B2 d/e/ | f3/2 g/ f A2 B | c3- c2 F | B3/2 A/ B f3/2 g/ f | 
 g a b a3/2 g/ f | (g c f) f2 =e | f3- f2 |] f | f3/2 g/ f g2 a | b d2- d2 d | e3/2 f/ e d e c | 
 g3- g2 f | (e f) d (c d) B | A B G F2 a | (g/a/) b G A2 B | B3- B2 |]  