Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
Q:1/4=100
M:4/4
K:Eb
['ed cB B>A']  
X:1
L:1/8
Q:1/4=100
M:4/4
K:Eb
"Eb" e2 d>c B3 A |"Bb7" G2 F2"Eb" E3 B |"Ab" c3 c"Bb7" d3 d |"Eb" e6 e2 | ed cB B>A Ge | 
 ed cB B>A GG | GG GG/A/ B3 A/G/ |"Bb7" FF FF/G/ A3 G/F/ |"Eb" E e2 c B>A GA |"Bb7" G2 F2"Eb" E4 |]  