SSSBB => very unique setting. Duo(S1,B1 or S3,B2) + Trio(S2,S3,B2 or S1,S2,B1)
bar1-9 : A Part
bar9-15 : B Part
bar15-19 : C Part
bar19-28 : D Part
bar28-39 : E Part
SSSBB => very unique setting. Duo(S1,B1 or S3,B2) + Trio(S2,S3,B2 or S1,S2,B1)