S1 = Sound[SoundNote[#,3,RandomChoice[{"Flute","Piano","Tuba"}]]& /@ RandomInteger[20, 30], 8]
Export["ayse-cansu_aydede1.midi",S1,"MIDI"]

r:=RandomChoice[{1,8}]
g[x_]:=RandomChoice[{0.2,0.3} -> {x,{x[[1]]}}];
accord:=Module[{},r1=r; {{-2+r1,5+r1,9+r1},{-2,5,9}}];
scale={-2+r,5+r,9+r};
s:=g[RandomChoice[accord]]+RandomChoice[scale]
A=Table[{s,Random[Integer,3]+3},{40}];
sn[{a_,t_}]:=SoundNote[s,t];
S2=Sound[{"Flute", sn/@A},8]
Export["ayse-cansu_aydede2.midi",S2,"MIDI"]