harm onic . ▁It ▁premier ed ▁April ▁ 2 1 , ▁ 1 9 6 1 ▁in ▁Ven ice . ▁Another ▁performance ▁occurred ▁at ▁Wars aw ▁Aut umn ▁in ▁ 1 9 6 1 . ▁ ▁Ven et ian ▁Games ▁is ▁usually ▁considered ▁the ▁first ▁piece ▁of ▁L utos ław ski ' s ▁m ature ▁period . ▁In sp ired ▁by ▁John ▁C age , ▁Ven et ian ▁Games ▁is ▁notable ▁for ▁its ▁use ▁of ▁limited ▁ale atory ▁techniques . ▁In ▁Ven et ian ▁Games , ▁L utos ław ski ▁determined ▁the ▁overall ▁form ▁and ▁harm onic ▁boundaries , ▁yet ▁he ▁left ▁the ▁real ization ▁of ▁the ▁exact ▁cont rap unt al ▁and ▁harm onic ▁details ▁up ▁to ▁chance ▁in ▁performance . ▁The ▁ind et erm inate ▁character ▁produces ▁ale ator ic ▁counter point , ▁which ▁is ▁a ▁type ▁of ▁sound ▁mass . ▁ ▁The ▁score ▁of ▁the ▁first ▁movement ▁contains ▁eight ▁box ed ▁musical ▁events ▁l abeled ▁A - B - C - D - E - F - G - H . ▁Se ctions ▁A , ▁C , ▁E , ▁and ▁G ▁function ▁as ▁a ▁ref rain . ▁Four ▁per cussion ▁instruments ▁signal ▁the ▁beginning ▁of ▁these ▁sections , ▁which ▁are ▁composed ▁of ▁l ively ▁un - meter ed ▁lines ▁played ▁by ▁wood w inds . ▁Each ▁subsequent ▁ref rain ▁adds ▁instrument ation . ▁Thus , ▁Section ▁C ▁util izes ▁wood w inds ▁and ▁ 3 ▁timp ani ; ▁Section ▁E ▁util izes ▁wood w inds , ▁ 3 ▁timp ani