▁are ▁sometimes ▁pl uck ed ▁by ▁fingers ▁or ▁c ym bal ▁st icks , ▁or ▁m uted ▁by ▁hand . ▁▁ 3 4 ' 4 6 . 7 7 6 " ▁For ▁a ▁P ian ist ▁ ▁Com posed ▁in ▁ 1 9 5 4 , ▁this ▁work ▁is ▁one ▁of ▁the ▁so - called ▁" time ▁length " ▁pieces , ▁in ▁which ▁the ▁title ▁refers ▁to ▁the ▁length ▁of ▁the ▁work . ▁The ▁piece ▁was ▁composed ▁using ▁chance ▁operations ▁and ▁written ▁down ▁in ▁proportional ▁graph ic ▁notation . ▁The ▁rh yth mic ▁structure ▁is ▁ 3 , ▁ 7 , ▁ 2 , ▁ 5 , ▁ 1 1 . ▁P iano ▁prepar ation ▁is ▁defined ▁only ▁by ▁specifying ▁the ▁strings ▁to ▁be ▁prepared ▁and ▁the ▁materials ▁to ▁be ▁used , ▁the ▁actual ▁choice ▁of ▁objects ▁and ▁their ▁position ▁on ▁the ▁strings ▁is ▁left ▁to ▁the ▁perform er . ▁This ▁piece ▁was ▁composed ▁for ▁David ▁T ud or ▁and ▁is ▁very ▁difficult ▁to ▁play ; ▁its ▁companion ▁piece , ▁ 3 1 ' 5 7 . 9 8 6 4 " ▁For ▁a ▁P ian ist , ▁shares ▁the ▁same ▁techniques ▁but ▁is ▁much ▁easier . ▁Both ▁works ▁may ▁be ▁performed ▁solo ▁or ▁together ▁with ▁other ▁" time ▁length " ▁compos itions . ▁▁ 3 1 ' 5 7 . 9 8 6 4 " ▁For ▁a ▁P ian ist ▁Com posed ▁in ▁ 1 9 5 4 . ▁A ▁companion ▁piece ▁to ▁ 3 4 ' 4 6 . 7 7