how to make sound shorter

[jambo222]

hi
sory abut my eng.
i have juno gi
the oboe sound is long for my use , i want to make it shorter , i trid to gange it by envelop seting but i didnt succeeded.
please halp my and explan it slow and simple,
and i need to know if thre is any softwer to edit sounds for juno gi
thnks