It goes without saying that to play low notes softly, your saxophone must be well constructed, free from leaks and properly adjusted. Pads that leak will make playing low notes softly on the saxophone very difficult. ... If the saxophone timbre or resistance changes at all, you will need to adjust the G# mechanism.
Why is my saxophone only playing high notes?
Assuming the issue is not the player, the most likely causes of a saxophone only playing high notes are a leak in the instrument or an octave key that is stuck open. ... In both cases, however, you should take your saxophone to a specialized repair person.