the same that an apple has over an orange.
They are two different animals. I play my sop when I want something smooth and lyrical. This happens mostly over very delicate ballads / worship tunes. The trick with sops are to keep them in tune and NOT over blow. There is a sweet spot in the tone. Find it and you make people weep. Go beyond it and people cringe.
Alto - I can do everything I do on sop and then bust out a funk / gospe groove over top the biggest baddest worship band line in the land. You have power in this instrument as well as beauty if you know how to control your dynamics.
Peace,
Wolfram