Correct me if I'm wrong, but the 3/4 is the most common size bass, esp. in jazz circles, and the 4/4 is for more orchestral work. If someone is tall, but wants to play jazz, would you recommending hitching up the 3/4 or getting a 4/4? And other than the 4/4 being obviously larger, and perhaps a little louder, is there any other real difference? *confused* Thanks guys!