lol, notmally clarinetist don`t use vibrato at all. you may use it at a higher level played classical, but in general vibrato is for flute, sax, trumpet, and a few others. if you quiver when you play, just work on long tones keeping a firm embousure and tight corners, and a flat chin and as your mouth becomes stronger you will stop quivering. imho clarinet doesn`t need vibrato to make the sound better, we play such a beautiful instrument when played correctly
~Shanna