Play F#3 and taper to a nienteĀ (gradually fading to nothing) while remaining in tune. Try rolling out the embouchure ever so slightly to pp/ppp to extend the taper even further.
https://youtube.com/watch?v=uLNvMkvn7R0%3Fsi%3DoA1O63MKaFUXWF2d%26start%3D951%26end%3D1155
If the reed goes sharp easily, cuts out at an unacceptable dynamic, or loses resonance and substance of tone, define thumbnail and taper to tip here:
If the reed requires too much embouchure to make the dynamic taper, very lightly brush the middle half of the reed (maintaining current tapers). Be careful not to weaken the reed too much.
Result of These Steps: weaker, flatter, more stable, more responsive