instrument
錞 is a rare kanji referring to a type of musical instrument, likely a bell or metal percussion instrument. Its meaning is narrow and specific to that object.
錞 combines 金 (metal) with 享, which likely contributes the sound. The exact historical development is uncertain, but the structure suggests a metal instrument.
The left side 金 means metal, and the right side 享 looks like a stand or a bell shape. Picture a metal bell resting on a stand: that is the instrument 錞.
For シュン, imagine the sound of a metal bell ringing: 'shun!' The sharp, metallic 'shun' sound cues シュン while the bell is the instrument.