large bell used as musical instrument
鏞 centers on a large bell used as a musical instrument, specifically a type of suspended bronze bell.
鏞 combines 金 (metal) with 庸, which likely contributes the sound and may relate to a large or ordinary bell. The exact historical development is uncertain.
The metal radical 金 on the left suggests something made of metal, and the right side 庸 looks like a large hanging object. Picture a huge bronze bell suspended from a frame.
For ヨウ, imagine the deep, resonant sound of a large bell echoing: 'yoooouuuu' — the long 'yo' sound cues ヨウ.