tinkling of jade or metal pendants
鏘 centers on the clear, ringing sound of small hard objects striking each other, especially jade or metal ornaments.
鏘 combines 金 (metal) with 將, which likely contributes the sound. The character is used for the tinkling sound of metal or jade ornaments.
The left side is metal 金, and the right side 將 suggests a general or leader. Imagine a general's metal pendants clinking together as he walks, producing a tinkling sound.
For ソウ, picture the sound of metal pendants going 'so' as they swing: so -> ソウ, like the soft ringing of jade.
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