like, admire, willingly, gladly, to quicken
歆 centers on a positive, willing reception: liking, admiring, or accepting something gladly. The sense of quickening suggests an eager, animated response.
歆 combines 音 (sound) and 欠 (open mouth, exhale), suggesting an eager, audible response such as a gasp of admiration or a willing exclamation. The exact historical development is uncertain, but the component relationship is consistent with expressing a positive, animated reaction.
Sound (音) and an open mouth (欠) together suggest someone gasping or exclaiming with admiration. Picture hearing wonderful news and reacting with a delighted, willing 'Ah!' — that is 歆.
For キン, imagine a king (キン) who gladly admires the music (音) and opens his mouth (欠) in praise: king -> キン.