This sentence seems to use "~的话,..." phrase, but omit the 话. (Let me know if I'm wrong but I proceed with the assumption that it is correct).
I think that it omits 人 herehere; i. Complementing the sentence likee. 有兴趣的 refers to 有兴趣的人 (whopeople who are interested in) 可以去看看了解一下 sound. Using 人 makes the sentence more natural to meformal and polite, without it makes the sentence simpler and the meaning is still clear enough.
BTW ~的 is a common structure used instead of the referred people or things.
〈代〉 pron. 附着在词或短语之后,构成“的”字结构,代替所指的人或物。如:卖菜的;吃的