Read this on an fb page.
"君はもっと自分の 声の凄さを知るべきさ..."
Does it mean "Like I need to know more in how great your voice is."? Or "Like you need to know more in how great your voice is.""
Am I right in assuming "知るべき" describes how great her/his voice is?
Read this on an fb page.
"君はもっと自分の 声の凄さを知るべきさ..."
Does it mean "Like I need to know more in how great your voice is."? Or "Like you need to know more in how great your voice is.""
Am I right in assuming "知るべき" describes how great her/his voice is?
べき is "should". See: How to use べき ( = beki)
Therefore 君はもっと知るべきさ is "You should know more". さ is a sentence-end particle. And the object of 知る, marked with を, is 自分の声の凄さ, "the greatness of the voice of yours".
君はもっと自分の 声の凄さを知るべきさ。
You should know the greatness of you voice more.
You should be more aware of how great your voice is.
No, it's not like you say. 声の凄さ is the part where the voice is described as great. 知るべき means "(you) should know/understand".
君はもっと自分の 声の凄さを知るべきさ...
My understanding by reading this sentence without context, is as follows: someone (the listener) has a great voice but maybe he/she is not aware/underestimates his/her ability. Therefore, the speaker tells him:
You should know/understand more (be more aware of) the greatness of your own voice
Basically the speaker is telling someone that he/she has a great voice but doesn't seem to realize it.
You should look more into べき, for example here. In two words, is a way of expressing "should" in English.
The basic construction is: Verb-dictionary form + べき/べきだ (with exception for する => すべき/するべき).
Simple example: 約束は守るべきだ (you should keep your promises).
Final note: the ending さ is a colloquial way to make a statement more assertive. See for example this question.