Grammar question: heard of or about

" heard of" refers to general events or things whereas " heard about" is more specific .e.g: I heard about the fight last night.

These are phrasal verbs. "Heard of" shows you know the existence or name of the bar, while "heard about" shows that you know some more information of the bar.

Heard of → recognition

Heard about → detailed information

Both would be suitable and it depends on what you want to communicate! To hear of something is used to communicate being aware of its existence whereas to hear about something refers to learning specific details of that something.

1. "of" would indicate you did not know about its existence

2. "about" would be more about its characteristics as a bar . . . You may know it exists but have never been there or been told anything about it. So let's change the sentences a little: I don't know (anything) about that bar. I don't know of that bar (first time of hearing).