If you don’t mind, I’d like to take a stab at this question you have. Yes it definitely has a unique sound, the chinese R that is. It’s almost like a cross between the letter r and y. Like in the word "ren, like in “ren shi ni”, the ren actually sounds like(ryun, but the y is emphasised very slightly.) I hope this helps. I still have to practice it because I don’t sound chinese enough for me.