B Smyth

R&B singer B. Smyth is dead ... at a very young age, and after a long battle with pulmonary fibrosis. The singer's brother, Denzil, broke the news to fans ... saying Smyth died Thursday from respiratory failure and had been hospitalized for a while, struggling with his lung disease. Denzil…

Rising R&B star B Smyth -- who's worked with industry titans like Future and 2 Chainz -- has some serious balls, 'cause he told a police officer he was going to BANG HIS WIFE during a traffic stop ... this according an arrest report obtained by TMZ. According to the documents, the 21-year-old…