Are you some sort of child? I’ve owned 618B’s over the years. They were never mic transformers. If you don’t agree then keep it to yourself until you figure out what you’re talking about. So many people on here act like they have the last and only word on it. Personally, go ahead use em as mic transformers, until you find out they’re not suitable.Nope. Do the research. Yeah, the Asian hifi people use them for that.