Bring self taught, I have gaps in my musical theory knowledge. I’m looking for a systematic exposition of basic rhythmic concepts (time signatures, how to read rhythm, etc.) to make sure I missed nothing, to count music more efficiently and to broaden my horizons. It can be a video, a book or a course, as long as it is efficient in its exposition (i.e. not a 800 page book). Any suggestions would be super appreciated. Thanks !