I just saw this thread. I'm a university professor. I do not allow recordings of any kind during my lectures. In Missouri, Board of Regents Code of Conduct is that all classroom video recordings of all kinds not directed/recorded by the instructor are strictly forbidden and subjects the student to disciplinary action. Audio recordings are at each instructor's discretion, and we are directed to state our policy, in writing, in the course syllabus.
My advice to the OP is investigate what, if any, policies are currently in place at ISU and with your specific instructor, before diving in with any technology-aided recordings. And push yourself to take actual notes during your lectures, it will advance your learning and retention of the topic, and help you during review of your material before exams.