In this episode of But Why, we’re answering your questions about…us! Why do you make But Why? How are podcasts made? And we’re answering questions about the physics of sound and radio. What is sound and how is it made? Why are sound waves invisible? How do echoes work? How do microphones work? How do radio signals work? Answers to your sound and radio questions from our VPR colleagues: sound engineer Chris Albertine and Chief Technology Officer Joe Tymecki.