為何麥克風要倒吊？

http://www.prosoundweb.com/channels/recording/4-good-reasons-for-hanging-your-microphone-upside-down/?eid=341034799&bid=1636829&utm_content=buffer2735e&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer

當年是因為真空管太熱，怕影響振膜...