Manhattan College of Music professor and Skilled double bass player Timothy Cobb instructing a bass lesson within the late 2000s. His bass features a small C extension by using a metal "equipment" with buttons for playing the pitches around the extension. You may as well insert a youtube hyperlink (URL https://lindgreen-raahauge.blogbright.net/the-chief-the-numbers-to-mp3juice-popular-music-downloader