This is an interesting snapshot of how the British Invasion and the bands of Britain evolved into the Rock we have today. Riding a wave of Skiffle music there, the early musicians were heavily influenced by the Blues (Root) music that came from America. Back then, it was primarily the radio that let them hear what we had. For this song, Morrison recalled fond memories of his adolescence listening to the Voice of America and hearing that music. Take a look at the lyrics This is a song about your wavelength And my wavelength, baby You turn me on When you get me on your wavelength Yeah, yeah, yeah, yeah, yeah With your wavelength Oh, with your wavelength With your wavelength With your wavelength Oh mama, oh mama, oh mama, oh mama oh mama, oh mama Wavelength Wavelength You never let me down no You never let me down no When I'm down you always comfort me When I'm lonely you see about me You are ev'ry where you're 'sposed to be And I can get your station When I need rejuvenation Wavelength Wavelength You never let me down no You never let me down no I heard the voice of America Callin' on my wavelength Tellin' me to tune in on my radio I heard the voice of America Callin' on my wavelength Singin' "Come back, baby" Come back Come back, baby… Take notice of those last few lines, "Come Back Baby". They refer to an old Blues song that was popular in America, originally by Walter Davis and covered by many artists over the years. You can read about the history of that here https://musicfor.us/2020/06/16/walter-davis-come-back-baby-1940/ I find the evolution and paths music has taken to be rather interesting and an important part of our history. I am left wondering where it will go from here.