I filmed this with my phone. What you hear is what my phone picked up during that filming. 
      
That microphone is plugged into my computer, not my phone. The computer plays the music and I sing into the computer. After the computer records my singing, I used a little computer magic to take out the background noise, adjust the volume then shorten the video. Then I glued the finished song on to the video for the better sound quality. And of course I did the same thing with all of the other songs I did.
 

  Here's another one that I like.

  From The Movie, O Brother, Where Art Thou.