Here is Sometimes I'm Happy, a song in Joni Mitchell's album ''Both Sides Now'', arranged by Vince Mendoza. http://www.deezer.com/listen-780634
The intro is in Abmaj.
Do you hear that funny dissonance? You can hear it 3 times at 00:04, 00:08, 00:12.
I hear that it's the middle voices that are making that sound, but I can't figure out which instruments and what notes they are!!
Any help?