Swan‎'‎s tremolo harmonicas are double reed instruments‎.‎ The bottom row of holes features the same notes as the top row‎,‎ tuned slightly higher‎.‎ This special tuning creates the tremolo‎'‎s distinct sound‎,‎ a beautiful vibrato effect with a richer tone‎.‎ These harmonicas are primarily used in ballads‎,‎ folk‎,‎ reggae & gospel music‎.‎ ‎'‎s tremolo harmonicas are double reed instruments‎.‎ The bottom row of holes features the same notes as the top row‎,‎ tuned slightly higher‎.‎ This special tuning creates the tremolo‎'‎s distinct sound‎,‎ a beautiful vibrato effect with a richer tone‎.‎ These harmonicas are primarily used in ballads‎,‎ folk‎,‎ reggae & gospel music‎.‎Special note‎:‎ multi‎-chromatic harmonica end of a putter than ordinary harmonica‎,‎ we call it change the sound bar‎,‎ met scores in semitones when playing as long as the putter went to press‎.‎ ‎(‎Press into the equivalent of the black keys on a piano‎)‎ playing without special skills to master‎,‎ just gently by hand can blow a semitone‎.‎ Chromatic 10 Hole 10 Tone ‎(‎two full octaves‎)‎