|  For
        
        playing  traditional Scottish and Irish music, the tremolo
        harmonica is the choice of many musicians. These are
        diatonic harmonicas constructed with double holes, each containing two blow and
        two draw reeds.  Each pair of reeds is tuned to the same note,
        however, one is tuned slightly higher than the other.
        When played, both will sound together and the slight difference in
        tuning creates a vibrating or tremolo effect. This effect sounds a
        little like an accordion, a tone that is particularly suited to jigs,
        reels, polkas, and other traditional dance tunes. Tremolo harmonicas are not
        made to play the blues because bending and overblowing are  difficult. Octave harmonicas are similar to the tremolo models, but
        the pairs of reeds are tuned an octave apart. The resulting sound is
        full-bodied and strong, but without the tremolo effect. |  |