are a type of harmonica
, distinct by having two reeds per note. In a tremolo harmonica the two reeds are tuned slightly off a reference pitch, one slightly sharp and the other slightly flat. This gives a unique wavering or warbling sound created by the two reeds being not exactly in tune with each other and difference in their subsequent waveforms acting against one another. The degree of beating can be varied depending on the desired effect. Instruments where the beating is faster due to the reeds being farther apart from the reference pitch are called "wet", whereas those where the beating is slower and less noticeable due to the reeds being more closely in tune are called "dry".
" is most often defined as a periodic change of volume (sometimes incorrectly defined as a change in pitch, strictly vibrato
). Most orchestral instruments achieve this effect by repeated playing of a single note. The tremolo harmonica achieves the effect by employing the physical phenomenon called beats
. Each note is played simultaneously by two reeds, fractionally out of tune with each other. The resulting sound is of constant pitch but the volume oscillates between loud and quiet. This effect is fairly common amongst Western
free-reed instruments and is found in accordions, harmoniums and reed organs under various names (celeste, vox jubilante, etc.), but it is also used, for example, on the piano, where each... Read More