The tremolo harmonica has two reeds per note, with one slightly sharp and the other slightly flat. This provides a unique wavering or warbling sound created by the two reeds being slightly out of tune with each other and the difference in their subsequent waveforms interacting with each other. These harmonicas are primarily used in ballads, folk, reggae & gospel music.
This Ferris Tremolo is double sided, with one side in the key of C, while the other side is in G.