Blues harps usually come in different keys, that is why you see some harp players with a bandolier of harps worn like a sash. They can choose the needed key quickly. The harp can be played in the same manner without having to shift to a different start point. read more
Most harps are tuned diatonically (like the white keys on a piano), however some multi-course harps (e.g. cross-strung harps) are tuned chromatically. Diatonic harps obtain sharps and flats by the use of levers, blades, hooks or pedals (depending on the style of harp). read more