Carolan is famous for playing the harp. But what kind of harp did he play? It certainly was not the modern orchestral pedal harp! But neither was it the modern neo-Irish harp or lever-harp.
The type of harp Carolan played is nowadays referred to as the "early Irish harp". With a soundbox typically carved from a single block of willow wood, and strings of brass wire, it has a unique sound - rich, resonant and sustaining - quite different to what most people expect from a harp. Traditionally played with long fingernails, the long resonance of the strings is individually stopped with the fingertips in a complex and difficult playing technique. The early Irish harp was played in Scotland and Ireland from over 1000 years ago but died out in the 19th century. Recently there has been a revival, using replica historic instruments to play the old repertory.
There are three extant old harps, dating from the late 17th or early 18th century, that are or have been claimed to be "The Harp Of Carolan" Actually none has a good provenence, and the Carolan associations are probably 19th century romantic fabrications, but Carolan's harp was certainly very similar to these old instruments.