In the Welsh laws of the 10th c. which have come down to us in 12th C. manuscripts, three instruments are mentioned as used in the courts, the harp, the crwth and the pibgorn.
The harp "telyn" is the best known of Welsh Musical instruments, although it is also to be found among the Scots and Irish, as well as the Anglo-Saxons. Wales, however retained it for a longer period, and probably today the harp is more frequently played there than elsewhere. Early Welsh harps were small and are mentioned as early as the 10th C. According to Welsh law the harp was one of the three indispensible possessions of a freeman. Accoeding to Marcuse, they were originally supplied with horsehair strings but gut was the rule by the 14th c. Double rowed chromatic harps were developed by the 16 c. throughout Europe. The triple harp, used now days by Welsh harpists and associated with Welsh harping did not make an appearance until the 17th C.
According to early laws certain kinds of harps were confined to learners, and one of these kinds was made of hardened leather or was a harp covered in leather.
The other musical instruments of Wales were much the same as those in use in England, Ireland, and Scotland.
There was, however, one exception, the CRWTH, a stringed instrument that started out being plucked and was later bowed. Sibyl Marcuse in her work, A Survey of Musical Instruments, puts the Crwth in the classification of post-Medieval Lyres. Its English name by 1310 was "Crouth", and "Crowd" by the 16th century. She cites the case of a John Hogan who was reprimanded in 1537 for "singing lewd ballads with a crowd or fyddyll". According to Marcuse, by the Middle Ages it was known as a "Chorus", its Latinized form. In the 12th C. Gerald of Wales (Girardus Cambrensis) wrote that the "Chorus" was in general use in Wales and Scotland. Aimeri de Peyrac says in the 14th C. that the "Chorus" had two pairs of strings tuned a fourth apart. Marcuse cites a seal dated 1316 belonging to a player, Roger Wade which shows "a bow beside a fingerboard lyre with straight sides, rounded top and bottom, two sound holes near the lower end and -one judges- four strings". Later two more strings seem to have been added for from the 11th C. on it is referred to as having 6 strings. One poem even mentions that 2 of the strings are "for the thumb." As Marcuse points out, the 2 extra strings seem to have been drones, off of the fingerboard, that the thumb could reach while bowing. After the 16th C. the instrument is no longer mentioned. It was "rediscovered" in the 18th C. when a few people in Wales were found who still played it. According to Marcuse, the few examples that have been preserved from the 18th C. "...have an oblong body with flat belly and back, straight sides, closed at the top. Handholes separated by a central fingerboard and 2 circular holes cut in the belly; two off-board strings have been added to the 4 bowed ones, all of which are secured by rear pegs in the top." By the 18th C. the Crwth was held almost like a violin, but that is considered to be