Papers, 1795-1980, mainly relating to John Roberts and his family, including papers, 1846-1888, concerning John Roberts, among them manuscript music, letters to Roberts and press cuttings; papers, 1875-1953, of, or relating to, J. L. Roberts ('Telynor Maldwyn', son of John Roberts); miscellaneous family papers, 1907-1911; stray letters, 1874-1980; music manuscripts, 1848 and undated; miscellanea, 1905-1981; and printed items, 1832-1848.

Manuscript oratorios, operas, orchestral pieces, choruses, melodies and other musical compositions (including the four Welsh Airs arranged for choir and full orchestra premiered at the Crystal Palace, 1896); an autographed notebook containing solfa versions of Welsh melodies arranged for male voices, 1915; correspondence, 1934-1935, relating to the proposed publication of a memorial volume to Jenkins by nine of his contemporaries ('Er Cof am yr Athro David Jenkins Gan Naw o'i Gyfoedion'); music exercise books, 1877-1881, and a volume containing blacksmith's accounts, Trecastell, and particulars of payments to preachers, 1796-1810.