John Barnett (1802-1890), English musical composer, son of a Prussian named Bernhard Beer, who changed his name on settling in England as a jeweller, was born at Bedford, and at the age of eleven sang on the Lyceum stage in London. His good voice led to his being given a musical education, and he soon began writing songs and lighter pieces for the stage. In 1834 he published a collection of Lyrical Illustrations of the Modern Poets, His Mountain Sylph - with which his name is chiefly connected - received a warm welcome when produced at the Lyceum on August 25, 1834, as the first modern English opera: and it was followed by another opera Fair Rosamund in 1837, and by Farinelli in 1839. He had a large connexion as a singing-master at Cheltenham, and published Systems and Singing-masters (1842) and School for the Voice (1844). He died on the 16th of April 1890.

His nephew, John Francis Barnett (1837- ), son of John's brother, Joseph Alfred, also a professor of music, carried on the traditions of the family as a composer and teacher. He obtained a queen's scholarship at the Royal Academy of Music, and developed into an accomplished pianist, visiting Germany to study in 1857 and playing at a Gewandhaus concert at Leipzig in 1860. He came into notice as a composer with his symphony in A minor (1864), and followed this with a number of compositions for orchestra, strings or pianoforte. His cantata The Ancient Mariner was brought out at Birmingham in 1867, and another, Paradise and the Peri, in 1870, both with great success. In 1873 his most important work, the oratorio The Raising of Lazarus, was written, and in 1876 produced at Hereford. Many other cantatas, pianoforte pieces, etc. were composed by him, and successfully brought out; and he took an active part as a professor in the work of the Guildhall School of Music and Royal College of Music.