Josef Rheinberger (b. 1839, d. 1901) was a prolific composer in almost every field, but he found in the Organ the medium best fitted to his genius and temperament. This seems to be proved by the fact that his reputation as an Organ composer has grown and is now firmly established, whereas his position in other branches has declined. His twenty sonatas and his numerous shorter pieces (about a hundred) make up one of the most important contributions to the Organ repertory. It may indeed be claimed that, in the maintenance of a high level of quality and interest throughout a long series of works of both large and small scale, his position as an Organ composer is second only to that of Bach.
Sonata No. 19:
The G minor Sonata is one of a small proportion of the twenty - No. 15 in D is another - concerning whose merits players are divided. It does not meet one half-way. It is the longest of the twenty: some monotony inevitably results from the use of the key of G for all its movements : its difficulties are of the ungrateful type : and the vigour of its first movement is often rough-even harsh. Yet it appears to be among the favourites of those who know it well; the late Dr. G. J. Bennett (a pupil of Rheinberger's, and a devotee of the Sonatas) placed it among the best of the later numbers.
Sonata No. 20:
In spite of some inequalities, No. 20 makes a worthy end to a fine series. Rheinberger's failing health at the time of its composition is no doubt responsible for a few moments of indecision, especially in the Finale. The invention shows little, if any, falling off. In all the sonatas there are few better themes of the broad diatonic type than that which opens the first movement ; and the pleasant tunes of the Intermezzo and Pastoral, and the swinging subject of the Finale are in the true Rheinberger vein. But the lack of a substantial fugal section is felt: it might well have come as a central portion of the Finale, which would then have been a capital example of the Grand Chreur type so well managed by Guilmant and other French composers.