Max Reger (19 March 1873 – 11 May 1916)
German composer and organist.
This piece comes from his 30 Kleine Choralvorspiele, Op.135a. Simple little piece on the advent hymn which uses the same maunal all the way through. Calls for F dynamics to start with and ends on FF. I did this by adding the Recit Trompette, Clairon and Plein Jeu at the end to the 8' + 4' foundations coupled to Positif Trompette.
The score can be found on IMSLP:
https://imslp.org/wiki/Special:ReverseLookup/534665
Hope you enjoy.
John