Romanus Weichlein was born in Linz from parents who were both musicians and who gave him a good musical education. He received his first musical training at the abbey of Lambach and entered the Benedictine Order in 1671. He went to Salzburg where he got acquainted with Heinrich Ignaz Franz von Biber. He returned to Lambach, and later became chaplain and musical director of the Benedictine convent of Nonnberg in Salzburg.

His oeuvre consists of twelve sonatas for strings and basso continuo opus 1 and a collection of seven mass settings opus 2. The latter collection is the source of the two masses of the second disc; the Missa Rectorum Cordium has been preserved in manuscript. The masses don't contain very virtuosic parts, with the exception of some vocal passages now and then. Polyphonic and homophonic episodes alternate, there are tutti and solo sections and instrumental preludes and interludes. Weichlein also makes use of the practice of instruments playing colla parte, for instance 3 trombones in the Missa Rectorum Cordium.

“The St. Florianer Sängerknaben is really an outstanding choir of boys - sopranos and altos - which produces a warm sound and sings with great flexibility and excellent text expression … These are enthralling recordings which show a lesser-known aspect of Austrian music-making in the time of Biber.” (musica-dei-donum)