Reversing the usual cliché, he was the son of musicians and teachers, but initially studied mathematics at Colorado College, receiving a BA in 1935, before deciding to follow in his parents' footsteps.
[2] In 1945 in Paris, Effinger conceived the idea of a music typewriter, and by 1947 had developed a rough prototype.
In March 1954 he patented his machine as the "Musicwriter", and exhibited his first production model in July 1955, in Denver.
[3] He also invented a device to accurately determine the tempo of music as it is being performed, which he called the Tempowatch.
[2] Choral works figure among his most popular compositions, several of which are large scale and based on sacred subjects, including especially Four Pastorales for oboe and chorus.