Guest article by Jeffrey Ostrowski
The Missa Pro Defunctis, in particular, was always set to organ accompaniments. Not atypical is this 1876 Requiem Mass accompaniment (click to view) by Dr. Franz Witt. In his 1910 edition, Max Springer carefully marked all the Sundays of Lent, through Palm Sunday (click to view) with "Non pulsantur organa" . . . yet still harmonized each and every chant. For the Sundays of Advent (click to view), Springer put "Silent organa."
For those interested, this longer article has extremely rare excerpts of 19th century organ accompaniments, explains the different "schools" of Gregorian accompaniment, and contains many more instances of "forbidden" accompaniments (like the Pater Noster, Preface, etc.).
I would like to share a few "tricks of the trade" of Gregorian accompaniment, but I'm a bit nervous. After all, Bishop Fulton Sheen has reminded us that "ordinarily, the less your audience understands, the more impressed they are with you." Still, I feel that giving away these "secrets" might help people who are interested in music but "don't know much about it" get a glimpse of compositional techniques. (Perhaps some of the fantastic visual artists on NLM will be inspired by this article to reveal some of their "tricks" as well.)
It's important to approach each piece differently, because each piece in the Gregorian repertoire presents unique challenges and deserves careful consideration. In general, all harmonizations will require four things: (A) chordal direction (that is, "go somewhere"); (B) as much (modal) chordal variety as possible; (C) counterpoint and smooth voice leading; and (D) variation in texture. I cannot (in this short article) explain each of these terms, but I will give a quick definition of "counterpoint." Wolfgang Mozart said, "Counterpoint is simple. When one voice goes up, the other goes down. When one voice moves, the other voice stays put." What makes counterpoint difficult is that the vertical harmonies also have to line up (at all times!), which makes writing counterpoint similar to solving a Rubik's cube.
Below, I will use a piece called Concórdi Laetítia, which (unless I'm mistaken) is a very ancient text set to a "neo-Gregorian" (i.e. 19th century) melody. (Concórdi Laetítia from Pothier's 1903 Cantus Mariales) However, for our purposes, this piece will do just fine, because it's strophic (that is, the same melody repeats over and over). According to the Belgian school (which I follow), it is not at all artistic to use the same exact harmonization and registration over and over again for a strophic piece (like a Gregorian hymn). So, immediately, the challenge becomes: how many different ways can each verse be harmonized?
(VIDEO PRESENTATION, 1st verse) In the first verse, I don't do anything "fancy" (since it's the first verse), but I do sneak in a few walking bass lines (marked in purple).
(VIDEO PRESENTATION, 2nd verse) In the second verse, things begin to get more interesting, as I employ a walking bass line that goes from very low to very high, without a single skip. This method really helps accomplish all the goals we set earlier (chordal direction, chordal variety, etc.).
(VIDEO PRESENTATION, 3rd verse) In the third verse, I do the opposite; that is, I start up high and gently walk the bass line all the way down.
(VIDEO PRESENTATION, 4th verse) For the fourth verse, I still use walking bass lines, but my emphasis is more on variation in cadential chords. I also chose an interesting "fluty" organ registration (which one can get away with after multiple verses).
(VIDEO PRESENTATION, 5th verse) Finally, you pull out the "big guns" for the final repetition (colorful seventh chords, lots of motion in the voices, and even a "drive to the cadence"). As always, walking bass lines solve many of our problems (with regard to smooth voice leading, oblique motion, chordal direction, etc.).
And now, here's a video with all five verses in a row:
Those intrigued by this brief article are encouraged to "poke around" the St. Jean Lalande Library, or the other Corpus Christi Watershed Liturgical sites (which contain many hundreds of organ accompaniments). One especially good place to find "Belgian" accompaniments is our brand new, 180 page publication.