I do believe, however, that this is because I live in a fairly orthodox diocese.
Charles, my question is then, how much is too much when accompanying the singing
Charles: what you're seeing in the 'questions being brought up' is a wonderful demonstration that musicians CARE about distinguishing Lent from other seasons.
The GIRM says that the organ is not to be used except to accompany singing
In Lent the playing of the organ and musical instruments is allowed only in order to support the singing. Exceptions, however, are Laetare Sunday (Fourth Sunday of Lent), Solemnities, and Feasts.
The GIRM says nothing about registration. It just tells you not to play preludes, postludes, voluntaries, etc. at Mass.
the big 1700-pound bell really is noticeable
Actually many organists, myself included use an organ prelude on both Palm Sunday and Holy Thursday. A well thought, organ prelude enhances Palm Sunday's joyous beginning to the liturgy. Perhaps a chorale prelude on St. Theodulph. And during the blessing of palms, I use the setting of Hosana Filio David by Jean Demessiuex. Of course, as soon as the liturgy of the word begins, everything changes and I use the organ only to accompany singing. I don't use any more than my Swell Principal 8', Gedeckt 8', and my Spitz Flute 8' (Salicional like).
On Holy Thursday, I use an organ prelude as well. Actually I often use two - one on Ubi Caritas and one on Pange Lingua. There is a very gorgeous setting of Pange Lingua by Dupre from the 8 Short Gregorian Preludes collection. This year I'm just using one prelude - a set of variations on Ubi Caritas by Denis Bedard. And during the opening Hymn, Lift High the Cross, I nearly hit full organ, as well as during the Gloria. But then after the Gloria, I use only my swell 8's when necessary.
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