This is the eighth of a multi-part post. (Please see previous posts below for earlier installments.)
Example 9, Redford’s Dignare is from his Te Deum (30513, fol. 63r), in which all the organ versets are based ‘on the faburden’ of the plainsong, rather than on the plainsong notes themselves. In a basic ‘text-book’ faburden melody each phrase usually begins and ends on the same notes as in the plainsong, and otherwise the notes are usually put a 3rd up from the notated chant, although a unison with the chant may be used at any time. Faburden melodies are therefore variable, depending on what the performer/composer wishes, and sometimes even the notes at the beginning and ends of phrases are put up a 3rd. The example given by Morley (Introduction, Annotations ‘Upon the second Part’ for page 70; several copies are available at ISMLP) is of the plainsong Conditor alme siderum with ‘The faburden of this hymne’, in which the last note of each phrase (not the first) is the same as the chant; Morley also breaks the last few notes of the faburden into smaller note-values. Since Morley is describing the ‘old’ three-part improvised faburden, he comments that ‘And though this [the faburden] be prikt [i.e. notated] a third aboue the plainsong, yet was it alwaies sung vnder the plainsong’. Using this method, the faburdener would ‘sight’ in unison with, or a 3rd above, the notated plainsong and then ‘in voice’ transpose them all down an octave; alternatively the plainsong itself would be sung up an octave. Whichever way the transposition was done, the resulting sonority consisted primarily of parallel 6ths. Between these two parts another voice sang parallel 4ths against the plainsong.
When the faburden melody was to be used instead of the plainsong as the basis for improvised descant it was sometimes written out, making it easier to sight consonances from; see Lbl Harley MS 2945. Another method of making improvising on faburden easier is shown in a printed Sarum hymnal (Ruremond, 1528), in which the faburden is indicated by dots written above the plainsong (cf. Morley’s example).
Redford’s Dignare has a 1:1 descant below, and the top part has an ostinato point consisting of six repetitions of the rhythmic motif ‘dotted crotchet—quaver—crotchet’ (followed by a minim), which creates cross-rhythms against the plainsong minims. (On ‘points’ see Part 4.) Melodically this point consists of three repetitions of a six-note motif: a consonance, an upper neighbour, a return to the consonance; a repeat of the same consonance which then becomes a dissonance (a suspension) that is resolved with a ‘jumped resolution’ (i.e., a step up and then a leap down of a 3rd). Bathe gives examples of two suspensions (‘binding descant’), the second of which has a jumped resolution: 
William Bathe, True Art of Musicke,‘somtymes for the [part] of a not[e] a discord is vsed: commonly either binding, or with a prick [dotted note] as for example:
In Redford’s point these six notes are repeated twice, ending with a minim c’ (i.e. decorating the note c’); note the ‘barline’ placed after the point. The point then occurs on the note a, followed by another ‘barline’. For the third occurrence of the point it is shortened and altered to form the close; Morley, Introduction, p. 95, uses the term ‘dissolved’ for this procedure.
Example 9 Redford’s Dignare (Te Deum, GB-Lbl Add. MS 15233, fol. 6r):
 See Jane Flynn, ‘Tudor organ versets: echoes of an improvised tradition’, Journal of the Royal College of Organists n.s. 3 (2009), 5-23 (at 21-22).
 See Bathe, True Art of Musicke, ed. Karnes, p. 125.