SCORING THE BRASS AS AN INDEPENDENT SECTION
Scoring the brass instruments as an independent section takes divergent paths from those previously considered for the strings and woodwinds. The dissimilar approach is due partly to the heterogeneous character of the brass section and partly to the limited scope of the idiomatic playing potentials of each instrument. In addition, the divisions within the section form homogeneous tonal clusters of horns, trumpets, and trombones with tuba. Their separate and combined ranges and tonal strengths determine voice distribution, fillers, and doublings. The whole conception of scoring for the brass section is so radically different from that of the other sections that it necessitates a totally changed set of values, perceptions, and objectives.
The scoring of chorals for the brass in varying numbers provides excellent experience in appraising the many problems occasioned by differing strengths and ranges. Practically identical compasses for horns and trombones, spanning the treble and bass registers, account for some unavoidable overlapping and doubling of parts. This normal playing range is similar to that of a male chorus. The trumpet's total range corresponds to that of a women's chorus solely in the treble clef. The full brass section therefore spans the tonal spread of a mixed chorus which, in turn, necessitates some doubling of inside parts.
The soprano, alto, and tenor parts can, with proper transpositions, be transcribed literally for three trumpets. Part writing will differ somewhat for adaptations for two trumpets (Example B-31).
For example, we find this type of writing in the opening of Lincolnshire Posy by Percy Grainger
Writing for trombones and tuba would require transposition to the range of a low voice choir (TTBB)
A second setting with open-position chords has some advantages. Melodies placed in inside parts tend to be unclear unless there is a minimum of movement in the other parts.
Scoring chorals for a quartet of mixed brasses (trumpets and horns) necessitates some rearrangement of parts due to unequal tonal strengths, as noted in Figure B-5b. Occasional overlapping of the alto and tenor parts is both inevitable and desirable in establishing good voice leading for the tonally stronger trumpets. The weaker horns can be adjusted to fit these voice patterns.
The addition of a trombone to the trumpet-horn quartet alters primarily the voice lines of the horns. With this grouping, it is desirable to have the two trumpets and trombone sound well together as a threepart unit and to readjust the inside harmony parts accordingly. With a low-melody tessitura some unison doublings will occur, while higher melodic lines allow better spacings.
Scoring America for a full brass section places each division in the ranges normally used for full orchestra: (1) The four horns take over the inverted chords, as given in Example I-27d. (2) The three trumpets remain unchanged (Example B-29). (3) The first and second trombones have harmony parts which will sound well with the trumpets and the bass octaves in the third trombone and tuba. The single melodic line in the first trumpet has sufficient tonal strength to carry the part adequately with the other supporting harmony instruments.
