In the twentieth century we have grown accustomed to the concept of the fixed ensemble. For example, if the words "string trio," were said to a relatively well-educated listener, that listener would be able to name the exact instruments belonging in the ensemble. This concept of fixed instrumentation allows composers to write for ensembles they know exist and for performers to establish certain types of ensembles with assurance that music exists for that mixture of instruments.
The expectations of pre-Baroque musicians and composers were very different than ours. For example, the concept of a fixed ensemble composed of specific instruments was relatively foreign. Egon Kenton reminds us that, "It must not be forgotten that there was no standard instrumental ensemble at that time, not even for a limited period." Kenton p. 491-2 It was not that there were no ideas or concepts of how music, even in its manifestation of wind ensembles, should be. This is true despite the claim that, "Instrumental style per se was not recognized or discussed by theorists in the fifteenth century, and even asinstrumental a repertory as dance accompaniment was not limited to instruments." MR p. 143There were indeed some theoretical and philosophical ideals, especially in the Middle Ages, that guided the nature and organization of instrumental ensembles.
The first relevant criterion was that of the pure consort. Instruments during the Middle Ages and the Early Renaissance tended to be designed and sold in families. A family would typically have several instruments of roughly the same design, but in different sizes and ranges. For example, the shawm family had seven members with ranging from the lowest, the bombarde, to the highest, a sopranino, with up to five instruments in between representing a wide selection of middle voices. The ideal was to have an ensemble containing only members of the same family. This was called an unmixed or pure consort. These pure consorts were especially popular in the early to middle fifteenth century, but gradually faded out of popularity during the course of the Renaissance.
Another theoretical concept during the Middle Ages regarded a separation between the 'loud' (haut) and the 'soft' (bas) instruments. The wind instruments of the pifarri--the shawms, trumpets, bombardes, and cornetts--would be considered loud. Among the instruments included in the soft category were lutes, vielles, rebecs, flutes, and even human voices. The ideal was that the two categories of instruments would never play together in an ensemble. This, too, is a more Medieval concept, and was decreasingly practiced ". . .though the medieval distinction between haut and bas--loud and soft--had largely broken down by then [mid to late sixteenth century]."Intermedii, p. 79
Please notice that I have specified that these are theoretical concepts, which were developed by theoretical musicians. In actual practice, they tended to be ignored or disregarded by the practical musicians who were actually in charge of creating and performing music. As Selfridge-Field says, ". . .there are two ways of approaching instrumental music. One was idealistically and intellectually, as the vocal composers and organists (i.e. the upper stratum of musicians) did, and as Zarlino recommended. The other was realistically and practically, as ensemble instrumentalists and other lesser mortals did." VIM For example, only one of the pifarri ensembles even came close to the ideal of the pure consort, the shawm and bombarde band. The other pifarri ensembles would not be considered pure consorts, however. Even the shawm and bombarde ensemble would periodically add a slide trumpet, which would 'ruin' that pure consort.
The actual practice of the loud/soft ideal was a little more common, especially as it makes a lot of musical sense. If a trumpet is playing with a harp, the harp will probably be drowned out by the louder brass instrument. Still, the concept was not always strictly adhered to by the "lesser mortals." Giovanni Gabrieli's cornett and trombone pifarri, which would typically be considered a loud ensemble, would frequently perform with voices, which were considered soft. As Crawford Young says ". . .strict, either-or classifications such as loud/soft have their place in Medieval theoretical writings, but in practice variety seems to have been the rule."CMRM, p. 143
Musicians, composers, and patrons of this period, despite having a set of theoretical ideals to worth with, did not pay much attention to the make-up of ensembles, and appeared to be rather uninterested in a fixed instrumentation or well-defined ensemble. H.M. Brown that, "Apparently, then, the concept of a wind band of trombones and cornetts was flexible enough to permit the addition of foreign elements." Brown, p. 61 Typically the additional instrument would be one in the middle range, like a crumhorn, recorder, or dolzaine. If further proof of the malleability of ensembles is required we need only look to Giovanni Gabrieli's groundbreaking work, Sonata Pian e Forte, which is scored for trombone, cornett and violin; two loud instruments and one soft one. It is not, however, only the cornett and trombone ensemble that was so flexible. The shawm and bombarde ensemble, as I mentioned earlier, could easily include a trumpet or an instrument in the middle range. The shawm and trombone ensemble could likewise easily have instruments added to it, whether they were more shawms and trombones, a vocalist to add text to the music of the instrumentalists, or simply another instrument that happened to be available.
The flexible nature of these ensembles makes it difficult for scholars to keep them well-defined, but it must have been a boon to their patrons. With this flexibility the pifarri could not only perform their usual duties, but could be combined to play for special gala events, in theater performances, for weddings, and generally be more fully in the life of their communities.