A dearth of facts about many of the composers and musicians of the early Baroque period is common, but in the case of Dario Castello, there is nothing to acknowledge that such a man even existed, except for two books of Sonate concertate in stil moderno (“Concerted sonatas in modern style”) and a motet that appeared in the Ghirlanda sacra collection. The title pages of the instrumental collections name him as capo di compagnia de instrumenti (“head of the company of instruments”) in Venice, and as a musician at Saint Mark’s. The frequency with which his works were re–issued, notwithstanding their difficulty, demonstrates their popularity long after his presumed death in about 1630, due, as with so many others, to the outbreak of plague.
Many towns in Germany and northern Italy employed instrumental bands or piffari, comprising trumpets, sackbutts, cornetts and various other wind instruments. They played on ceremonial occasions and at other public settings like concerts. In Venice, there were several such bands, including one attached to the retinue of the Doge. Castello, it seems, was in charge of one or more of these, and thus probably played the cornett, sackbutt, dulcian (ancestor of the bassoon) or perhaps even all three.
His first book of twelve Sonate concertate for two and three voices was published in 1621 in Venice. The works are longer than those of Rossi, and conspicuously canzona–like, multi–sectioned works exhibiting various improvisational techniques, such as embellishment of chordal components reminiscent of contrapunto alla mente (a related instrumental technique known as sortisatio)
or sequential imitation.
Castello was among the earliest Baroque composers to indicate changes in tempo with descriptions such as alegra (“lively”), adasio (“slowly”) or presto (“hurry”), and to mark contrasting dynamics (volume) such as pian (“quiet”), pianino (“quieter”), forte (“strong,” i.e. loud) or ecco (“echo”) to make his intent clear. Similarly, some ornaments either are written out in full or are, like the trillo, marked explicitly.
Nevertheless, there are solo passages where only one instrument plays at a time (with continuo), succeeded by the same solo for another instrument, where each player has an opportunity to embellish ad libitum.A suspicion that Castello was a virtuoso not just of the cornett but perhaps the dulcian (bassoon) and trombone, even the violin, becomes more compelling when one turns to his second book of Sonate published in 1629. As in the preceding collection, he specifies only soprano or soprani for many of the works. There are long sustained notes over which rapid and dramatic figuration takes place
as well as slower lyrical passages in which articulation is marked deliberately.
And there are the electric segments of declamatory bravado that show off the unique capability of instruments.
Where he does name specific instruments, Castello understands their unique capacities and limitations, and exploits them where needed: slurs and tremolo are marked for dulcian (bassoon) just as for parts presumed to be for violins
and sackbutts (trombones) are expected to play rapid passages in spite of their more cumbersome method of producing changes of pitch.
It is especially prominent in the last three sonatas. The penultimate two are score explicitly for stromenti d’arco (“bowed instruments”), and the closing sonata is in ecco per doi cornetti e due violini (“in echo for two cornetts and two violins”), a notably enjoyable work for what perhaps were his two favourite instruments, with delightful echo passages.