Concerto grosso
Baroque concerto with solo and tutti groups.
What it means
The concerto grosso is a concerto form of the Baroque in which a small solo group, the concertino, stands opposite the full string orchestra with continuo. The usual solo group consists of two violins and bass, but there are many variants of scoring. The movements are usually arranged in a sequence of three or four pieces, often with changing tempi. Characteristic is that the soloists play along in the tutti and stand out only at the solo passages.
Musical use
The appeal lies in the alternation of density of sound. Recurring tutti sections, the ritornellos, frame the more agile solo sections and give the movement its order; the ritornello wanders through different keys and returns at the end to the original key. This layout shapes the concerto form of the eighteenth century as a whole. From the concerto grosso the solo concerto develops, in which a single instrument takes on the role of the concertino; for a time both forms exist side by side. In the twentieth century, composers deliberately take up the genre again.
Performance practice
Settle scoring and placement: the solo group should be audible but not set apart, and the ripieno must not become too large, otherwise the alternation is lost. Shape the transitions between tutti and solo in volume and articulation without changing the tempo. Work out the ritornellos as returns and note in which key they stand. In the continuo, the scoring adapts to the section. Practise the seams separately, because most uncertainties arise there.
Bear in mind that the order of movements is not uniform: some works follow the church sonata with changing tempi, others string together dance movements, still others approach the three-movement concerto. First get clarity about the layout. Watch the bass line, because it carries form and harmony and must not disappear in the tutti. Practise the ritornellos with the same articulation so that they are recognizable as returns. Settle size of forces and pitch before rehearsal work begins.
Also check whether the edition has added ornaments, and decide deliberately about their execution.