Although one might think of the curved bow as, somehow, emblematic of string playing, the fascinating world of polyphonic performance and evidence from former times are still open to investigation.
The practice of polyphonic playing using such kinds of bows is documented by the Renaissance era lira da braccio virtuoso Alessandro Striggio (1540-
The BACH.Bow is especially conceived for polyphonic playing and its research and development phase has been both lengthy and intensive. A variety of disciplines has been called upon: mathematics and geometry, studies of materials, design, building of prototypes, development of playing techniques, composition, recordings and concerts. This whole cycle was repeated several times before a definitive design was arrived at. The new design takes into account the particulars of both human anatomy and the geometry of string instruments.
Ever since the publication in 1905 of Albert Schweitzer's ground-
Certain musicologists (David Boyden, for example) have questioned the use of the curved bow, but their notions seem to be based more on theory than actual use of the bow itself. Two texts, on the other hand, clearly document use of the curved bow: Rudolf Gaehler’s book Der Rundbogen für Violine -
Rudolf Gaehler summarizes all important texts on the curved bow which have been published in the 20th century. His primary concern is to show the feasibility of Bach’s polyphonic notation and its execution with the curved bow. His CD realease of all six Sonatas and Partitas confirms very convincingly both this thesis and his own mastery of polyphonic playing.
Michael Bach proposes a new interpretative approach to the Suites and focuses on the exceptional variety of sound production afforded by the curved bow. He reveals a farsighted and broad view of interpretation with the curved bow; in particular, the interpreter’s free choice of playing the notated material as chords or as arpeggios. Even the arpeggios can be played with unparalleled variety, far greater than anything imaginable with the conventional concave bow. It is even possible to add successive voices without dropping the preceeding ones. In addition, the tension of the hairs on the curved bow can be controlled flexibly and precisely, permitting heretofore unknown sound qualities on one or more strings in both monophonic and polyphonic textures.