Johann Joachim Quantz describes in his Flötenschule (1752) two types of violoncelli in use: a huge one for use in an orchestra and a small, more comfortable for the masterly solo play and chamber music with a smaller arrangement. The standardisation of the instrument measurements and types in the 19^th century led to the fact that most continuo instruments were cut down to a standard size; the destiny of the instruments which were “too small” was that they had to be enlarged in an expensive way, or demotion to a child’s instrument or exclusive use by the tender hands of the alleged weaker gender. Hayer’s instrument is an archetypal "solocello" as Quantz would have liked it and compares in its present state to a violoncello which was used at the beginning of the 18^th century. 

Violoncello by Andre Castagneri, Paris 1736

Andre Castangneri was the first Italian violin builder who worked in Paris based on the traditions of his home country and who became famous. N. Harnoncourt owns and also played a violoncello by Castangneri.

Bow by J. Dodd, London End of the 18^th century

Bow by Arno Jochem della Rose (*1955)