Hubbard returned to the USA in 1949 and founded a workshop with Dowd building harpsichords on historical principles, rather than the 20th-century modern (now known as 'revival') style practised by virtually all professional makers, such as
Robert Goble. Hubbard & Dowd found work performing restorations of harpsichords in public and private collections which helped them improve their own practises of design and construction. In 1958 the partnership ended and Hubbard formed his own workshop on the Lyman estate in
Waltham, Dowd opening a larger workshop in
Cambridge. From 1955–1958, with a
Fulbright Fellowship,
American Philosophical Society Grant and Belgium American Educational Foundation CRB Fellowship, he was able to examine many more instrumental collections in Europe. From 1967 to 1968, he set up the restoration workshop for the Musée Instrumental at the
Paris Conservatoire. In the 1970s, he taught courses at Harvard and
Boston University. At the time of the publication of his book,
Three Centuries of Harpsichord Making, in 1965, Ralph Kirkpatrick wrote that "he unquestionably knows more about the history and construction of harpsichords than anyone alive today". He developed a harpsichord in 1963 based on a
Pascal Taskin instrument of 1769 which was sold as a
do-it-yourself kit. It included a manual and all the crucial parts, with the wooden items planed to the correct thickness but otherwise requiring finishing. In this way any person with a good grasp of woodworking and basic knowledge of harpsichord making, with dedication and careful work, was able to produce a fine instrument. By 1975, approximately 1000 of these instruments had been produced. Some of Hubbard "kit harpsichords" have been (and still are now in the 21st century) used as first-rate instruments in public recitals worldwide. An amateur violinist, he also restored a number of
early violins to their original state and made early (pre-
Tourte) bows for instruments of the
viol and violin families. He has been described as "a
gentleman of the 18th and 20th centuries, an
Anglophile and
Francophile who seemed to disapprove of most things German and Italian." He died in 1976 in
Wellesley, Massachusetts. ==Hubbard's thoughts on the harpsichord==