Susi Jeans (1911–1993), otherwise Lady Jeans, was an Austrian-born organist, musicologist and noted teacher. Born in Vienna, she was the oldest child of Oscar and Jektaterina Hock. Initially, she trained as a ballet dancer by the modernist teacher Gertrud Bodenwieser, but growing rather rapidly, switched to the piano. From 1925 to 1931, she studied piano at the Vienna Conservatory, with organ as a second study. This became her first instrument from about 1928, when she began studies with the composer Franz Schmidt and the organist Franz Schütz. In 1931, she was heard by the organist and composer Charles-Marie Widor. After criticising her pedal technique, which he thought not legato enough, Widor invited her to become a student. Although she accepted his offer, Jeans was always reluctant to discuss their lessons other than to say that he was a very old man at the time.Between 1933 and 1935, she studied at the Leipzig Kirchenmusikalisches Institut, Leipzig, with Karl Straube. It was whilst studying at Leipzig, however, that Jeans became aware of period instruments, which altered her musical interests considerably.Her first concert tour in Britain, in 1934, was a great success and the following year she returned to play at the Handel Festival in Cambridge. During this tour she met the astronomer and mathematician Sir James Hopwood Jeans OM, whom she married, in Vienna, in September 1935. They lived together at Cleveland Lodge, Westhumble in Surrey and gave issue to three children before Jeans' death in 1946. Before their marriage, Cleveland Lodge boasted a large three manual Willis II instrument in a specially built concert hall. In 1937, however, it was supplemented by a new tracker action instrument, built into her study by Eule of Bautzen. Although she later claimed that the action was installed by Hill, Norman and Beard, it was, nevertheless, the first neo-Classical instrument built in Britain in the 20th century.Advocating, amongst other theories, that Bach's trio sonatas were conceived with the pedal harpsichord in mind, rather than the organ, Jeans took delivery of a two manual and pedal harpsichord by Maendler-Schramm of Munich. In ensuing years, she was to make many broadcasts from this instrument and the study organ. With Sir James Jeans' death, Susi Jeans continued to live at the house until she died in 1993. She founded the Mickleham and Westhumble Festival in 1954, which was renamed the Boxhill Music Festival in 1966 and subsequently held at Cleveland Lodge almost until her death. She also founded and ran an annual summer school for organists.Susi Jeans' concert tours took her throughout Europe, the United States and Western Australia. She adjudicated major international competitions and from 1967 held a post at the University of Colorado. She is regarded as an important early champion of historically-informed performance and of historically-aware restorations of old instruments. Jeans championed many modern Germanic composers, not least her teacher Schmidt, and played a number of works that were dedicated to her by such composers as Augustinus Franz Kropfreiter (Toccata Francese) and Hendrik Andriessen (Thema met Variaties, written at Cleveland Lodge). Jeans was also an exponent of the clavichord, which she preferred to play above all other keyboard instruments. She performed both early and contemporary works on her favourite clavichord, a single-strung instrument by Thomas Goff clavichord, and maintained that clavichord technique was the backbone of all keyboard playing, whether this be organ, piano or harpsichord.Her scholarly interests ranged widely from organs, harpsichords and keyboard music, British music especially of the seventeenth and eighteenth centuries, Austrian music, to topics as diverse as William Herschel, mountaineering (she climbed the Matterhorn twice) and natural medicine. (Of the latter, most past pupils remember with glee the prescriptions of vitamin pills that she insisted they take, especially Vitamin B12 for co-ordination and Vitamin D for nerves.) She published many articles in scholarly journals, as well as editions of music. Her pupils included a wide range of musicians: George Guest, Peter Hurford, David Lumsden, Ralph Cupper, Tim Rishton, David Sanger and others. Others on whom she had a direct influence included harpsichordists Ruth Dyson and Davitt Moroney and, as a clavichord and harpsichordist, Jon Baxendale.Jeans bequeathed her house to the Royal School of Church Music in order that it could remain a centre for musicians. When the Royal School of Church Music relocated to Sarum College in Salisbury the Cleveland Lodge buildings, much restored and modified using lottery money, were sold to property developers who have carried out controversial demolition and building work, some of it without planning permission.