Dr Eastham came to Australia in 1994 and studied with distinguished violin teacher, Elizabeth Holowell. She gained a Bachelor of Music degree with Honours in performance and research (Mozart's Violin Concertos) in 1998 at the University of Newcastle, under the supervision of Prof. Robert Constable. She joined the staff of the University of Newcastle Conservatorium in 2000. Sohyun began a PhD programme in 2000 under the supervision of Assoc. Prof. Michael Ewans and Elizabeth Holowell. In 2007 she was awarded the degree of Doctor of Philosophy. The title of the thesis is "The Role of the Violin in Expressing the Musical Ideas of the Romantic Period and the Development of Violin Techniques in the 19th and Early 20th Centuries”. Five live recordings were produced to fulfil the creative part of her doctoral study. These included: the complete Brahms's violin sonatas, and various works from Schumann, Schubert, Prokofiev, Ravel, Saint-Saëns, Kreisler, Tchaikovsky, among others. Sohyun is the director of the chamber orchestra and has coordinated the string programme at Avondale College of Higher Education from 1999, and is still a violin lecturer there. She was a member of the Hunter Symphony Orchestra from 1997 to 2000. Currently Dr Eastham is teaching at the University of Newcastle - School of Drama, Fine Art and Music. Several of her students have gained AMusA and LMusA diplomas, and many others currently hold scholarships. In 2009 Dr Eastham published her first book The Violin and Romanticism. In this book she investigates the violin technique and styles used in the Romantic Period as well as the writings of over 20 treatises from writers of the period. Released in September 2011 is her violin album Gentle Whisper recorded with Psalter. Sohyun has recorded a second CD - Journey of the Spirit. This album has music composed by Colin Spiers and was released in August 2012. In 2015 she was an adjudicator for Wollongong eisteddfod.