Jaroslav Sonsky was born in Lomnice nad Popelkou. 5 years old he went - from his own inner conviction - all by himself  secretly to apply for lessons with the piano teacher Bohumila Bendová (from the famous Benda family). She was surprised but received him in as her pupil. From the age of seven he learnt violin playing with Prof. Jaroslav Krása. After studies at the Prague Conservatory with Prof. Bretislav Ludvík he continued studying with Prof. Alexandr Plocek at HAMU (Prague Music Academy).  Especially from J. Krása and A. Plocek he got strong influences not only professionally but also in the human sense.  He kept contact with them both until their deaths. After finishing HAMU Jaroslav Sonsky continued private studies in chamber music with the legendary Prof. Ladislav Cerny.
During his military service he was active as soloist in the Army Artistic Ensemble. The years 1969-70 he worked in the Czech Philharmonic and later in the Czech Radio Orchestra. In 1975 he decided to emigrate to Sweden.
Jaroslav Sonsky took part in master courses several times with Prof. Semyon Snitkovsky, Tibor Varga, Nathan Milstein etc. In Sweden he developed his concert activity and also worked pedagogically. He started and led several chamber ensembles and with them he worked continuously and gave concerts. In 1978 he formed the piano trio EPOS TRIO (Anders Peterson – piano, Jaroslav Sonsky – violin, Ingemar Ohlsson – violoncello) and with the trio he took part in master courses with pianist Hans Leygraf, violoncellist Amadeo Baldovino (Trio di Trieste) and violinist Norbert Brainin (Amadeus Quartet).
In the eighties he received several times invitations together with the EPOS TRIO from Prof. Menahem Pressler (Beaux Arts Trio) to come to the Banff Centre in Canada and take part in master courses. Later on he teached as a violin Prof. himself in Canada at the Brandon University. From the year 1991 he was giving concerts with the new formed piano trio under the name variation EPOS TRIO-BERLIN (Gesine Tiefuhr – piano, Jaroslav Sonsky – violin, Jan Diesselhorst – violoncello). At the same time Jaroslav Sonsky performed duo concerts with

Leonora Josiovich pianist of the late Prof. Semyon Snitkovsky. 2001-09 he was working together with the well-known Brazilian pianist Patricia Bretas. During this time he performed many times in Brazil and the duo also gave concerts in several European countries including the Czech Republic.
As soloist Jaroslav Sonsky performed with many conductors for example Vladimir Valek, Leos Svárovský, Stanislav Vavrinek, Petr Louzenský. Also to be mentioned Gerard Oskamp, Jorma Panula, Ilarion Ionescu-Galati, Vojciech Rajsky etc. Apart from teaching in Canada he also gave master courses in the USA, Brazil and in a number of European countries.
Since 2008 Jaroslav Sonsky is developing chamber music cooperation with the outstanding French pianist
Sylvaine Wiart. After the all too early deceased violoncellist of EPOS TRIO-BERLIN Jan Diesselhorst he is performing with Gesine Tiefuhr doing a  virtuous and demanding repertoire for violin and harpsichord. In 2012he founded the string ensemble Martinů Strings Prague consisting of 12 members carrying on the Czech tradition of string culture.
As a soloist and with chamber productions Jaroslav Sonsky visited until now 24 countries. He made recordings for several well-known radio stations, gave concerts at very prestigious occasions, for instance  at the last official foreign visit to Germany by the late President of the Czech Republic Vaclav Havel or at the occasion before the historically first visit to the Czech Republic by the Swedish king.
His ideals are as well in his compound of repertoire as in the artistic aims of Josef Suk, David Oistrach and Henryk Szeryng.
He plays on a violin made by the French master Jean Baptista Vuillaume.
Further activities as manager etc.
For the Swedish symphony orchestra in Norrköping (SON) where he was a member he worked as a tour manager. Among his productions he managed a tour in the year 2000 to the Czech Republic, to Austria and Hungary and in 2009 to the Czech Republic and the Slovak Republic ; this was during the Swedish EU presidency.
Jaroslav Sonsky was member of the board for the international Bohuslav Martinu society. In Sweden he took initiative to, organized and fulfilled  in cooperation with the Embassy of the Czech Republic and the Czech Centre a series of cultural projects making propaganda for the Czech Republic.  Many Czech musicians were given the opportunity to perform in Sweden thanks to his invitations. In 2003 he  was awarded the prize of Jan Masaryk  - Gratias Agit (given by the Ministry for Foreign Affairs in the Czech Republic) for his long-time promotion of Czech culture abroad. In 2009 Jaroslav Sonsky appeared as one of the personalities in the documentary film: From Czech roots in Sweden.
He lives in Norrköping, Sweden and is recently also back in Prague.