Thodoris Ziarkas is a double bassist, composer, and a teacher of the Alexander Technique from Greece. Growing up with the sounds of Greek folk music mainly focusing on local instruments such as the lyra and tsambouna, Thodoris evolved through different trajectories to discover the double bass, which led him to study jazz at Middlesex University in London, and film composition at Codarts Conservatoire in Rotterdam. 

His work as a composer focuses on contemporary composition which draws inspiration from Greek and Mediterranean traditions while simultaneously seeking new sonic landscapes. Using the double bass and the lyra as his main instruments, he explores soundscapes that emerge from silence, noise, and rhythmic patterns. His compositions incorporate elements of minimalism, electroacoustic techniques, and collage, combining field recordings to evoke the atmosphere of ritual traditions. 

Based in London since 2009 he is the co-founder of the psychedelic-jazz group Valia Calda which they co-lead together with his brother Nikos Ziarkas. Additionally he leads his own trio under the title of Collection of Sand and his recent work features the solo performance [Reconstruction] for double bass, electronics and film. Current collaborations include Nancy Mounir's Nozhet El Nofous (EG), Tom Sochas trio (UK), Oriol Mares & Talal Fayad Quartet (ES/NL), Vanessa Kourtesi (GR/NL), Ziad Rajab, and the duet with Tasos Stamou: AMAN!!!.

Over the last decade Thodoris has performed in numerous festivals all over Europe, the UK, USA, Cuba, Lebanon, and has appeared at the BBC, the Greek national television (ERT) and the TRT in Turkey.  As performer has collaborated with artists in the field of jazz, experimental and Mediterranean music such as: the London Improvisers Orchestra, Savina Yannatou, Yazz Ahmer, Chris Batchelor, Okay Temiz, Michalis Kouloumis, Alan Wilkinson, Toni Kofi, Anna Homler, Steve Beresford, Maggy Nichols, Beibei Wang, Adam Bohman, Sharon Gal, Electric Litany, Terry Day.

Combining his interest in improvisation, movement, and the Alexander Technique, Thodoris has collaborated with artists in the fields of dance and improvisation on the international scene. He has also composed music for film, theatre, and dance. 

From 2015 to 2020 Thodoris collaborated with dance artist and Alexander teacher Georgia Paizi on the improvisational practice project "the SEEd", mapping the common ground between movement and sound, through the principles of the Alexander technique. The SEEd's activities included lessons, seminars, and performances as well as printed materials and open discussions. The SEEd has traveled to London (Chisenhale Dance Space, Siobhan Davies), Berlin (TanzFabrik, DOCK11), Thessaloniki (AVGO), Syros (Akropoditi DanceFest), to the Music Village (Agios Lavrentios, Pelion), and to Aegina (Tsak Bam Festival).