The first prize winner at Georgia Tech Guthman Musical Instrument Competition in 2014 and People’s Choice Award winner in 2021, Tolgahan Çoğulu, designed his "Adjustable Microtonal Guitar" in 2008. He designed the “Lego Microtonal Guitar” in 2020 with his son Atlas Çoğulu and Ruşen Can Acet and “Automatic Microtonal Guitar” in 2021 with Selçuk Keser. His first CD with microtonal guitar, Atlas, was published by Kalan Music in 2012. His microtonal guitar has taken him to many festivals and universities in 36 countries including Singapore, USA, Mexico, China, Malaysia, Australia. Tolgahan is building a repertoire for microtonal guitar with more than 40 composers involved at this point. In 2019, he became a Professor in Guitar at Istanbul Technical University’s Turkish Music State Conservatory, where he had founded the classical guitar department in 2010 and the world’s first microtonal guitar department in 2014. He has been organizing the world's first “Microtonal Guitar Competition” since 2016. His solo album ‘Microtonal’ was released in 2018 and duo album with Sinan Ayyıldız “Amorphous” in 2021 by Ahenk Music. His latest concerts with Sinan Ayyıldız include WOMEX’21 Showcase in Porto, 71st Granada Festival, Tres Culturas Foundacion Sevilla, Leibnitz Jazz Festsival. Currently, he is teaching at Istanbul Technical University Turkish Music State Conservatory and Centre for Advanced Studies in Music.