|Delta Sleep are a British math rock band, formed in 2010 in Canterbury, Kent. They are currently based in Brighton and consist of Devin Yüceil on guitar and vocals, Glen Hodgson on guitar, Dave Jackson on bass and Blake Mostyn on drums. They have so far released 4 EPs and 4 albums. Delta Sleep emerged from a band called Sávlön, featuring bass player Maria Sullivan and drummer Adam Brodigan beside Yüceil and Hodgson. They released a self-titled EP in 2010, followed by Management in 2013. Shortly after the release of Management, Sullivan and Brogan left the band to start a family and focus on other musical projects, respectively. They were replaced by Dave Jackson and Blake Mostyn, both friends of the band. Delta Sleep released their first full-length album Twin Galaxies in January 2015. Their second full-length album, Ghost City, was released in August 2018 to critical acclaim. Ghost City was promoted with tours in Europe, North America and East Asia. During touring for Ghost City, Delta Sleep released their EP Younger Years as a surprise in September 2019. Following cancelled tour dates due to the COVID-19 pandemic, Delta Sleep gradually released their compilation album Soft Sounds between May and July 2020. Soft Sounds consists of 9 stripped-down and acoustic live performances that were recorded during touring in France, Japan, the United States and Turkey as well as the new song "A Casa". In March 2021, Delta Sleep left Big Scary Monsters and started their own independent record label called Sofa Boy Records which is named after their song 'Sofa Boy' from The Younger Years EP. In June 2021, Delta Sleep released their new single "The Detail" and announced their third album Spring Island. Both Twin Galaxies and Ghost City are concept albums that follow a protagonist overcoming hardship. Twin Galaxies follows a man whose life was uprooted by a flood on his way to find new hope. In Ghost City, a woman escapes from a dystopian, oppressive city to find a better life more in connection with nature. In contrast, Younger Years was written without an overarching concept in mind. Delta Sleep's musical style has been described as math rock and indie rock. Many songs feature odd time signatures and are structured unconventionally.