Si Hayden is an English musician and long time guitarist of 70's electric violin veteran Joe O'Donnell of East Of Eden, Headstone and Rory Gallagher fame. He has released over 60 albums of largely original material, featured on multiple guitar compilations with the likes of Alex De Grassi, Guns N' Roses guitarist Bumblefoot and Will Ackerman. He has recorded as a guest musician on over 100 releases. On the release of his 2011 solo guitar album Supercharger, Guitarist Magazine described him as 'an acoustic virtuoso'.
Hayden has performed and recorded with artists such as John Etheridge, Gilad Atzmon as guitarist in the 'Atzmob', Clive Carroll and Soweto Kinch. Other groups have included The Morley Hayden Haines trio who performed at The Guinness Cork Jazz Festival in 2009 and BBC1 television appearances with Rob Halligan. Si is also a founder member of 91db who released their debut album 'Waiting' in 2010, their next release was a remix that appeared on Rik Mayall's Noble England EP. The single from the EP reached number one in the Official UK Independent Charts in 2014.