Dallahan has his roots deeply rooted in Irish folk music, but brings much else into the band's music – Scottish music, Balkan tones, jazz, funk, pop and classical music. The result is a unique, brightly colored and almost seamless musical tapestry. It's a band that takes the audience on a musical journey from atmospheric Transylvanian songs to hard-hitting Irish dance music with funky rhythms - and everything in between.

The band consists of Irish-born singer and guitarist Jack Badcock, virtuoso Ciarán Ryan on banjo, mandolin and fiddle, the ever-smiling Andrew Waite on accordion and – as the newest member – winner of the BBC Radio Scotland Young Traditional Musician of the Year 2019, Benedict Morris , on the violin.

Dallahan's first album, When the Day is on the Turn, was released in August 2014. It was very well received by critics and audiences alike and was year after year nominated for best album at the MG Alba Scots Trad Music Awards. The track "The Tartar Frigate" was also named Instrumental Track of the Year at the LiveIreland Awards 2016. The band released their second album, Matter of Time, in April 2016 - an album that really encapsulated the distinctive sound and style that the band has developed since they started. The album was nominated for Album of the Year at the Scots Trad Music Awards the same year. In 2018, the band's third album, Smallworld, was released, which really demonstrated Jack Badcock's skills as a songwriter, and in June 2023, the band's latest album, Speak of the Devil, was released, with exclusively own compositions.