R&A will also host Wax Mustang, Reb Fountain, Racing Truth, Trei Fairbrother Ferby and K2K There's A Tuesday.
2020 marks Rhythm & Alps' 10-year anniversary as the premier summer festival of the South Island.
"We've carefully hand-picked these acts from around Aotearoa to highlight the diverse talent that New Zealand has to offer," said Rhythm & Alps festival director Alex Turnbull.
"This is a one-off quintessential Kiwi all-star festival, with a second announcement still to come!"
