With early bird tickets already sold out, Mountain Sounds Festival 2015 is shaping up to be the ultimate end-of-summer event.

But for those who can’t wait that long, the crew behind Mountain Sounds are throwing an epic launch party later this month. December 19 sees Sydney’s Oxford Art Factory taken over by the Mountain Sounds crew, where the likes of East, Olympic Ayres, Hockey Dad and I Know Leopard will show off their goods.

The festivities begin with Wollongong two-piece Hockey Dad and their mellowed brand of surf-rock, which caught the attention of Big Scary’s Tom Iansek, who recorded and produced their debut EP.

‘70s-inspired Sydney-siders I Know Leopard are up next, bringing their celestial pop tunes to the Oxford St stage.

FBi Radio SMAC Award nominee and Triple J favourite East follows on with her full live band and charismatic charm.

Closing the show on a dance-heavy note is the genre-smashing Olympic Ayres, who have been kicking up a serious storm with their infectious, disco-infused electronica.

Guests will be treated to a few sweet surprises and live art installations. Tickets are $14 pre-sale and $20 on the door