This year's Tennent's Lager-sponsored T in the Park at its new home in Auchterarder will mark 20 years of the festival's grass roots music initiative that includes unsigned bands on the festival bill.

T Break started in 1996 and each year a panel of music industry experts listen to demo recordings submitted by ambitious artists and select those who will play the T Break Stage.

This year 16 unsigned acts will have the opportunity to be heard in front of the festival crowd at Strathallan Castle. Previous winners of the accolade include Biffy Clyro, Paolo Nutini, The View, Twin Atlantic and Snow Patrol.

Twin Atlantic's manager Aimmi Dunsmuir and Hector Bizerk frontman Louie join stalwarts including broadcaster and Sunday Herald columnist Vic Galloway and Herald and Times Group Arts Editor Alan Morrison on this year's selection panel.

Louie, a previous T Break artist himself, said: "I'm quite humbled to be invited to offer my opinions on T break's next wave of emerging talent. I have first-hand experience of the buzz that artists get from playing the T Break Stage and I'm really looking forward to sharing that moment with 16 new bands."

Acts should submit their best three tracks via Soundcloud through the T Break website (www.tennents.com/tbreak) or Facebook page (www.facebook.com/tennentstbreak). Full details on how to submit demos is available on both sites. T Break is open to musicians of all genres but to be involved entrants must be 18 or over, live in Scotland, and must be currently unsigned. Entries must be submitted before a deadline of midnight on Monday, April 6 2015. Judging will take place during May with the winners announced at the end of that month. The festival is July 10 - 12 this year.

Tennent's head of sponsorship George Kyle said: "Seeing so many Scottish unsigned musicians come through the process, and in some cases go on to achieve massive success, has been the source of much pride for Tennent's Lager as a brand and we look forward once again to all the entries coming in again this year."

DF Concerts promoter Dave McGeachan, also a member of the judging panel, added: "T Break has been an incredible 20 year journey. The great thing about T Break is it's so different every year, music styles change and fashion changes but the freshness and authenticity of Scotland's unsigned acts remains the same, I can't wait to hear what this year's acts have got to offer."