The site, , will feature exclusive, free editorial content provided by the creators of gossip sites HolyMoly.co.uk and PopJustice.com, and will offer an extensive library of downloads, including music from unsigned bands.
It has been backed by a £2m spend, the biggest investment in channel4.com for more than five years.
Paul Whitehead, head of business development at Channel 4 New Media, said: "Our ambition is for the site to become one of the leading music destinations in the UK. Using our internal creative resources and those of our partner businesses we are going to bring a new level of humour, creativity and insight into the online music arena."
The site will contain gig listings and a library of downloadable songs featured on Channel 4 and E4 programmes, such as 'The OC', in the last two years.
The site will offer new bands the chance to build their own pages and make sample tracks available to listen to and vote for.
Editorial content will be produced by Peter Robinson, editor of , and Mr Holy Moly, editor of , which together won Channel 4's tender.
Robinson said: "The new site will be celebrating great music, regardless of genre. Although we're looking forward to featuring some astonishingly bad music, too, if the perpetrators are interesting enough."
Digital design agency Holler is responsible for the design of the site.
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