It’s the end of 2011 and Pentatonix has three things: money in the bank, a recently signed record deal and a hint of a fanbase after winning NBC's reality TV show the Sing Off. Not a bad situation to find yourself in. However, how do you go from there to placing yourself on the top of the charts?

Pentatonix' YouTube success has been incredible. Their Daft Punk medley, which is what won them the Grammy, has been viewed over 200 million times.

Pentatonix has eight other videos which have been viewed over 50 million times each, and you'd be hard pressed to find a video on their YouTube channel that hasn't gone viral.

After winning the Sing Off, Pentatonix went straight to the studio to record their debut album. To maintain their newfound following, they wanted to ‘keep it fresh’ and released covers of popular songs on YouTube. Although they had caught the industry’s attention, Kevin Olusola's quote (above) highlights the importance of having their own audience.

Penatonix – the a cappella group that managed to go mainstream. Their successes include a Grammy, a best selling album, the most subscribed to YouTube music channel that isn't on Vevo, multiple international sold out tours, and most recently – singing Jolene with Dolly herself.

In other words, Pentatonix is one of the first groups to use their online presence effectively to achieve 'traditional' success. So how did they do it?

Covering current popular songs makes you come up in common searches. This adds to the exposure and introduces you to a new audience. Pentatonix clearly knows this and has covered some of the biggest artists, including Ariana Grande, Beyoncé and Daft Punk.

Collaborations with other content creators (for example like they did with Lindsey Stirling) works as a cross promotion. It introduces Lindsey to Pentatonix' audience and vice versa.

When Pentatonix releases a video, they insure the best quality possible to them. If you go back to their first videos, they weren't posting videos with fancy production. They let their songs stand for themselves but ensured the best possible quality of the performance and the sound – fully utilising the potential of the YouTube's distribution opportunities.

They release videos regularly, so over the four year period their catalog has gained depth. Not to mention their album catalog now runs four full length albums and fourteen singles.

Their constant back and forth interaction with the audience is the most noticeable thing across every platform. No matter how successful they get, they always make sure to thank the fans – and very often leave a little message at the end of their videos.

That's not all, they also give personal updates on Instagram and thank the fans who came out to the shows on Twitter, and they've even released a full album commentary.

I’m just excited to be back on the road again and perform for our fans all over the world. They’re amazingly supportive and dedicated people. And so sweet!

– Mitch Grassi to Forbes in January 2015

The pairing of touring and social media creates a virtuous cycle where the live shows generate hype online. It goes something like this:

The Penatonix moved from tiny venues to 2000 capacity concert halls in their first 2-3 years of opeartion.