Andrew Beck

According to Shure's artist page, Imagine Dragons uses Shure's SM57 for their guitar cabinet.

In this photo, Andrew can be seen next to Dan Reynolds, playing a maroon colored Ibanez Electric accoustic guitar for a house concert at the Reynolds' in Las Vegas. This show took place circa 2008 before the band rose to fame.

In this photo, as well as on their website in multiple places, Andrew can be seen playing a vintage Kay Vanguard.

This instagram photo show's Andrew's Gretsch.

Andrew is pictured here with the electric piano at an Imagine Dragons Concert at the Velour. He is sporting a fake, drawn-on moustache that became one of the calling cards that members and fans alike wore in the early days of the band.

In this photo and others on their site, you can see andrew playing a vintage Kay Vanguard.