Taking after the bullet mics Shure introduced in 1949, which in and of themselves were evolutions from the first desk-mounted announcement microphones, the Shure 520DX is the most up-to-date iteration of the company's green bullet harmonica mic. Known for its distinctive "blues harp voice," the 520DX features an onboard volume knob that allows you to dial in on the fly, and its 1/4" plug gives you the opportunity to plug into any high-impedance device. Use it for your harmonica or if you're digging the lo-fi sound.