Shure Apps Tech Tip – Difference between the SM57 and the SM58
There is a plethora of pro audio myth regarding the SM57 and the SM58, and how they differ. But no matter what is posted on the Internet, the fundamental difference is the type of protective grille: the SM58 has a metal ball grille and the SM57 has a plastic cylindrical grille that rotates. The shape of each grille does slightly affect the high frequency response and this may seen on the frequency response graph printed on the User Guide supplied with each model.
Links to the Shure Technical FAQ on this topic:
The SM57 was introduced in 1965, and the SM58 in 1966. Both models employ the Unidyne III microphone element, developed by Shure engineer Ernie Seeler, and first used in the model 545 introduced in 1959. The 545SD is essentially an SM57 with an on/off switch. “SM” stands for Studio Microphone as the SM57 and SM58 were originally developed for use in television studios. Two features were very important for TV: 1) The non-reflective gray finish to prevent reflections of the TV studio lights, and 2) the lack of an on/off switch to prevent onscreen talent from accidentally muting the mic.