As the Shure microphone product line expanded in the 1930s, Mr. Shure made certain that it was organized, and here is the “secret key”:

100 Series = microphones with carbon elements

200 Series = microphones with ceramic elements

300 Series = microphones with ribbon elements

400 Series = microphones with controlled magnetic/controlled reluctance elements

500 Series = microphones with dynamic elements

600 Series = not used as Electro-Voice had model numbers in the 600’s

700 Series = microphones with crystal elements

800 Series = microphones with condenser elements

Do the above still apply today?  Yes, to a certain extent they do.  Here are examples:

Model 104C has a carbon element.

Model 450 Series II originally had a controlled magnetic element; it was replaced with a dynamic element, but the model number was kept.

Model 545SD-LC has a dynamic element.

What about other current Shure microphone lines?

SM = Studio Microphone, not as in Shure Microphone

BETA = Beta, as in the product line that followed the “alpha” SM line

KSM = Kondenser Studio Microphone, as in “this sounds European”

MX = Microflex, as in small mics with flexible design to handle multiple applications

PG = Performance Gear

SV = Shure Vocal

VP = Video Production

WC = Wireless Countryman

WH = Wired Headset or Wireless Headset

WL = Wireless Lapel or Wireless Lavalier

So now you know the logic behind Shure microphone models numbers!  Thanks to Michael Pettersen, Shure’s Director of Applications Engineering for providing this information.