Physically shaping the pickup pattern

- [Instructor] If the mike capsule were simply placed … inside a solid mike body with the capsule at the end, … it would be omnidirectional. … However, almost all dynamic and mini condenser microphones … have slots or ports in the side of the mike body. … These ports let the sound from the back of the microphone … arrive at the back of the capsule … and they go around to the front of the capsule. … Because they follow those two paths, … they're out of phase at the mike capsule, … so the sounds from behind the mike diminish greatly. … So when you see ports on the side of a mike body, … they're there to shape the mike's polar pattern. … Covering those ports turns the cardioid microphone … into a omnidirectional mike. … Notice on this condenser mike that the cardioid version … has ports around the capsule, … but the omnidirectional version of the same mike is solid. … On this Shure SM58, as on the Shure SM57, … the lower part of the capsule has holes … all the way around. … And it's the same with the Blue Encore 200. …