The AKG C414 has had many redesigns since the version was released in 1971. The “ULS” was made first available in the mid 1980’s and stands for “Ultra Linear Series” and has a redesigned circuit that lowers the noise floor. This era of 414, which uses a nylon capsule in place of the original CK12 found in the early 70’s versions, has a flat, somewhat bland characteristic. So why do we have four of them? Because they are incredibly flexible with multiple polar patterns, two-stage pre-attenuation pad, bass cut filter and high sound pressure level capability.