Shure’s KSM8 Dualdyne microphone is the first handheld, dynamic vocal microphone to employ two diaphragms in the same capsule. The design uses a reverse airflow system that takes energy from the rear diaphragm, re-directs it, and alters its phase relationship with that of the front diaphragm to achieve control over proximity effect, frequency response, and directional characteristics. This enables the KSM8 to behave as an omni mic at low frequencies (enough to control the proximity effect) but maintain directionality to control bleed from nearby instruments.
The KSM8 has an internal pneumatic shock-mount that reduces handling noise, and a hardened carbon-steel grille lined with water-repellent fabric to protect the capsule from damage. Shure’s Diaphragm Stabilization System balances the active diaphragm when it is struck with plosive sounds.
The thing that makes the KSM8 innovative is that it provides the fidelity you would expect from a condenser mic, but with the ability to reduce leakage from nearby instruments, mitigate proximity effect and handling noise, and still have a wide enough sweet spot so you don’t have to stay glued to the grille when performing.