Mikro Usi Pressure Sphere 30

This is a pressure sphere designed to take a LOM Mikro Usi microphone. The sphere is 30mm in diameter and the ID of the hole through the sphere is 6.7mm. There are no depth stops inside the hole, so some means of securing the capsule inside the sphere is required. The 6.7mm diameter was derived from measurements but has not been tested against an actual microphone, so this is considered to be a best-effort. Some tweaking (e.g. drilling out with a slightly larger drill) may be required.