34mm Microphone Capsule Mount

thingiverse

This is a combination saddle and post for mounting a 34mm single or dual-backplate K87-style capsule in a generic Chinese microphone body (BM-700 / BM-800) for side-address use. The mounting holes are designed to match the holes found on any of the BM-700 and BM-800 derivative microphones. However, some of these microphones only have two tapped holes in their upper plates. The holes are specifically tapped to take M2.5 screws, making it possible to work with just two screws. If you decide to fully populate the mounting screws, be aware that you may need to purchase a tap and tap handle to finish the job. The mounting holes are designed to accommodate shock isolating grommets used for RC servos. Du-Bro #115 "Natural Rubber Grommets for Small Servos" or equivalent work perfectly fine. The stock screws that come with the donor mic may be too short to use with this mount due to the additional thickness of the grommets. I used M2.5x6mm screws with M2.5 washers to mount mine, which is the shortest screw I would consider using. There are two versions of the mount included: one for a single diaphragm capsule and another for a dual-diaphragm capsule. In both cases, the wires run down through holes that lead through the middle of the post and into the lower cavity of the mic body. For the single diaphragm model, wires enter only from one side, while the dual-diaphragm model has entry points on both sides of the capsule. The tunnel is 3mm in diameter, providing a tight fit for wires. However, you shouldn't need more than 3mm to get the job done. Neumann uses the equivalent of 30ga wire on their mics, and I used 28ga with room to spare. The thinner and floppier the wire, the less microphonic coupling you'll experience through the capsule wires. Unlike the saddle/post designs made for Transound capsules, this one includes four slots in the saddle so the capsule can be attached using screws. Most 34mm LDC capsules are threaded to take M1.6 screws. For single backplate capsules, use only one set of slots. For dual backplate capsules, the slots should be wide enough to engage the threaded holes of your choice in the capsule. Alternatively, you can attach the capsule to the saddle using an adhesive like E6000, just like the Transound designs. Unfortunately, this design includes steeper overhangs than the Transound designs, requiring you to print with supports.