Microphone Parts: Capsules, Mod Kits, and More

High-grade microphone capsule upgrades, modification kits, output transformers and shockmounts:

Microphone Capsules: K47, K67, K87, CK-12

We believe microphones are essentially EQ devices. We further believe that if all your microphones sound the same, then your gear isn’t serving you as well as it could. We can help you build some extraordinarily musical variety into your mic locker.

We offer two versions of the K47 design pioneered by Neumann: the RK-47, a modern recreation of the capsule used in the Neumann U47, and the RK7, a hybrid of the M7 and K47 styles. Both offer classic “mid-forward” presence, and a wonderful contrast to the over-bright condensers that have overtaken the market.

We have an AKG CK-12 style capsule called the RK-12; it recreates the brightness and intimacy of the AKG C12 and Ela M 251 microphones.

And we offer two versions of Neumann’s venerable K67: the RK-87 is our go-to K67 capsule, made with 3-micron diaphragms and insulated backplates. The K67LE, an all-brass, limited-edition capsule that is a sort of sonic hybrid of the K47 and K67 designs.

Read more about all of our microphone capsules.

Mic Mod Kits

MXL 990 Mod Kit

Our circuit replacement kits let you turn inexpensive microphones into professional-grade studio workhorses.

We have kits for the Apex 460 (tube) and numerous FET mics: Studio Projects C1 and C3, most MXL, and popular mics from CAD, Nady, t.bone, and Golden Age. These are low-cost microphones with “good bones.” By replacing the circuit and capsule with our custom parts, we’re able to make these cheap mics compete with the high-dollar pedigreed mics you’d normally reach for first.

Read more about our mic mod kits.

DIY Microphone Kits

RA-23 Microphone Kit

We now offer all-inclusive DIY microphone kits: custom PCBs, custom metalwork, precision components, and a variety of capsule choices.

Introducing the MP-47


We stock a limited supply of hand-built, boutique microphones, such as our new MP-47. This mic uses our extraordinary transformerless circuit and our all-brass RK-47 capsule, to deliver vintage tone with modern performance specifications.

HOWTO / Tutorials

We have created several photo tutorials on large-diaphragm condenser microphone capsule replacement. The “microphone capsule swap 101” page shows step-by-step instructions for installing one of our large-diaphragm capsules. See also our listing of microphone capsule installation resources.


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