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 three versions of Neumann’s venerable K67: the RK-67, a faithful 6-micron copy of the original; the RK-87, a 3-micron version of Neumann’s K87 (with insulated backplates); and 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 new “mod kits” let you turn inexpensive microphones into studio workhorses. We have a basic kit for beginners, so you can get into your first circuit upgrade for less than $50. And we have kits that require a bit more experience, but deliver a fully rebuilt and optimized circuit — something that will go head-to-head with the best condensers in your mic locker.

We have circuit upgrade kits for the Apex 460 and Alctron T-11 tube mics, and numerous FET mics: Studio Projects C1, MXL 990, 990S, 770, V63M, 2006, V250, MCA SP1, CAD GXL 2200 and GXL2400, Nady SCM-800 and SCM-900, Monoprice 60800, t.bone SC400. These are low-cost microphones with “good bones” — reasonably well-designed circuits that are somewhat crippled by the reality of meeting a low retail price point. By rewiring a critical portion of the circuit, and upgrading key components with audiophile-grade parts, we’re able to make these inexpensive mics compete with the high-dollar pedigreed mics you 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.

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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