Mic Mods

The common term for what I do is mic mods — but that’s not quite accurate. What I actually do are full rebuilds: I completely gut the mic and replace everything inside. Still, if I called them mic rebuilds, the search engine gods would leave me in the dust and you wouldn't be reading this right now. So, mic mods it is!

New Era: Laser Engraving

As of Sept 2025, RockScience mic builds will no longer have badges attached with epoxy or color paint options. Those store options are now retired in favor of Laser Engraved graphics.

Every mic now leaves the shop with:

A laser-engraved RockScience logo
An engraved build configuration code (so you always know exactly what’s inside—47TL, 47TC.C, etc.)

Nothing inside has changed. The capsules, transformers, and electronics—the guts that make these microphones special—are still built with the same love and detail as always.

This gets me out of the epoxy and badge-bending business and lets me focus on what really matters: building the best-sounding mics possible.

I rebuild low-cost large diaphragm condenser (LDC) and small diaphragm condenser (SDC) mics from brands like MXL, Sterling, M-Audio, and others. Custom imported bodies are also in the mix. I work with both transformerless (TL) and transformer-coupled (TC) circuits — with a particular passion for the character and sound of the transformers.

Want more of the story? Read on. 🎙️ Or skip all that and have a look around the store 🎙️

The Circuits

I build two flavors of microphone circuitry: Transformerless (TL) and Transformer-Coupled (TC). The original TL board is called the jaSb (just another Schoeps board). Like nearly every other low-cost TL mic, it's inspired by the elegant Schoeps CM5 circuit— adapted here for a large diaphragm capsule. It has very fast transient response and very low noise.

mxl mic mod — Stock MXL surface-mounted board (L) and the jaSb

Next came the Transformer Coupled circuitry. This is modeled after the Neuman KM-84 circuit again adapted for LDCs. I call it the BFM (Big F'n Microphone). These days, I am mostly doing TCs. I generally prefer the harmonic richness and simplicity of the circuit. Like the jaSb, the BFM features discrete high quality components, Point to Point capsule wiring and hand-selected biasing resistors. There have been many adaptations of the BFM for different mic bodies and some of them support external Pad and Filter switches (like for the MXL770/990s, MXL5000, Sterling ST55)

The Capsules

The two capsule types I mostly deal with are k47-style center-terminates and CK12-style edge-terminated. The k47 is a more mid-forward full tone, while the CK12 has a more extended and silky top-end. I will only put k47s in the TL mics but either works wonderfully in the TC builds.

mic mod caspsules — k47(L) and CK12 capsules

I designed custom capsule cradles that fit a variety of mic bodies and support both K47 and CK12-style capsules.

mic mods — Two variations of the capsule cradle

Build Configuration Codes

Every mic now has its configuration code engraved on the body. The format is:

47 TC . C
|  |    |
|  |    +-- (TC only) Transformer type: C = Cinemag, A = AMI, 3 = 3U, N = Neutrik(lo-fi)
|  +------- Circuit: TL = Transformerless, TC = Transformer-Coupled
+---------- Capsule: 47 = K47-style, 12 = CK12=style

Examples:

12TC.A = CK12-style capsule, transformer-coupled with AMI
47TL = K47-style capsule, transformerless
47TC.C = K47-style capsule, transformer-coupled with Cinemag

Some Family Snapshots

There is a lot of photography to redo now that the badges and colors have been retired.

Have a look in the shop window

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