FAQ

Q: My microphone is broken. If I install a new capsule, will that fix it?

A: We never recommend modifying a broken microphone. Unless you are sure that your broken mic's capsule is bad, and further that nothing else in the mic is bad, the risk is high that the mic will continue to not  work after a new capsule is installed.

Therefore, we recommend fixing the microphone first, before upgrading it.

There is one exception to the above advice: If you plan to replace both the circuit and capsule -- if, that is, you're using the broken mic just as a "donor body" -- then it makes great sense to start with a broken microphone.

Q: Do you have any mods for [insert obscure microphone here]?

A: First, see our directory of mic mods. If we have specific suggestions for your mic, they'll be listed in that collection.

If your mic is not listed in that collection, then we do not have specific suggestions for it.

In most cases, you could probably change the capsule. We provide two different mounts with each of our large-diaphragm capsules, but we cannot guarantee that our capsules are easily installed into arbitrary obscure microphones. If you have questions about compatibility, email us an in-focus photo of your microphone's existing capsule and mount.

In some cases, one of our circuit kits might fit. Find the PCB outline diagram on both the MP-V57 and T-84 product pages; click it to download a PDF that shows the board dimensions. Print that document, cut out the paper template, and hold it up to your donor mic's chassis. Does it fit? Do the mounting holes line up? If so, then that circuit will fit your mic.

Q: Do your capsules work in electret microphones?

A: Electret microphones require electret capsules, such as the TSB-2555.

Because electret microphones usually do not provide polarizing voltage to the capsule, our large-diaphragm models (RK-12, RK-47, RK-87) will not work there.

If you're not sure if your mic is an electret, research it at the RecordingHacks microphone database.

Q: Which of your DIY microphone kits is easiest to build?

A: In order of difficulty, from least to most, we rank our products as follows:

  1. Capsule installation. If you're new to DIY audio, the easiest and biggest bang-for-the-buck mod is to install an RK-47 into one of the inexpensive transformerless microphones listed in our mic mods directory. See the MCA SP1, MXL 910 (when on sale), MXL 990, etc.
  2. Studio Projects C1 EQ mod. (Also available for the C3.)
  3. S-25 DIY microphone kit. This is the easiest all-inclusive microphone kit we make.
  4. T-series microphone kit, or T-84 Circuit Kit.
  5. S-12, S-47, S-87 DIY microphone kit, or MP-V57 Circuit Kit.
  6. 12-251 tube microphone kit, or Fox 460 tube circuit kit.

In all cases, we strongly recommend that you learn how to solder first. Please do not risk expensive DIY audio components if you are not comfortable forming good solder joints.

 Q: Which of your kits is best for [male vocals | female vocals | rap vocals | acoustic guitar | etc ]?

A: See the Application Guide.

But please understand that these are guidelines only. Nearly any microphone can be used on nearly any source, depending on what sound you're going for.

Q: What are the differences between the transformerless circuit kit and the transformer-coupled circuit kit?

Sonic differences

The transformer circuit has much more second harmonic distortion (aka coloration) than the transformerless circuit, due both to the operation of the JFET and to the transformer. 2nd Harmonic distortion is, in many applications, a welcome characteristic. It gives grit, weight, and authority to a track. Note that most vintage microphones do impart such coloration to their tracks, because most vintage microphones used transformers, whose sonic imperfections are usually perceived as a benefit.

The transformerless circuit has higher output, and is more likely to need a pad on moderate-volume sources.

Feature differences

The transformer circuit (T-84) has two internal switches, one for pattern (Cardioid/Omni) and one for pad. Both can be used independently.

The MP-V57 transformerless circuit has one switch, which can be used either for pattern (Cardioid/Omni) or for pad, but not both.

The 990 transformerless circuit has one switch, designed to be used only for pattern (Cardioid/Omni).

The TL3 transformerless circuit has two external switches. One is a 3-way pattern switch (Omni/Cardioid/Fig8), and the other is a pad. Both can be used independently, without opening the microphone.

All the transformerless circuits (990, TL3, MP-V57, SDC) can optionally be built with high-frequency corrective EQ to roll off the highs from the capsule. In the case of the TL3, the EQ capacitor is socketed, facilitating experimentation and per-session tuning.

Build differences

The transformer circuit (T-84) is easier to build than any of the transformerless options. It has a lower parts count, and a lower count of polarized parts. (Polarized parts must be installed in a specific orientation, matching positive and negative legs for example.)

Cost Differences

The transformer circuit costs more than the single- and two-pattern transformerless circuits, because making great custom-wound transformers is expensive.

The TL3 circuit is priced slightly higher than the T-84 circuit because it required a significant amount of R&D, and because the finished TL3 will go head to head with any 3-pattern FET mic on the market.

Q: I broke a part in my kit. Can I get a replacement?

A: We have a flat fee for most replacement parts: $10 for domestic US orders, including USPS Priority postage, or $20 for international orders, including USPS 1st Class International postage. The flat fee does not cover tubes, transformers, capsules, or microphone body parts, but rather is intended for circuit components such as capacitors, diodes, inductors, resistors, etc.

Before requesting replacement parts, please inspect your kit to ensure that it is complete in every other respect.

Q: The T-84 / T-series circuit kit includes a 3pF capacitor, but I received a 5pF capacitor. Do I need to replace this part?


A: The label actually says "3 ± .5pF". In other words, this is a 3pF capacitor, with an actual value between 2.5–3.5pF. It is not a 5pF capacitor.