DIY microphone kits & parts

We are now offering special pricing on our "SG" edition of Brian Fox' fantastic circuit mod for the Apex 460.

Included:

• Unbranded / unmarked Alctron HST11-A tube microphone (tested in the US)
• Fox SG circuit mod kit, with premium capacitors from Mial and Reliable
• EHX 6072 tube
• RK-12 capsule (or RK-47 available upon request)
• pure silver Kimber wire for the input circuit

As with all of our products, we give you everything you need, plus excellent DIY documentation, so you can spend more time recording music and less time shopping for parts.

The Fox mod kit creates an optimized CCDA circuit with very low noise and distortion. The circuit can be built with a C12-ish or Ela M 251-ish response; full instructions are included with the kit.

Learn more here.

Is your Studio Projects C1 or C3 too bright and hyped?

You shouldn't be surprised; it has the classic Chinese mic syndrome of a K67-type capsule and a (mostly) linear circuit.

While it is possible to change the capsule to a K47 type, we have a better solution: we've implemented the U87's high-frequency corrective EQ curve on a small add-on PCB that drops right into the Studio Projects C1 or C3:


Introductory price: $49

This is a DIY kit. Build it in about 15 minutes. It will take that 8-10kHz sizzle out of your mic, giving you a beautifully neutral midrange and top end, with just a hint of a lift in the highs.

The amount of high-frequency rolloff is adjustable, too, so you can dial in exactly as much as you want.

Click for more info on the "U87 EQ" mod kit for Studio Projects C1.

Click for more info on the "U87 EQ" mod kit for Studio Projects C3.

We have kits for both the older "797 Audio" cobranded mics, and the newer Studio Projects "Red Badge" mics. They're all subtly different. Each kit includes 100% of the needed components, and a full-color step-by-step instruction manual.

mparts said:

This is a DIY kit. Build it in about 15 minutes. It will take that 8-10kHz sizzle out of your mic, giving you a beautifully neutral midrange and top end, with just a hint of a lift in the highs.

The amount of high-frequency rolloff is adjustable, too, so you can dial in exactly as much as you want.

Click to expand...

Did this mod on my uncle's C1 that he hasn't used in years because of the excess sizzle... The mod was very easy, and in my quick test on vocals, it does perform very similarly to my poctop U87 clone (RK-87/cinemag transformer), which I used as a reference to dial in the high frequencies (I set the pot at 10 o' clock to match the high frequency response of the u87 clone). Seems like it should be a solid workhorse mic now... I'll report back once my uncle's had a chance to use it. Really impressed with the cost/performance ratio here. Might look for a used C1 or two for myself.

mparts said:

Is your Studio Projects C1 or C3 too bright and hyped?

You shouldn't be surprised; it has the classic Chinese mic syndrome of a K67-type capsule and a (mostly) linear circuit.

While it is possible to change the capsule to a K47 type, we have a better solution: we've implemented the U87's high-frequency corrective EQ curve on a small add-on PCB that drops right into the Studio Projects C1 or C3:

Introductory price: $49

This is a DIY kit. Build it in about 15 minutes. It will take that 8-10kHz sizzle out of your mic, giving you a beautifully neutral midrange and top end, with just a hint of a lift in the highs.

The amount of high-frequency rolloff is adjustable, too, so you can dial in exactly as much as you want.

Click for more info on the "U87 EQ" mod kit for Studio Projects C1.

Click for more info on the "U87 EQ" mod kit for Studio Projects C3.

We have kits for both the older "797 Audio" cobranded mics, and the newer Studio Projects "Red Badge" mics. They're all subtly different. Each kit includes 100% of the needed components, and a full-color step-by-step instruction manual.

Click to expand...

As soon as I got the email announcing the kit we purchased a 797 C1 on Ebay and upgraded it. Very pleased with the results.

We got tired of building fantastic-sounding modded microphones that still looked like this on the outside:



So, we made some fancy new headbaskets:



With a bit of spray enamel and a new grille, the 990 becomes a very attractive microphone:



See 3D prints of the design process, and more photos here:
Retrofit grille for MXL 990

The "Linear 87" kit was designed for us by Mark Fouxman (aka Marik) of Samar Audio. The circuit is a single-stage JFET/transformer based on the KM84/U87 model. We found a cache of NOS TI-brand 2N3819 JFETs, just like Neumann used to use. We select them for IDSS and headroom, and bias them individually here, so builders need not worry about turning trimpots and guesstimating bias based on voltage. We're using high-grade parts throughout the circuit, which is built on a custom PCB of our own design. We're using a custom Samar transformer. Specify your capsule choice at the time of ordering.  You would need to supply your own CAD GXL3000 (~$99) or Golden Age FC3; one or the other of these donor mics is required for this kit, as we need the body and the DC board as well.

The finished mic has better sensitivity than the U87Ai, and significantly better sensitivity than the U87i and DIY U87 clones. Noise performance is excellent. The mic's tone is excellent; customers tell us this has become their favorite vocal mic. Choose from our all-brass K47 replica, the RK-47, for a Fet47 sound profile, or the RK-12 for something that's maybe not as natural but maybe more lively and exciting.

Read more about the Linear 87.

Here's a photo of the audio circuit; you can see that there are only about 14 parts, nicely laid out.


The kit includes a full wiring upgrade, all US-made milspec silver/teflon stock, too.