V-251 Tube Microphone Kit
The V-251 Microphone is a recreation of the most famous female vocal microphone in history, the Telefunken ElaM 251.
We have implemented it with the best parts on the market: US-made, film-and-foil input and output capacitors, a selected low-noise 6072 tube from Russia, and a custom-wound T-14 transformer. The result is a stunning single-triode tube mic that rivals the performance of multi-thousand dollar commercial microphones.
The V-251 includes features not found in the original mic: switchable pad, switchable high-pass filter, and 9-way polar pattern control.
What's in the kit?
We provide everything you'll need to build a modern recreation of the Telefunken ElaM 251:
Complete metalwork. We provide the mic body, chassis, and grille. The brass body has a matte black finish. Switch markings are engraved for durability.
- Custom circuit boards. We designed these in-house and manufacture them in the US with DIY in mind. We use high quality two-layer boards with clear silkscreen markings and reasonably sized solder pads.
- Fantastic components. The kit includes 100% of components needed to build the mic circuit. All these parts are selected from among the best available, including low-noise Dale metal film resistors, a polystyrene input cap from Reliable, a polypropylene film and foil output cap from Reliable, high-grade electrolytics from Panasonic and Elna, a NOS styrene tone capacitor, Wima film capacitors, and a US-made T/14 output transformer.
- RK-12 capsule. This capsule is our version of the AKG CK-12. It is an edge-terminated capsule with dual diaphragms. It supports multipattern operation.
- Low-noise tube. The tube is a 6072a type, manufactured in Russia, then tested and selected in the US to conform to our specifications for noise and microphonics. We picked this 6072 over many other types because it has better distortion characteristics.
- Internal wiring. We've sourced pre-cut and tinned, color-coded, multistrand silver-plated OFC with Teflon insulation, made in the US specifically for this kit.
- Two HPF choices. We include two different capacitor values for the high-pass filter, so that you can choose at build time whether to build a "rumble" filter or a more traditional high-pass.
- Socketed HF EQ. Set the circuit's high-frequency rolloff via a socketed capacitor -- no soldering required for final tuning!
- Complete PSU with voltage mod parts. The V-251 kit includes a tested and functional power supply, plus a pair of diodes to be installed by the customer to adjust the supply's output voltage. (Alternatively, upgrade to our custom VPS1 PSU circuit.) We include an IEC power cord for US wall outlets.
- Unparalleled documentation. Each kit comes with a full color, step-by-step instruction manual. Our installation guides are known throughout the DIY audio community, and have been widely praised as the best available.
- Accessories. The V-251 kit includes an elastic shockmount (with spare elastics) and an aluminum flight case.
The kit does not include a soldering iron or other necessary tools; see our DIY audio tools listing for specific recommendations.
Not ready for DIY?
We're happy to build one of these for you; see the options here.
No premium-grade tube mic should be stuck using a cheap XLR cable -- which can cause up to a half-volt in loss to the critical tube heater supply. Upgrade to our Gotham GAC-7, custom terminated in the USA with authentic Gotham connectors.
The Chinese-made PSU that accompanies most inexpensive tube microphones works relatively well, although its output voltage can drift, leading to subtle changes in the harmonic structure of the sound. To get the most out of the V-251, we recommend upgrading to our VPS1 supply, which provides tightly regulated voltage, superior filtering, and slow ramp-up power to extend the life of the tube. It allows B+ and heater voltages to be set independently via internal trimpots. The VPS is available as a fully built, tested, and warrantied unit, and as a circuit kit to upgrade an existing compatible power supply.
V-251 vs 12-251
How does the V-251 differ from our 12-251?
Both are premium DIY tube mic kits based on vintage models. Both use the 6072 tube (selected for low noise and low microphonics). Both deliver exceptional performance, far above what the price point would suggest. But they differ in component selection, topology, features, and specifications:
- The V-251 is a single triode, whereas the 12-251 uses a dual triode/CCDA topology. The V-251 is a more authentic copy of the original 251 circuit.
- The V-251 circuit has 6dB lower output.
- The V-251 circuit has up to 12dB higher second harmonic coloration, and therefore sounds more "vintage" / has more "vibe" or "tube sound."
- The V-251 kit is easier to build, primarily because we've eliminated nearly 50% of the wire joints.
- The V-251 circuit requires a higher-ratio transformer than does the 12-251 circuit. We use a T-14 here rather than our BV8-style 6.5:1. Both transformers provide excellent performance, but they convey subtly different character to the sound.
- The high-frequency rolloff "EQ" capacitor in the V-251 is socketed, making high-frequency tuning much easier.
- The V-251 provides a 10dB pad and a high-pass filter via external switches.
- The V-251 uses a film-and-foil output capacitor. We did not have room for such a capacitor in the 12-251 kit; it uses a high-grade metallized output capacitor.
In practice, both circuits offer performance rivaling commercial mics priced above $2000. The V-251 is easier to build, has additional features, and has more "tube sound" (even-order harmonic coloration). The 12-251 circuit has higher output, and therefore requires 6dB less preamp gain on quiet sources.
Which of these circuits best suits your needs depends on what you record, and what features you need. That is, neither is objectively "better." These two models sound different and excel at different things.
International power cords
US and Canadian customers will receive an IEC power cord with this kit. The power supply has a 115VAC/230VAC switch and can be used anywhere in the world, but we stock IEC cords only for US/CA. Therefore, V-251 orders shipped elsewhere will not include an IEC cord.
Hear the mic
Charlie and Ernesto at Ultimate Studios recorded guitar, bass, drums, and tambourine, making a complete song, with just one Platinum Edition V-251. Watch the session here:
(Episodes 2 and 3 will cover piano, organ, and vocals. Subscribe to Ultimate Studios' Youtube channel to see those.)