Wunder Audio CM12 S

The Wunder Audio CM12 S Multi-Pattern Tube Microphone is a historic replica of the renowned AKG C12 vintage tube microphone, featuring capability of producing 9 different polar patterns. The CM12 S includes a CK12 capsule, a Hiller T14/1 transformer and a 6072a vacuum tube, all built to original specifications and true to the vintage C12. Our CM12 S is designed to reproduce an audio signal with the detail, clarity and character of the original C12.

The C12, AKG’s best-known tube condenser, is regarded by many as one of the finest microphones ever made and our CM12 S lives up to this notion with its principal sound creating components: the capsule, the transformer, the tube, the grille size and the screen mesh.

Grille

Some of the most important sound capturing components of the CM12 S is the grille size and screen mesh. Our CM12 S grille, as well as all the mechanical components in the CM12 S are true to the vintage mic and are made to the exact specs as the original C12, down to the smallest of machine marks. The grille is made like a piece of fine jewelry, as it is hand brazed, polished, and bright nickel-plated.

The grille’s open mesh captures the ears of those who were spoilt by the luminescence and transparency of the original C12.

Capsule

The Wunder Audio CM12 Suprema employs a true to vintage CK12 capsule with 6-micron Mylar. It is a side-address, large-diaphragm design based on AKG’s CK12 capsule. The CK12 dual membrane, dual backplate capsule was first Introduced in 1951 as AKG developed this completely new type of complex backplate. It is a 1″ membrane that is fully metalized. This freely vibrating membrane will have a lower LF cutoff than any center fixed membrane like the KK47 or KK67. The CK12 also has a unique system of dual, asymmetrical, separated resonant backplates (each backplate is itself a resonant chamber), which is what gives it a very flat midrange and 10-12 kHz peak. The original CK12 capsule is widely considered to be one of the finest condenser microphone capsules in history.

In 1953, an Austrian company, AKG revealed the now-legendary CK12 microphone capsule, and became one of the two dominant forces in the manufacture of commercial condenser microphones. This new capsule became be the basis of their bestselling AKG C12 microphone.

Transformer

The CM12 Suprema uses a period correct Hiller T14/1 transformer wound to the Braunbuch specification, using laminations made from the identical nickel alloy mixture as used in the historic Hiller T14 transformer.

Tube

The Wunder Audio CM12 S tubes are hand tested NOS GE 5-star 6072A:

• 6.3 volts DC filament voltage,
• 120 volts DC plate voltage

The GE 5 Star 6072A is one of the finest 6072 tubes ever made. In fact, the GE 5 Star 6072A’s are the only 6072 (12AY7 variant) tubes recommended in high-end applications. The primary special purpose of a 6072 is its super low noise and microphonics. That is why these tubes are important in microphones and first stages of high-end audio equipment. These special purpose dual triode tubes are equipped with spiral wound heater filaments to eliminate hum and have to pass rigorous screening for noise levels.

Capacitor

We’ve optimized our passive components to achieve a true audiophile performance. While audiophile equipment is usually referred to at the end of the chain in recording, we feel that it is most important that the first link in the recording chain, the microphone, be the best attainable. To be able to listen to the best possible recording, you must be able to record the source with minimal amounts of noise and distortion and be able to accurately capture every nuance of the sound. We’ve enhanced our true to vintage microphones by utilizing the Suprema Silver Gold Oil capacitor which is the highest quality capacitor available today. More importantly, sonically the CM12 S capacitor stands out due to its wonderful natural singing and exceptional micro dynamic. Capacitance: 1uF; Dielectric: Polypropylene Metallization  99.99% silver, 1% gold; Purity of silver: min. 99.97% typ. 99.99%; Purity of gold: min. 99.97% typ. 99.99%”.

Sound: At this level we are talking about a really serious capacitor, relative to other exotic types. They are richer and better layered and they seem more open and more spatial. Mundorf Silver Gold Oil really excels in image depth – call it bowling alley depth! A slight hint of top-end air, this probably contributes to the perceived spatiality and micro-detailing. These capacitors are so quiet and really let you look very deep into the recording!

This results in a modern-vintage sound where the spectrum opens up, adding emphasis to the sound staging and creates a greater sense of air and transparency, without the impression of a diminished mid and lower-end response. The outcome is a less grainy and a much more fluid sound. The focus is tighter and sharper.

Power Supply

The new generation tube Microphone PSU is proprietary to Wunder Audio and is an upgrade from the vintage tube mic PSU’s used for the 1960’s era Neumann design. Our upgrade gets a clean and stable DC voltage to the mic and shields the influx of Wi-Fi and RF interference with 100 percent reliability.

We’ve engineered our PSU to the equivalent of the technology incorporated in top tier audiophile systems, using a duel-pole neutral-fusing design. The PSU can be plugged into any voltage in the world without having to jumper a voltage setting switch.

Inside, we’ve incorporated extremely accurate 30 turn trim pots so we are able to fine-tune all of the voltages. Most other power supply designs either do not have a voltage trim or use a single turn pot, which is susceptible to drifting.

For the most reliable pattern switching, the CM12 S PSU uses a military spec Grayhill switch.

Box and Carrying Case

Your Wunder Audio CM12 S is nestled in velvet and softly secured in place in a foam-lined quarter sawn oak box that is clasped and hinged. This box then is safely incased in a precision velvet-lined thick foam tweed case that also holds your PSU, your swivel mount, and your cables. The tweed carrying case is a work of art in itself; it uses the same Fender tweed found in a vintage fender guitar case which amplifies the vintage period of the vintage-style CM12 S microphone, and it is trimmed with top grain leather and fine stitching. The CM12 S case has a strong leather handle and combination lock to keep your mic secure. This case can be sold separately.

Technical Data

• Frequency Range: 20 to 20,000 ± 2 dB
• Directional Characteristics (nine different positions):   omni-directional.
• Cardioid: better than 20 dB front-to-back ratio at 180° sound incidence,
• Bi-directional: 20 dB front-to-back ratio
• Sensitivity: 1.0 mV/µbar (–60 dB re 1 V/dyne/cm2), unloaded (200 ohms)
• Equivalent Noise Level: less than 20 dB
• Tube Complement: 1 x 6072, 6.3 volts DC filament voltage,
• 120 volts DC plate voltage
• AC Connection: 110/125/145/220/245 volts AC at 50/60 cps

Upgrade Your Mic 

All previous versions of the Wunder Audio microphones can be upgraded to the Surprema.

Visit the Wunder Audio website.