Golden Age Premier GA-47 MKII Classic Tube Microphone




Golden Age Premier GA-47 MKII Classic Tube Microphone

The Golden Age Premier GA-47 MKII has been born from a lot of hard work and real world testing and the MKII version has been further refined. The end result is a microphone with a very sweet character that should appeal to a great number of users and a microphone that can be used for the most demanding recording tasks. It has proved itself to be a great all rounder, this is not a “vocal-only” microphone.

The GA-47 MKII is not a product that will be built in huge quantities on a big assembly line. It´s a product that is built by hand, fifty units at a time in a small workshop by skilled and dedicated staff.
It uses very high quality components in the whole build to achieve the goal of offering classic U-47 qualities.

I believe that the level of quality and dedication that the GA-47 MKII provides, would normally come at a very high cost, in the world of U-47 clones. To make it available to many more users, we have decided to sell the GA-47 MKII at a very competitive price point.

Bo Medin, December 2017


GA-47 MKII build info

The microphone body is made of brass, the grille is made of iron.

The grille, which is a critical component affecting the sound character, is similar to the one in the Neumann U47. 

The capsule for the GA-47 MKII is designed to provide the requirements of modern day recordings by mixing the character between a vintage K47 capsule and one from a K67-style capsule with a wide frequency response and high sensitivity. The result is a truly great sound.

Being a dual-sided capsule, it provides the GA-47 with both cardioid and omni polar patterns.

In order to get a good consistency between units, for each production run of fifty GA-47 microphones, approximately 200 capsules are evaluated in order to find 50 with specifications that lie within the tight tolerances.


* Backplate material: brass
* Capsule diameter: 35mm
* Membrane diameter: 27mm
* Membrane material: 6 micron gold-coated mylar.
* The capsule is mounted in a special way to minimize the effect from physical vibrations.
*The sensitivity of the front and back side of the capsule do not differ more than 0,3 dB. The sensitivity between different capsules do not differ more than 0,5 dB.
* The tight manufacturing tolerance leads to a very good consistency between different GA-47 MKII units.
* The capsule is specially designed to complement the electronic circuit of the GA-47 to achieve a frequency response curve with a nice balance between the high, middle and low frequencies.


The GA-47 MKII uses a NOS Telefunken 800 series super low noise pentode tube connected in triode mode in order to decrease distortion and noise. This tube is a modern glass derivative of the VF14M used in the vintage U-47.


The GA-47 MKII is designed with a 6.5:1 dual bobbin transformer by a reputed transformer factory. It is a replica of the BV8 transformer used in the vintage Neumann U47. It uses a high quality core material.


The coupling capacitor is made in the United Kingdom, the brand is Ciarit, the same type used in the famous and very expensive B&W Nautilus loudspeaker. It is an axial capacitor made from MKP material with copper pins. It has a delicate, full sound and wide frequency response.

Other used capacitors are MIAL polystyrene film types with very low loss. The resistors are ALLEN BRADLEY carbon film made in the USA with a vintage warm sound.


The electronic circuit is built with point-to point wiring on an expensive Rogers circuit board. Teflon insulated, silver plated copper wire is used for the internal connections.


The vintage style power supply uses a high power R-style transformer with a low noise level and minimal stray field. The electrolytic capacitors are of a high quality audio style type.

A simple but effective circuit uses dual-stage filtering for the filament voltage. The high voltage is precisely filtered and stabilized using an ON semiconductor zener diode.

A -10 dB PAD switch on the power supply for high SPL instrument recordings like kick drum


The cable is specially produced using 99,99% pure oxygen-free copper, teflon insulation, tin foil and 98% kitmesh, producing a high density cable shield. It has a very open and smooth sound. 
The connectors are gold plated.


The circuit used in the GA-47 MKII is similar to the U-47 but the component values have been adjusted to accommodate the EF800 tube.
The polar pattern switch is located on the power supply allowing for easy adjustment.
The circuit used for the power supply is also similar except for the addition of a zener diode to ensure the voltage and current are stable.
The connectors are gold plated. All three connectors are placed on one end of the power supply to facilitate connections.


Frequency Response: 20Hz20KHz
Polar pattern; Cardioid and Omni-Directional
Sensitivity: 12mV/Pa
Rated Impedance: 200 ohms
Equivalent Noise Level: 10dB
Max S.P.L: 140dB

The GA-47 MKII is housed in a alluminium flight case with power supply, mic to psu cable (black, not red as shown in picture)  shock mount and wooden box for the microphone.