Features: Maximum SPL: 136dB Frequency range: 20Hz-20KHz Signal/Noise: 85dBA Impedance: ＜200 Ohm Sensitivity: 16mV/Pa Microphone dimensions: 50mm(diameter) * 250mm (length)  Microphone weight: 0,6kg PSU dimensions: 200mm (length) * 100mm (width) * 100mm (height)  PSU weight: 1,5kg

Mic body and grilleThe mic 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 U47. Capsule The capsule for the GA-47 is designed to provide the requirements of modern day recordings by mixing the character between a vintage K47 capsule and the 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 one, 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 50 pcs GA-47 units, approximately 200 capsules is evaluated in order to find 50 capsules with specifications that lie within the tight tolerances. Specifications: Backplate material: brass Capsule diameter: 35mm Membrane diameter: 27mm Membrane material:6 micron gold-coated mylar. The capsule is mounted on a 7 mm thick aluminium plate 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 will lead to a very good consistency between different GA-47 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. TubeThe GA-47 uses a NOS Telefunken 800 series super low noise pentode tube connected in triode mode in order to decrease distorsion and noise. This tube is modern glass derivative of the VF14M used in the vintage U-47. Output transformerThe GA-47 transformer is especially 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 U47. It uses a high quality core material. Capacitors and resistorsThe coupling capacitor is made in 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 a wide frequency response. Other used capacitors are MIAL polystyrene film capacitors with very low loss. The resistors are ALLEN BRADLEY carbon film resistors made in the USA with vintage and warm sound. Mic interior and cablingThe electronic circuit is mainly built with point-to point wiring and the ground connections are tied together using an insulated soldering.Teflon insulated, silver-plated copper wire is used for the internal connections. Power supply transformer and electrolytic capacitorsThe vintage style power supply PSU uses a high power R-style transformer with a low noise level and a 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. Mic cableThe cable is specially produced using 99,99% pure oxygen-free copper, teflon insulation, tin foil and 98% kitmesh, ie with a very high braided density of the cable shield. It has a very open and smooth sound. The connectors are gold plated. Mic and psu circuit in relation to the original micsThe circuit used in the GA-47 is similar to the U-47 but the component values has been adjusted to fit the EF800 tube. In order to achieve the best sound quality, no coupling capacitor is used between the capsule and the tube, just like in the classic U-47 microphone. Even the highest quality capacitor will affect the sound. The small price to pay is that it´s then not possible to achieve a Figure-8 polar pattern. For users who would prefer to accept that sound quality degradation, the GA-47 can be modified to have a Cardioid and Figure-8 pattern. The polar pattern switch is located on the power supply allowing for easy sound comparisons. The circuit used for the power supply is also similar except for adding a zener diode to assure the voltage and current stable.The connectors are gold plated. All three connectors are placed on one side to facilitate handling and placement.

Features: Vintage Style electronics. No integrated circuits in the signal path. Maximum gain in mic mode is 80 dB, enough to handle passive ribbon mics with quiet sound sources. Gain switch range is 20 - 80 dB. Line mode switch, gain is reduced by 30 dB in line mode. Selectable two position high frequency air eq boost mode, 3 or 6 dB @ 30 kHz. Selectable 6 dB/octave high pass filter at around 80 Hz (HP1) or 200 Hz (HP2). 14 dB output pad allowing the user to overdrive the output stage and transformer. Switchable impedance in mic mode, 1200 or 300 Ohm, will change the tone of most mics. The input impedance in line mode is 10 kOhm. Switchable phantom power and absolute phase. A high-impedance instrument input for any sound module, electric guitar or bass. A simple but effective 4-step LED output level meter. The output level control makes it possible to make fine gain adjustments and also to overload the main gain stage(s) for more character. Combo XLR/TRS input jack and separate output XLR and TRS jacks for flexible connections. Insert jack for inserting EQ´s and other units. Selectable 600 Ohm output termination. Classic style knobs and buttons. Prepared for mounting one or two units in the UNITE PREMIER rack kit. It can also be mounted in one of the other UNITE rack kits and combined with the red and black Golden Age Project products. Connector free internal wiring, all connections except the ones to the gain switch --are soldered for the purest signal and most longterm stable signal path. UK made Carnhill input and line output transformers. Polystyrene capacitors in the amplifier circuits. Tantalum capacitors in the signal path. Beefed up power supply. Sturdy toggle switches with gold plated contacts. External power supply to avoid interaction with the audio circuits and transformers. A solid build quality that will last many years of normal use.

Features: Vintage Style electronics. No integrated circuits in the signal path. Maximum gain in mic mode is 80 dB, enough to handle passive ribbon mics with quiet sound sources. Classic 23-position Gain/Line switch with 5 dB steps and a gain range of 20 to 80 dB for mic and -10 to +20 dB for line. A two band LF (+/-15 dB) and HF (+/-20 dB) shelving equalizer with two selectable frequencies for each band. Inductor based +/- 15 dB midrange equalizer section with three selectable frequencies. The lowest one is selectable between 350 and 700 Hz. Switchable impedance in mic mode, 1200 or 300 Ohm, will change the tone of most mics. The input impedance in line mode is 10 kOhm. Switchable phantom power and absolute phase. A high-impedance instrument input for any sound module, electric guitar or bass. A simple but effective 4-step LED output level meter. The output level control makes it possible to make fine gain adjustments and also to overload the main gain stage(s) for more character. Separate combo XLR/TRS jack for the MIC and LINE input and separate output XLR and TRS jacks for flexible connections. Selectable 600 Ohm output termination. Classic style knobs and buttons. Prepared for mounting one ot two units in the UNITE PREMIER rack kit. It can also be mounted in one of the other UNITE rack kits and combined with --the red and black Golden Age Project products. Connector free internal wiring, all connections except the ones to the gain switch --are soldered for the purest signal and most longterm stable signal path. UK made Carnhill microphone input and line output transformers. The pcb is prepared for the Carnhill 9046M line input transformer. Polystyrene capacitors in the amplifier circuits. Tantalum capacitors in the signal path. Beefed up power supply. Sturdy toggle switches with gold plated contacts. External power supply to avoid interaction with the audio circuits and transformers. A solid build quality that will last many years of normal use