Golden Age Premier GA-8000 | Tube Microphone

The printed circuit board used is a gold-plated ROGERS ceramic board. This type of circuit board is usually used in high-end aerospace communication products. The cost is about twenty times higher than an ordinary printed circuit board. By disassembling a C800G and turning the capsule over to a manufacturer with more than twenty years of experience in making microphone capsules, the manufacturer was able to produce a capsule that matched the characteristics of the original capsule. The capsule used in the GA-8000 can handle a higher sound pressure level than the original and has almost the same sound character. To ensure a long tube life, we use a NOS GIFTE 6AU6 tube from France, which has a maximum anode voltage of about 300V. The tube in this circuit has an anode voltage of 90V and generates more heat than tubes in many other tube microphones, which typically use voltages between 35-50V. The higher voltage used in the GA-8000 increases heat dissipation, so the active semiconductor cooling system is an important element of the design. The power supply of the classic 800G uses two 6AU6 tubes as rectifiers for the high voltage rail. They work as pseudo diodes by connecting all the grids to the anode, which outputs about 290V. After many listening tests comparing a tube rectifier circuit to a solid state circuit, the latter was preferred. The added advantage is that there is no need to worry about replacing tubes in the power supply. The metal resistors and electrolytic capacitors from Japan are special audiophile types. The coupling capacitors are Siemens EPCOS from Germany.