813 (FU-13) Vacuum Tube Amplifier Classical Diagram Circuit
Vacuum tube 813 belongs to antique one, which is a direct thermal beam shot tetrode with thorium tungsten cathode, graphite anode. In the radio equipment, it can be used for the oscillator power amplifier tubes, and its using frequencies are up to 30MC. When it is used as a power amplifier (such as Class AB), its output power is up to 300W or above, it is high reliable, excellent linearity, and not only does it perform tigers’ roaring and thunder exhaustive, but also can perform thin piano voice with detailed and delicate, it is the master of tube amplifier.
813 sound is very good, power and life are outstanding, air sense and sound field is far better than with that cannot be compared, you may not want to listen to small power output tube after listening tube 813. Due to its high power output, it can drive high power speakers that tube amplifier with lower output can't drive. It is the first choice to drive low-sensitivity, high-power and high-end speaker.
There are 813 (FU-13) Tube Amplifier Classical Diagram Circuits, only for your information.
More details, please find https://www.iwistao.com/products/vacuum-tube-813-shuguang-for-tube-amplifier-replace-fu13-high-power-output-quality-hifi-audio?_pos=1&_sid=d8f007fee&_ss=r