The high and low pressure switch is designed to be easy to use, and the high voltage can be turned off without load ; Current monitoring, mainly displays the 300B screen current, so as to check the 300B aging status.
The vaccum tube holder adopts a shock-absorbing structure to prevent the electronic tube filament from shock by external forces ; Fully manual symmetrical configuration, including voltage stabilizing circuit e.2.0 Pure iron paint cabinet for effective anti-interference against magnetic field generated by transconductance transformer.
300b used the early simple pentode one-stage drive, and the gain is not as large as some combined or two-stage and three-stage drive. But the first-level advantage is that the pure class a amplifier can be matched with different external pre-amplifiers without excessive microphone effects, self-excitation and low-frequency noise caused by excessive gain. In the absence of a preamp, you can really hear different types of 300b real sounds.
