The input voltage amplification stage is served by an amplifying triode electron tube, and a two-stage common cathode resistance RC coupling amplifier is combined. The two-stage voltage gain can reach more than 40dB before the negative feedback is added, and can greatly increase the input audio signal amplitude
At the same time, inter-stage negative feedback is set between the input tube cathode and the power amplifier output.
Power amplifier stage design :
The amplifier supports Bluetooth input and can be easily paired with Android, iPhone, iPad, Tablet PC and other devices.
The power amplifier stage is composed of a standard class Class AB1 power amplifier circuit. The power amplifier tube to screen load impedance is 6 kohms, and the plate voltage is 375V.
Using only the gate negative bias mode, the zero-signal push-pull two-plate electrode power is 85mA, and the large screen current increases to 150mA. Rated output power is l6W, high power can reach 22W.
Independent Bluetooth antenna
4.0 Bluetooth HiFi Module
Support headphones to switch output, is a tube headphone amp
Bluetooth tube amplifier features:
Pure bile, pure hand-made, the whole machine adopts scaffolding welding.
Use two high quality wide frequency response EI output transformers.
Use an EI-type high-quality audio-dedicated power transformer developed specifically for this purpose.
In the previous stage, two 6N1 vacuum tubes and one 12AX7 vacuum tube were used.
Two EL34 vacuum tubes were used as AB1 push-pull power amplification in the later stage.
With headphone output function. Directly connected to headphones
Select Japan ALPS high-end potentiometer.
Easy to install plug-in vacuum tube protective cover.