Tube active speaker 01

In order to pursue a pure and soft tone, a pure Class A push-pull power amplifier should be used in the power amplifier settings .     The low Class A push-pull power amplifier is suitable for two-way speakers composed of 6 and a half inches. The 20W Class A push-pull power amplifier is suitable for three-way or two-way speakers composed of 8 inches. Its electrical power is similar to that of the tube power amplifier. The principle is shown in Figure f)-5-6 and Figure 9-57.     The base plate of a 20W Class A push-pull power amplifier is shown in Figure 9-58. When making a low power amplifier, the reference size can be reduced. The power transformer, output transformer and all electronic tubes are installed on the base plate , and other components are installed below the base plate. The four jacks on the base are: power switch and volume control; power inlet; jack for output to another speaker; and speaker input jack. The characteristic curve of     a Class A push-pull power amplifier is shown in Figure 9-59. Show. The power amplifier works in the DC part of the gate voltage-screen current characteristic curve . The push voltage input to the gate does not exceed the negative voltage area of ​​the gate at the maximum value of the positive half cycle, and it cannot cause the negative voltage to reach the negative voltage during the negative full cycle. The voltage value is too low, so that it reaches the curved part of the screen flow curve at the screen flow cutoff point and causes distortion.