What is B, P, and G for tube amplifier output transformer?

We had been asked the questions that what B, P, and G for tube amplifier output transformer is. Maybe it is a simple question for tube amplifier audiophiles, there a brief for it below.

The primary of tube amplifier output transformer generally has two, three and five connection terminals.

The circuits of single tube type class A amplifier Among them include:

1. The primary is 2 connection terminals, P is connected to the screen, B is connected to B+ (that is, DC high voltage power supply)
2. The primary is 3 connection terminals, P is connected to the screen, G is a Ultra-linear tap (connected to the second gate of the power amplified tube such as 6P6P, 6P1, 6P14, etc.), B is connected to B+ (that is, DC high-voltage power supply)

 

Push-pull circuit:

1. The primary is 3 connection terminals, the transformer primary has two P terminals, and one B terminal, two P terminals respectively is connected to the screen of tube No and No2, B then connected to B + (that is, high-voltage DC power supply).Here, tube No.1 and No. 2 are two push-pull arms, same as below.
2. The primary five connection terminals, the five primary connection terminals of output transformer are: P1, G1, B, G2, and P2. Among them, P1 is connected to the screen of tube No. 1, G1 is connected to the ultra-linear tap of tube No. 1, P2 is connected to the screen of tube No. 2, G2 is connected to the ultra-linear tap of tube No. 2, B is connected to B+ (that is, DC high voltage power supply). There is an example below for push-pull circuit.

 

IWISTAO HIFI MINI Tube Hybrid Amplifier Bluetooth 4.0 2x28W Output 6N1 Preamp APT-X Black

 IWISTAO HIFI MINI Tube Hybrid Amplifier Bluetooth 4.0 2x28W Output 6N1 Preamp APT-X  Black

This is a mini tube hybrid amplifier, and support Bluetooth 4.0, apt-x, also it has 2 groups RCA inputs. Here, it play music from CD player, there is a demo below.

IWISTAO HIFI MINI Tube Hybrid Amplifier Bluetooth 4.0 2x28W Output 6N1 Preamp APT-X 115/230V Black from IWISTAO HIFI MINIMART1 on Vimeo.

You can use it to play lossless music formats music or network streaming with music player which is compatible with APE or FLCA music format , to enjoy funs of HIFI music. We recognize it is a better companion of your smart phone, tablet PCs and other mobile devices to enjoy wireless fidelity music.

（It played under Bluetooth wireless connection）

   

It is Hybrid designs that Wistao Bluetooth music base station, its preamp adopt 6N1 dual triode tube, power amplifier using high-power integrated IC. This design combines mellow and beautiful sound of tubes with feature of high-power output of high-power integrated IC, its maximum power is up to 2 x 28W, enough to meet your listening needs.


Also simple design of two switches, one is Bluetooth input switch, the other is RCA input of CD signal. It’s up to you to choose using Bluetooth signal input or RCA line input. The right of volume knob allows you to adjust volume of speakers. The rear of Bluetooth music base station is equipped with a banana plug line input, and can switch freely according to your needs, to switch CD input mode.

More details, please find below

IWISTAO HIFI MINI Tube Hybrid Amplifier Bluetooth 4.0 2x28W Output 6N1 Preamp APT-X 230V Black