TG version 1969 power amplifier with power supply

This is an amplifier board based on the 1969 amplifier circuit, which solves the problem of complex power supply. It also has very low noise floor, clear high and low frequencies, low production cost, and simple circuit debugging, making it the perfect choice for beginners building their first high-power amplifier.
Here's a breakdown of the circuit structure: The input uses a 12V switching power supply or a 12V battery. First, it's boosted to over 30V using a 494 boost circuit, then regulated to 30V by an internal linear power supply. A linear power supply is used because it significantly reduces ripple, thus minimizing noise floor.
Below is a picture of the finished circuit board
 
. Note that the heatsink for the switching transistors should be as large as possible, as they generate a lot of heat during operation. Ideally, a cooling fan should be added.
Speaker selection is also important; it's recommended to use one tweeter and one woofer per speaker group for higher sound quality. However, the speakers need to be made separately.
Next is the crossover construction. Here, we'll use the simplest LC crossover principle. Then, we'll adjust the preamp using a self-made professional tuner,
install speaker terminals,
and construct the amplifier main unit terminals. Here's
a final product demonstration
. Let me mention some key circuit points
. Although most are written on the schematics, some points still require attention: First, strictly control the temperature of the two heatsinks. Excessive temperature can cause tube failure! If necessary, a cooling fan must be added for forced air cooling!
Second, power supply selection. The input voltage needs to be between 11-15V (a 12V switching power supply is sufficient, but the current must be ≥15A; it's best to use a switching power supply without a cooling fan, as the internal fan of a switching power supply is very noisy!). The amplifier heatsink fan should also ideally be a high-airflow, silent fan (the higher the air pressure, the better). Insufficient airflow is equivalent to not having one at all! If the input voltage is too high, the board will fail; if the input voltage is too low, it will affect the output power. Also, if you want to use the tone board as a preamp adjustment, I suggest powering it with a separate power supply or adding an isolated power supply (I previously used a switching power supply to power both the tone board and the amplifier board simultaneously, which triggered the tone board's protection circuit; without it, the board would probably have exploded). Alternatively, you can use the open-source mini audio regulator I released; here's the link: https://oshwhub.com/huoying123456/mini-audio-regulator
Finally, here are the test and assembly videos. Assembly video link:
https://www.bilibili.com/video/BV1dE421A7rT?t=17.6
Test video link
: https://www.bilibili.com/video/BV1NMvjeKE3M?t=1.9