E508 high-power Class A amplifier board (refer to the circuit of the Golden Voice E550)

Product details:

1. Using the original J162/K1058 field-effect tube bile taste tube, 2SA1930 2SC5171, MJE340/MJE350.

2. The coupling inter stage capacitor adopts German imported WIMA capacitor 3.9UF, with natural sound and wide sound field

3. Five ring metal resistors are selected as resistors, and the main circuit uses five ring metal film resistors with an accuracy of ± 1%, ensuring good signal-to-noise ratio of the entire machine.

4. The PCB adopts 1.6mm thick double-sided board, 2.0A copper thickness, and full tin spraying process to ensure good passing performance of large and small currents. First class PCB quality.

5. This board adopts the advanced C1237 speaker protection circuit, effectively eliminating the impact sound of power on and off and the DC output protection function, making your speaker safer.

6. The wiring layout of the entire circuit board is quite rigorous and reasonable, and the overall PCB wiring adopts a one point grounding method. This power amplifier board works stably

Reliable, high output power; The sound is beautiful and round, with a spacious soundstage. Strong sense of three dimensionality, stable and powerful low-frequency response, with a comparable signal-to-noise ratio

Excellent, with a wide dynamic range; Clear details and excellent transient response, capable of playing various types of music with ease, suitable for home playback environments

There is a very good performance in the environment.

Basic parameter requirements:

1. Power parameters: One set: DC+-45V (AC: Transformer 300W dual 32V, rectifier board required)

Another group: Single AC12V-15V (note: each board is independently powered by a single AC12V-15V power supply, that is, one board is powered by a single AC15V power supply)

2. The power amplifier board can adopt a master-slave integrated power supply. When the master-slave integrated power supply is used, each channel adopts a voltage of 28-32V and a current of 6-8A. The official recommendation is 70V DC, so our maximum working voltage is not more than 90V, which is positive or negative 45V. The transformer outputs AC 28-32V.

Measured under a Class A load of 80W and a load of 4 ohms

4. Speaker impedance: 4-8 ohms.

5. This circuit is easy to debug. Simply adjust the static current, connect a multimeter to the positive pole, set the multimeter to 10A or 20A, and adjust potentiometer VR1 clockwise to adjust the current to 1.5A. This board has no temperature drift and does not require repeated adjustment. This debugging is based on the recommended radiator size parameters in this article. If the radiator is too large or too small, the debugging will be changed. If the radiator is relatively large, the maximum static current should not exceed 2A. If the radiator is too small, the radiator temperature should not exceed 60 degrees. At any point, the static current must be reduced to ensure safety. Or test the current at point AB to calculate the total current. It is recommended to use AB voltage of 30-40 MV

6. Heat sink requirements: 300 X 100 X 50 (length). Wide. Recommended tooth height: above 2KG

7. Dimensions of the board with heat sink: 269 * 88MM

8. Weight: 0.25KG+0.25KG