1Pair Hood 1969 Class A Power Amplifier Finished Board With Toshiba 5200 Large Tube Power

HOOD1969 is undoubtedly one of the most popular power amplifier circuits in history. It was designed in 1969 by the famous British audiophile J.Hood. There have been countless imitations in the world for decades. Some people use it to compare it with the 300B amplifier. The sound is toxic and I think most enthusiasts have already made a name for themselves.

Note: the old style new style with the factory shipping, the style is partly different, but the function remains the same, please buyer know, thank you!

With a filter capacity of up to 18000UF, the bass is full volume and abundant high current supply!

Debugging method:

The 1969 commissioning is divided into static current test and neutral voltage test.

1.The quiescent current was adjusted to the house, the default value is 1.2A. You can change the quiescent current by adjusting the 202 adjustable resistor on the board. Recommend 1-2A! Also, the quiescent current must be tested in series with the current input.

2. midpoint voltage test, the midpoint voltage must be half of the supply voltage, that is, the supply voltage is 18V, then the midpoint voltage should be 9V, the test is done with the DC voltage file, the red test pin is connected to the positive terminal of the output capacitor, and the black test lead is grounded. Line test can be! Adjust the resistor 204 so that the voltage is half of the supply voltage.

PCB size: 62 mm × 129 mm, symmetrical process design! Gold plated PCB, CNC complete inspection!

With Toshiba Big Tube and 1969, the output is even larger! Symmetrical design, beautiful appearance, the use of Fairchild original TIP41 sound is most positive, the output is selected German original Siemens capacitor!

The biggest shortcoming of 1969 should be that the heat is large and the power is small, but the general auditing of the indoor environment is sufficient. The owner himself also has a computer next to it. The sound has a charm, high density, good hearing resistance, no crossover distortion, sound. It feels much more sensitive.

Make sure you use the heat sink and fix it. Since 1969 is known to have a lot of heat, you need to insulate several pipes. The input can be connected directly to the AC transformer. The preset end point voltage is very small and the beginner can make a noise without adjusting it.

Toshiba original 5200 high power tube must be used!

It has the characteristics of small distortion, strong broth, dynamic and transparent sound. The bass is strong and flexible. It is obviously better than the ordinary triode TIP41C, 2N3055 and other versions of 1969. It is not tired for a long time. Another advantage is low heat generation and saving. The heat sink is very cool, especially in summer, and can not be baked like a small armor.

Voltage range of the transformer: AC12V to AC28V 2 lines, recommended 50W or more.

Design highlight 1: Use 5200 high precision high current voltage regulator output, the output voltage is more stable! Beyond LM317! Noise is even more inaudible

Design Highlight 2: Input with a thin film audio capacitor for better sound! Several specifications available

Design Highlight 3: Toshiba Tube 2SC5200 output! This tube has an output of up to 150W, which makes 1969 20W class A output! More than 2N3055! !

Delivery content:

1Pair hood 1969 class A power amplifier Finished board with Toshiba 5200 large tube output.