All components on the board are brand new!
Considering the transportation safety and the buyer`s need for leads, the finished board potentiometers are not welded, and the buyer needs to weld your himself!
This product refers to the tone part of the British NAD3020 power amplifier. It is designed with double-sided gold-plated PCB (base plate 1.6MM, copper foil 35U thick). It is assembled with heating elements. The circuit is a single ended Class A amplifier. The amplifier tube is a Japanese original high magnification (HFE300+): 2SA992/2SC1845 special audio tube. The rear two pairs use special B647/D667 stereo couplers, the copper pin metal film resistor of Military 718 Factory, the new LM317/337 high-precision low-noise voltage stabilizing IC, the new revision and upgrade of nichicon Nikon 35V4700UF electrolytic capacitor, Panasonic Audio Master gold electrolysis, and ALPS high-quality potentiometer. The biggest feature of this tone is to adjust the high and low frequencies. The mid frequency has almost no change, and the low frequency is very elastic! High frequency is thin and not harsh! The tone is mellow and very durable! The effect is not comparable to the tone of the operational amplifier. High and low pitch adjustment range: low pitch+- 15DB, high pitch+- 10DB
Potentiometer distance from left to right: 40MM, 58MM
Line gain: 8 times
Size: 138 * 81MM
Voltage: AC: 24V -- 0V -- 24V
be careful! Brother, you must watch! 1: The power supply voltage shall not be lower than the AC dual 22V, 2: If you are only listening to the bare board, you must connect all the potentiometer enclosures with wires, and then connect them to the "GND" at the power terminal on the board so that there is no noise. Audio signal input must use shielded wire! If it is installed into the chassis, please refer to the "one point grounding" I passed on the signal to noise ratio of the finished machine installed in our shop: the high and low pitch potentiometers and the volume potentiometers are turned to the maximum, and the ear is close to the speaker to hear the low noise! Please do not doubt the signal-to-noise ratio of the board!
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