For audiophiles, audiophile is equal to burning money. For some audiophiles who are not very economically comfortable, playing with headphones is a good best way to have a fever without too much money. The reason is very simple. Generally speaking, it is difficult to buy low-quality audio equipment on the market for two or three hundred dollars, but you can buy a very good pair of fever headphones, and the frequency response and various indicators of the headphones are not inferior to high-end ones. The speaker unit is also the main reason why the headphone amplifier DIY is popular at home and abroad. In the headphone amplifier, generally excellent discrete component circuits have been seen on many domestic and foreign websites, and they are made by electronic tubes, but for general enthusiasts. That is to say, it is difficult to find the components, and the matching of the tubes is also a headache. The difficulty of making the main transformer of the electronic tube has been solved.
At the request of netizens, I have found some easy-to-make headphone amplifier circuits for reference for those with better hands-on skills. The circuit diagrams are from domestic and foreign websites and electronic magazines. If there is a violation of your copyright, please notify me and I will delete it.
LC-KING A (A) headphone amplifier circuit
The picture above is a circuit diagram. The circuit is very simple. The pre-amplification push is NE5532 or other types of OP, U2A is DC SERVER, which is used to stabilize the potential of the midpoint, and the push level 2SD882 is an NPN type power triode. Therefore, the amount of heat generated is large, and the current flowing through R11 and R31 can be adjusted by changing its resistance. The transistor should be added with a radiator during production.
LC-KING's class AB amplifier circuit
The picture above shows the class-A power amplifier circuit of LC-KING. The amplification of the latter stage consists of the pair of tubes 2SD882 (NPN) and 2SB772 (PNP) TL072 as DC servo circuits, which play a role in stabilizing the potential.
The amplification circuit of LC-KING is relatively simple, and it is not difficult to manufacture. It can be completed with a hole plate, and the transistor of the rear pole can also be replaced with other tubes. The power supply of the amplifier also has a great influence on the sound quality. Of course, the use of Watian power supply is very good. You can also use the servo power supply. The power supply of the original picture is a little complicated. The key is that some components are very biased, so they are not put on the Internet.
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Ear amp made with dual op amps such as OPA2604
The picture above is a popular amp with an operational amplifier on the Internet. Of course, you can use other dual op amps to replace it to get different sounds. The use of two amplifiers in the picture above can improve the current output capability, which can promote High impedance headphones, most high-end headphones are high impedance. It is more popular to use OP234 or OP2134 (dual op amp) as the headphone amplifier on foreign websites, because the performance of the op amp is good when it is operated at low voltage, so that it can be conveniently powered by batteries. Make a portable amp.
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ZEN amp
The above is the amp circuit of ZEN. It is also a circuit that the domestic enthusiasts are happy to make in recent years and are said to be used to practice listening to the ears. There are also PCB boards that are supplied online for assembly by enthusiasts. The author did not personally practice it. But there is a chance to find a component and want to give it a try.
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MOSFET Class A amplifier
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