Where is the problem with the loud current of
First of all, you must distinguish where the current sound comes from, whether it is generated by the computer or the audio cable, or the sound itself. The way to distinguish is also very simple. You first use a DVD player or CD player as the input source, turn on the audio and listen for the current sound. If not, the current sound must be generated by the computer. 1. Poor microphone contact sometimes introduces hum, and see if there is any change in the situation when the microphone is unplugged or replaced. 2. Poor power supply filter will also have hum, see if there is filter capacitor failure or capacity reduction. You can try one in parallel with the same specification. 3. Check the input circuit for poor shielding or problems with shielded wires. The shielded wire should be grounded at one end and empty at the other end. This can prevent hum caused by interference signals at both ends of the shielded wire. 4. Judge whether it is the hum produced by the pre-stage or post-stage. What is the problem with the large current noise of the power amplifier? Four ways to eliminate the current noise of the power amplifier Four methods of eliminating power amplifier current sound A lot of times we are using power amplifiers, in some cases there will be current sound, so is there any way to eliminate this situation? Today, the author will analyze the four methods of eliminating the current sound of the power amplifier in detail. Method one: Electromagnetic interference Electromagnetic interference can be divided into power transformer interference and stray electromagnetic interference. specific method: 1. Power transformer interference: due to the magnetic leakage of the power supply of the multimedia speaker, the effect of adding a shield to the transformer is very obvious when conditions permit, and the magnetic leakage can be blocked to the greatest extent. The shield can only be made of iron materials Make. We should try to choose products with big brands and solid materials. In addition, using an external transformer is also a good solution. 2. Stray electromagnetic interference: It is relatively common that speaker wires, frequency dividers, wireless devices or computer hosts will all become sources of interference. Keep the main speakers as far away from the computer host as possible and reduce the surrounding wireless devices. Method 2: Do the work on the connection cable and connect the interface well specific method: The broadcasting line and the wiring should be good. There should be no disconnection and contact with the power amplifier shell. Do not tie the wires together with trapped wires. Use good quality wires. Tighten the wiring. The power cord is best connected to the live wire and zero. Line 2 follows, each interface must be well connected, so there will be no noise Method three: analysis of fault problems, corrective treatment specific method: 1. First determine whether there is hum when the audio input is not connected or the input plug is not inserted. If it is, it is a problem in the machine. 2. Problems in the machine First, check whether the filter circuit is effective. It can be tested by measuring the capacity of the filter capacitor or by paralleling capacitors of the same capacity. Replacing a good capacitor can solve this problem. 3. Caused by unreasonable wiring: check whether the wiring of the input wire and the ground wire is reasonable. Check whether the shield of the transformer is grounded, otherwise there will be hum. 4. Another point is that the shield layer of the shield line from the audio input socket to the power amplifier input terminal should be grounded at one end. Do not use its shield layer as the low end of the signal to transmit audio signals, otherwise it is easy to produce hum. Method 4: Treatment under poor contact The current sound of the amplifier may be due to poor contact with the 'earth' of the amplifier input circuit or the previous circuit, such as the loose end of the volume potentiometer, the poor grounding of the housing, and the common end of the signal line between the front stage and the back stage is broken or contacted Bad etc. Of course, the quiescent current of the final power amplifier tube of the ordinary power amplifier circuit will also cause current sound. specific method: 1. The power transformer has magnetic leakage and needs to be shielded. 2. The capacity of the power supply filter capacitor becomes smaller. 3. The filter capacitor of the audio input of the amplifier is open. 4. Ground the power amplifier's shell.