排除杂音，播放流畅的济南音响打造最惬意的环境
2014-8-22 9:09:30 点击：
调音过程中，经常碰到不同程序的噪音问题，对于已经制作成形的电路板，以下几种方法可以根治或者降低济南音响产生的噪音。
Tuning process, often encounter the problem of noise of different programs, for making circuit board forming, the following methods can effect a radical cure or reduce Ji'nan audio noise.
一、后级功放板的电流哼声
Current hum a, back stage power amplifier board
1、将济南音响驳入功放，开启电源，挪动电源变压器位置直至哼声减弱，再用金属罩（可以是铁壳）和住固定。
1, the Ji'nan audio barge into the power amplifier, power, mobile power supply transformer position until the hum is weakened, and the metal cover (can be iron) and fixed.
2、如果变压器次级引出是排线，应将其拆开改作编织绞线。
2, if the transformer secondary lead is cable, should be open for woven wire.
3、将线路板上喇叭输出引线的负端焊下，在滤波电容之后的大面积接地铜箔处可以找到一噪音最低点焊接。
3, the negative terminal welding circuit board speaker output leads, in the area of the filter capacitor after the grounding copper foil can find a noise low welding.
4、增大或更换滤波电容。此方法极少用，笔者做过多次试验，证明±25V以上、功放末级电流2～7.5A的电源，滤波3电容值不小于3300μF均不会出现电流哼声。
4, increase or replace the filter capacitor. This method is rarely used, the author did many experiments, prove ± 25V above, power amplifier stage current power 2 ~ 7.5A, 3 filtering capacitance value of not less than 3300 μ F were not current hum.
5、改变功放板的安装位置，将散热器横置于变压器与线路板之间，起磁屏蔽作用，减弱电流哼声。
5, the change of the installation position of the power amplifier board, radiator transversely arranged on the transformer and the circuit board, magnetic shield, and reduce the current hum.
6、适当改变元件引脚高度特别是反馈电阻和耦合电容。分立元件组成的电压放大部分也应引起注意，它们的引脚高度离电路板面2～5.5mm最佳。
6, changing the component pin height especially feedback resistors and coupling capacitors. Discrete voltage components of the amplifying section should also be paid attention to, their pin height from the surface of the circuit board 2 ~ 5.5mm.
二、功放后级咝咝声
Two, the power amplifier stage hiss
1、取1000pF瓷介电容，在整流电路中的二极管上各并焊一只。滤波电容之后的正负电源支路与地之间各并入1～3只100μF电解电容和0.1μF的MKT电容。
1, take 1000pF ceramic capacitor, diode rectifier circuit in each and welding in a. Between the branch and the positive and negative power supply filter capacitor after each into 1 ~ 3 100 μ F electrolytic capacitor and 0.1 μ F MKT capacito
2、取容量在220～1500pF之间的薄膜电容并入信号输入端与地之间试听，选用咝咝声最小的一只电容；且播放一段熟悉的音乐，凭听感要求以不影响高频特性为准。
Film capacitor 2, the capacity of between 220 ~ 1500pF incorporation. Between the signal input terminal and the ground, the hiss one capacitor smallest; and playing a familiar music, by listening to not affect the high-frequency characteristics shall prevail.
以上的防噪方法是在切断前置输入来进行的。同样可以用于前置放大的降噪处理。
Anti noise methods above is to cut off the input to the front. Can also be used to de noise preamplifier.
三、济南音响 http://www.jnzqyx.com/ 功放前级的哼声
Three, Ji'nan audio power amplifier stage hum
1、将直流电源线路“+”端断开，串入100～300mH的电感，严禁虚焊。
1, the DC power supply line "+" end disconnected, serial in 100 ~ 300mH inductance, is strictly prohibited.
2、用塑料棒或竹筷子夹住音源输入端至前级放大板的引线，寻找一哼声最小处固定。
Lead 2, with the plastic stick or bamboo chopsticks and sound source input end to the front stage amplifiers, find a minimum fixed hum.
3、改变前置与后置放大板的接地点。若二者是用屏蔽线作连接的，应将屏蔽线一端的屏蔽网焊入后级输入端地，而另一端不接地。前置与音源输入接口的接线也如此，只在音源输入一端接地。这样，就不会形成接地环路，不会交连耦合出讨厌的哼声。
3, change the ground pre and post amplifiers. If the two is connected with shielding wire, shielding net welding should be shielded wire end into the later stage input, and the other end is not grounded. So also wiring pre and audio input interface, only the audio input end is connected to the ground. In this way, will not form a ground loop, no AC coupled out hate hum.
四、功放前级咝咝声
Four, the power amplifier pre hiss
主要出现在反馈式音调电路中，特别是搭棚焊接的，高频咝咝声严重。解决方法是用薄铜皮将其屏蔽起来，或者改抽成无源衰减式音调电路，可有效降低咝咝声。
Mainly in the feedback tone circuit, especially for welding, high-frequency hiss serious. The solution is to use the sheet copper shielding it up, or pumped into passive attenuation type tone circuit, can effectively reduce the hissing sound.
以上的几种降噪措施只限于晶体管、集成电路功放中应用。当然，电路底板的设计是至关重要的，诸如电源、音频信号走线、模拟地与数字等等。
Several measures of reducing noise above only used transistor, integrated circuit amplifier. Of course, the design of circuit board is very important, such as power supply, the audio signal line, analog and digital.
Tuning process, often encounter the problem of noise of different programs, for making circuit board forming, the following methods can effect a radical cure or reduce Ji'nan audio noise.
一、后级功放板的电流哼声
Current hum a, back stage power amplifier board
1、将济南音响驳入功放，开启电源，挪动电源变压器位置直至哼声减弱，再用金属罩（可以是铁壳）和住固定。
1, the Ji'nan audio barge into the power amplifier, power, mobile power supply transformer position until the hum is weakened, and the metal cover (can be iron) and fixed.
2、如果变压器次级引出是排线，应将其拆开改作编织绞线。
2, if the transformer secondary lead is cable, should be open for woven wire.
3、将线路板上喇叭输出引线的负端焊下，在滤波电容之后的大面积接地铜箔处可以找到一噪音最低点焊接。
3, the negative terminal welding circuit board speaker output leads, in the area of the filter capacitor after the grounding copper foil can find a noise low welding.
4、增大或更换滤波电容。此方法极少用，笔者做过多次试验，证明±25V以上、功放末级电流2～7.5A的电源，滤波3电容值不小于3300μF均不会出现电流哼声。
4, increase or replace the filter capacitor. This method is rarely used, the author did many experiments, prove ± 25V above, power amplifier stage current power 2 ~ 7.5A, 3 filtering capacitance value of not less than 3300 μ F were not current hum.
5、改变功放板的安装位置，将散热器横置于变压器与线路板之间，起磁屏蔽作用，减弱电流哼声。
5, the change of the installation position of the power amplifier board, radiator transversely arranged on the transformer and the circuit board, magnetic shield, and reduce the current hum.
6、适当改变元件引脚高度特别是反馈电阻和耦合电容。分立元件组成的电压放大部分也应引起注意，它们的引脚高度离电路板面2～5.5mm最佳。
6, changing the component pin height especially feedback resistors and coupling capacitors. Discrete voltage components of the amplifying section should also be paid attention to, their pin height from the surface of the circuit board 2 ~ 5.5mm.
二、功放后级咝咝声
Two, the power amplifier stage hiss
1、取1000pF瓷介电容，在整流电路中的二极管上各并焊一只。滤波电容之后的正负电源支路与地之间各并入1～3只100μF电解电容和0.1μF的MKT电容。
1, take 1000pF ceramic capacitor, diode rectifier circuit in each and welding in a. Between the branch and the positive and negative power supply filter capacitor after each into 1 ~ 3 100 μ F electrolytic capacitor and 0.1 μ F MKT capacito
2、取容量在220～1500pF之间的薄膜电容并入信号输入端与地之间试听，选用咝咝声最小的一只电容；且播放一段熟悉的音乐，凭听感要求以不影响高频特性为准。
Film capacitor 2, the capacity of between 220 ~ 1500pF incorporation. Between the signal input terminal and the ground, the hiss one capacitor smallest; and playing a familiar music, by listening to not affect the high-frequency characteristics shall prevail.
以上的防噪方法是在切断前置输入来进行的。同样可以用于前置放大的降噪处理。
Anti noise methods above is to cut off the input to the front. Can also be used to de noise preamplifier.
三、济南音响 http://www.jnzqyx.com/ 功放前级的哼声
Three, Ji'nan audio power amplifier stage hum
1、将直流电源线路“+”端断开，串入100～300mH的电感，严禁虚焊。
1, the DC power supply line "+" end disconnected, serial in 100 ~ 300mH inductance, is strictly prohibited.
2、用塑料棒或竹筷子夹住音源输入端至前级放大板的引线，寻找一哼声最小处固定。
Lead 2, with the plastic stick or bamboo chopsticks and sound source input end to the front stage amplifiers, find a minimum fixed hum.
3、改变前置与后置放大板的接地点。若二者是用屏蔽线作连接的，应将屏蔽线一端的屏蔽网焊入后级输入端地，而另一端不接地。前置与音源输入接口的接线也如此，只在音源输入一端接地。这样，就不会形成接地环路，不会交连耦合出讨厌的哼声。
3, change the ground pre and post amplifiers. If the two is connected with shielding wire, shielding net welding should be shielded wire end into the later stage input, and the other end is not grounded. So also wiring pre and audio input interface, only the audio input end is connected to the ground. In this way, will not form a ground loop, no AC coupled out hate hum.
四、功放前级咝咝声
Four, the power amplifier pre hiss
主要出现在反馈式音调电路中，特别是搭棚焊接的，高频咝咝声严重。解决方法是用薄铜皮将其屏蔽起来，或者改抽成无源衰减式音调电路，可有效降低咝咝声。
Mainly in the feedback tone circuit, especially for welding, high-frequency hiss serious. The solution is to use the sheet copper shielding it up, or pumped into passive attenuation type tone circuit, can effectively reduce the hissing sound.
以上的几种降噪措施只限于晶体管、集成电路功放中应用。当然，电路底板的设计是至关重要的，诸如电源、音频信号走线、模拟地与数字等等。
Several measures of reducing noise above only used transistor, integrated circuit amplifier. Of course, the design of circuit board is very important, such as power supply, the audio signal line, analog and digital.
- 上一篇：从”面相“中找出济南音响扩声设备的故障 2014/8/25
- 下一篇：高山流水遇知音，济南音响频段与音乐的美妙邂逅 2014/8/21
