高峰纯后级功放原理图
功率放大器原理功率放大器原理图
功率放大器原理功率放大器原理图要说功率放大器的原理，我们还是先来看看功率放大器的组成：射频功率放大器（RF PA）是各种无线发射机的重要组成部分。
在发射机的前级电路中，调制振荡电路所产生的射频信号功率很小，需要经过一系列的放大一缓冲级、中间放大级、末级功率放大级，获得足够的射频功率以后，才能馈送到天线上辐射出去。
为了获得足够大的射频输出功率，必须采用射频功率放大器。
射频功率放大器是发送设备的重要组成部分。
射频功率放大器的主要技术指标是输出功率与效率。
除此之外，输出中的谐波分量还应该尽可能地小，以避免对其他频道产生干扰。
功率放大器原理高频功率放大器用于发射机的末级，作用是将高频已调波信号进行功率放大，以满足发送功率的要求，然后经过天线将其辐射到空间，保证在一定区域内的接收机可以接收到满意的信号电平，并且不干扰相邻信道的通信。
高频功率放大器是通信系统中发送装置的重要组件。
按其工作频带的宽窄划分为窄带高频功率放大器和宽带高频功率放大器两种，窄带高频功率放大器通常以具有选频滤波作用的选频电路作为输出回路，故又称为调谐功率放大器或谐振功率放大器；宽带高频功率放大器的输出电路则是传输线变压器或其他宽带匹配电路，因此又称为非调谐功率放大器。
高频功率放大器是一种能量转换器件，它将电源供给的直流能量转换成为高频交流输出。
在“低频电子线路” 课程中已知，放大器可以按照电流导通角的不同，将其分为甲、乙、丙三类工作状态。
甲类放大器电流的流通角为360o，适用于小信号低功率放大。
乙类放大器电流的流通角约等于180o；丙类放大器电流的流通角则小于180o。
乙类和丙类都适用于大功率工作。
丙类工作状态的输出功率和效率是三种工作状态中最高者。
高频功率放大器大多工作于丙类。
但丙类放大器的电流波形失真太大，因而不能用于低频功率放大，只能用于采用调谐回路作为负载的谐振功率放大。
由于调谐回路具有滤波能力，回路电流与电压仍然极近于正弦波形，失真很小。
简单音频功放电路原理图大全（六款简单音频功放电路设计原理图详解）
简单音频功放电路原理图大全（六款简单音频功放电路设计原理图详解）简单音频功放电路原理图（一）这款功放一声道只需17个零件，却收到了意想不到的效果，还音效果真实，频响平直，解析力高，且功率可以达到50W。
此功法电路可谓一装即成，特别适合初学者制作。
具体电路如图（只画出一声道），全机用1/2W电阻，C2和C4用瓷盘电容即可，Q5、Q6采用大功率管2SC5200，变压器容量大于200W，次级输出电压AC22V*24A。
调试方法：本机一般来说无需调整，装机后测中点电压在+-50mV内可以认为正常，否则可调整R2的阻值，如偏离电压高则加大R2，反之则减小。
简单音频功放电路原理图（二）文中介绍的是一款由NE5532构成的OCL准互补功放电路。
该音频功率放大电路采用一运算放大器组成驱动级，晶体三极管VT1~VT4组成复合式互补对称电路，担任功率放大。
电路总增益Au=（R1+R3）/R1，RL为扬声器。
交流信号的工作过程与简单的互补对称功率放大器类似。
其中电位器RP1调节整机的增益，RP2用于调整中点电压。
本电路经过简单的调试即可成功，更换不同的运放整机的音色都会随之改变，DIY的乐趣尽在其中。
缺点是功率较小，可以把运放的供电提高并稳压在正负15V，后级功放管的电压提高到正负30V以上，即可满足一般家庭使用的需要。
简单音频功放电路原理图（三）LM4889是一款主要应用于手机的音频功率放大器。
5V电源时，它能够提供1瓦的连续平均功率输出（8Ω桥式连接负载），失真小于2%（THD+N）。
LM4889需要的外部元件极少，不需要输出耦合电容器或启动电容器，因此适合移动电话和其他低电压应用。
该LM4889具有低功耗的停机模式、内部误关断保护机制、噪音消除功能，可以配置外部的增益设定电阻。
LM4889典型应用电路：简单音频功放电路原理图（四）LM380集成音频功率放大器的应用电路如下图所示：简单音频功放电路原理图（五）OPA541芯片是一个功率放大器，它能由最大为士40V的电源供电，而产生最大电流为5A的连续输出。
音频功放电路原理图讲解
音频功放电路原理图讲解音频功放电路原理图讲解功放，顾名思义，就是功率放大的缩写。
与电压或者电流放大来说，功放要求获得一定的、不失真的功率，一般在大信号状态下工作，因此，功放电路一般包含电压放大或者电流放大电路没有的特殊问题，具体表现在:①输出功率尽可能大;②通常在大信号状态下工作;③非线性失真突出;④提高效率是重要的关注点;⑤功率器件的安全问题。
而对于音频功放电路，也需要注意以上的问题。
根据放大电路的导电方式不同，音频功放电路按照模拟和数字两种类型进行分类，模拟音频功放通常有A类，B类，AB类， G类，H 类 TD功放，数字电路功放分为D类，T类。
下文对以上的功放电路做详细的介绍和分析。
1. A类功放(又称甲类功放)A类功放如上图所示，在信号的整个周期内都不会出现电流截止(即停止输出)的一类放大器。
但是A类放大器工作时会产生高热，效率很低。
尽管A类功放有以上的弊端，但固有的优点是不存在交越失真，并且内部原理存在着一些先天优势，是重播音乐的理想选择，它能提供非常平滑的音质，音色圆润温暖，高频透明开扬，中频饱满通透的优点。
单端放大器都是甲类工作方式，推挽放大器可以是甲类，也可以是乙类或甲乙类。
2.B类功放(又称乙类功放)B类功放是指正弦信号的正负两个半周分别由推挽输出级的两个晶体管轮流放大输出的一类放大器，每一晶体管的导电时间为信号的半个周期，通常会产生我们所说的交越失真。
通过模拟电路的调整可以将该失真尽量的减小甚至消失。
B类放大器的效率明显高于A类功放。
3.AB类功放(又称甲乙类)AB类功放界于甲类和乙类之间，推挽放大的每一个晶体管导通时间大于信号的半个周期而小于一个周期。
因此AB类功放有效解决了乙类放大器的交越失真问题，效率又比甲类放大器高，因此获得了极为广泛的应用。
4.D类功放(又称丁类功放)D类功放也称数字式放大器，利用极高频率的转换开关电路来放大音频信号，具体工作原理如下：D类功放采用异步调制的方式，在音频信号周期发生变化时，高频载波信号仍然保持不变，因此，在音频频率比较低的时候，PWM的载波个数仍然较高，因此对抑制高频载波和减少失真非常有利，而载波的变频带原理音频信号频率，因此也不存在与基波之间的相互干扰问题。
音响入门：前级、后级，前级功放、前置放大器都是什么？
音响入门：前级、后级，前级功放、前置放大器都是什么？HIFI秀全时的HIFI秀场 HIFI文化的交流平台什么是前级功放、后级功放、合并式放大器？它们之间有什么联系、区别？功放一般分为前级功放、后级功放与合并式功放（俗称合并机）。
前级是用来把信号作初步放大、调节音量的；而后级则是把前级来的信号作大量放大来推动扬声器。
合并机就是把前级、后级集于一身的机器。
功放：功放的工作原理就是将音源播放的各种声音信号进行放大，以推动音箱发出声音。
从技术角度看，功放好比一台电流的调制器，它将交流电转变对直流电，然后受音源播放的声音信号控制，将不同大小的电流，按照不同的频率传输给音箱，这样音箱就发同相应大小、相应频率的声音了。
由于考虑功率、阻抗、失真、动态以及不同的使用范围和控制调节功能，不同的功放在内部的信号处理、线路设计和生产工艺上也各不相同。
前级功放：前级功放的专业叫法是：前置放大器。
也是整套器材中对音色影响最大的部分，它是提供合适的音频电平信号，调节音质的器材（俗称前置放大器，接在音源和功率放大器之间）。
前级可分为有源及无源两种。
有源的前级，是使用电源把信号放大。
无源的前级，就只有调节音量的功效。
老实讲，现今成功的无源前级不多，因为音源与后级的内阻有很大分别，只靠一个音量开关把音源与后级连接起来，内阻的差别会使动态、细节、频应尽失！有源的前级除了调节音量外，还可作初部广大及降低音源及后级间内阻之别，即用作缓冲。
后级功放：后级功放的专业叫法是：纯后级功放。
这才是真正的功放部分，它对动态和低频控制力方面影响大。
是单纯地把”前级“音频信号进行放大，以提供足够的功率驱动音箱喇叭发声的器材(总是接在音箱之前)。
后级是把从前级来的信号放大给杨声器用的，后级必须够力去推动扬声器。
所谓够力，不是指越大声越够力。
必须有能力去支持整个乐团的大场面而不失其细节。
为什么需要功放？功放不仅仅是做功率输出那么简单，对于 Hi-Fi 来说，它需要对基础的声音进行解析处理，尽可能地还原声音效果，之后再进行放大，让音箱发出声音，保证音质细节的输出，而对于家庭影院来说，那就更实在了，它可以做到音视频信号分离，之后进行解码和画质音质的增强处理，最后输出至电视/投影仪和音箱，已达到更完美的效果。
功率放大器原理及电路图PPT课件
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1 高频功率放大器的动态特性
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功率放大器按工作状态分类：
A（甲）类：导通角为 180o
功率放大器的基本结构和工作原理
功率放大器的基本结构和工作原理功率放大器的基本结构和工作原理功率放大器的基本结构和工作原理扩音机是一种对声音信号进行放大的电子设备，其基本结构如图5-1所示，常分为前置放大器(简称前级)和功率放大器(简称后级)两大部分。
前置放大器通常由输人选择与均衡放大电路、等响音量控制电路、音调控制电路等组成，而功率放大器常由功率放大电路和扬声器保护电路组成。
扩音机工作时，输人选择电路主要对收音调谐器、录音座、CD唱机和Av辅助输入等信号源的信号进行选择切换控制，得出所需的信号输入，输入后的信号经均衡放大电路进行频率特性的校正和放大，使输入信号的频率特性变得较为平坦，同时使各种信号源输入的信号电平基本趋于一致，避免在转换不同的信号源时，声音响度出现较大的变化，影响使用效果。
均衡放大后的信号则由等响音量控制电路控制信号的强弱，从而调节音量的大小。
等响控制的目的主要是在音量较小时提升高、低频信号成分，以补偿人耳听觉的不足，在低响度时得到较丰满的声音信号。
而音调控制电路则主要是根据个人的喜好调节电路的频率特性，适当提升或衰减声音中的高、低频成分，以满足听音者的需求。
经前置放大器放大处理后的信号被送人功率放大器进行功率放大，以推动扬声器重放出声音。
扩音机中为了保护扬声器免受电路冲击电流的干扰，或在电路出现故障时烧毁扬声器，常在功率放大器中加入扬声器保护电路。
在高保真的音响设备中，扩音机常有两种组合结构形式，一种是把前置放大器和功率放大器组合在一起，称作合并式扩音机，这种形式把“前置”和“功放”合并在一起，这时由于小信号电压放大的前置级和大信号电流放大的功率放大在电性能上不能互相兼顾，因而不能使扩音机达到最佳的工作状态，特别是前、后级的电源馈电，电源变压器的电磁干扰，印制电路板的走线排列，共用地线的走向等方面总会存在一定的相互干扰，影响整机性能的提高。
另一形式是在设计制造上把前置放大器和功率放大器彻底分开，分别使用独立电源，单独的机壳，使前、后级之间互不干扰，形成前、后级分体式的结构，在使用时再把它们用信号传输线连接起来，这种分体式结构的扩音机可获得极高的性能指标。
功率放大器电路图及其原理
一、O PA300放大电路OPA300放大电路功能说明：通过设定电阻R4=3R3 来设定该放大器的放大倍数为四倍，即Vout=(1+Rf / R) Vin ，将VCA810的输出信号放大到能满足检波需要的信号。
二、高栅负压的电子管功放电路图下图中R3既是前级的直流负载电阻。
又是给后级提供栅负压的偏值电阻。
它适用于栅负压较高的功率管制作的功放电路。
电路比较简单。
电路中两个竹子的灯丝接地端。
应接在各自阴极电阻的下端。
同样要求电源变压器有两个灯丝绕组，功率级与前级的灯丝分别供电。
电路是用6Pl做的实验，虽然栅负压较低，但工作很正常，说明电路是成功的。
同样要注意的是：一定要在插上前级管子后再开电源，否则不能加电。
三、推挽式功率放大级的正偏压电路此电路用EL34管。
在两只功放管阴极电路中串入一只50Ω左右的线绕电位器或半可变线绕电阻，中点接地即可。
调整电位器W使两管的阴极电压平衡、对称，再放音就会有出色的表现。
正偏压的方式也可以用在ABI类自给偏压的推挽式功率放大级中。
四、AD8656双运放芯片组成的接收放大电路使用AD8656双运放芯片组成接收放大电路。
该运放适合+2.7～+5.5 V电源电压供电，是具有低噪声性能的精密双运算放大器。
AD8656型CMOS放大器在满共模电压(VCM)范围内提供250 mV精密失调电压最大值，且在10 kHz处提供低电压噪声谱密度和0.008%的低真，无需外部三极管增益级或多个并行的放大器以减小系统噪声。
通过干电池提供3V单电源供电，接收放大电路如图2所示。
放大电路由AD8656进行两级放大，抵消线圈所感应到的信号电压幅值因距离的增加而产生的衰减，放大所接收到的微弱信号，增加无线传输距离。
系统接收电路经D8656放大后的输出电压输至单片机进行A/D转换，对数据进行编解码，而未采用检波解调电路，可有效简化电路结构。
五、高频信号放大电路的性能比较分析一、高频管(UHF)9018fTl00(MHz)的信号放大电路电视高频头输出的第一中频信号和音频信号通过高频管9018放大后也确有显效。
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1
8
7
6
5
4
3
2
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R8 VCC+ D1 1N4148 Q1 2N5401 R3 R2 330K 10K 2N5551 C1 100/35V Q2 MPSA75 Q3 R36 C2 47/35V D3 1N4148 D2 1N4148 D13 R32 1.5K/1% R31 3.3K 4.7K R10 100K R4 VCC22K R5 4.7K TURN ON DELAY R7 10K R11 22K 1 2 3 4 5 6 7 8 IC4 NE5517AN 16 15 14 13 12 11 10 9 R37 47K C16 470uF C14 470uF R6 10K 10K R9 1K R34 499/1% R35 750/1% Z1 VCC+ 1N5353
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R1 5.6K/1W
IC1 LM317
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R14 150/0.5W
R7 4.7K
各类功放原理图及原理介绍
各类功放原理图及原理介绍各类功放原理图及原理介绍在音响领域里人们一直坚守着A类功放的阵地。
认为A类功放声音最为清新透明，具有很高的保真度。
但是，A类功放的低效率和高损耗却是它无法克服的先天顽疾。
B类功放虽然效率提高很多，但实际效率仅为50%左右，在小型便携式音响设备如汽车功放、笔记本电脑音频系统和专业超大功率功放场合，仍感效率偏低不能令人满意。
所以，效率极高的D类功放，因其符合绿色革命的潮流正受着各方面的重视。
由于集成电路技术的发展，原来用分立元件制作的很复杂的调制电路，现在无论在技术上还是在价格上均已不成问题。
而且近年来数字音响技术的发展，人们发现D类功放与数字音响有很多相通之处，进一步显示出D类功放的发展优势。
D类功放是放大元件处于开关工作状态的一种放大模式。
无信号输入时放大器处于截止状态，不耗电。
工作时，靠输入信号让晶体管进入饱和状态，晶体管相当于一个接通的开关，把电源与负载直接接通。
理想晶体管因为没有饱和压降而不耗电，实际上晶体管总会有很小的饱和压降而消耗部分电能。
这种耗电只与管子的特性有关，而与信号输出的大小无关，所以特别有利于超大功率的场合。
在理想情况下，D类功放的效率为100%，B类功放的效率为78.5%，A类功放的效率才50%或25%（按负载方式而定）。
D类功放实际上只具有开关功能，早期仅用于继电器和电机等执行元件的开关控制电路中。
然而，开关功能（也就是产生数字信号的功能）随着数字音频技术研究的不断深入，用与Hi-Fi音频放大的道路却日益畅通。
20世纪60年代，设计人员开始研究D类功放用于音频的放大技术，70年代Bose公司就开始生产D类汽车功放。
一方面汽车用蓄电池供电需要更高的效率，另一方面空间小无法放入有大散热板结构的功放，两者都希望有D类这样高效的放大器来放大音频信号。
其中关键的一步就是对音频信号的调制。
图1是D类功放的基本结构，可分为三个部分：图1 D类功放基本结构第一部分为调制器，最简单的只需用一只运放构成比较器即可完成。
高峰功放原理图125381
©2005 by Crown Audio , Inc., 1718 W. Mishawaka Rd., Elkhart, Indiana 46517-9439 U.S.A. Telephone: 574-294-8000
®
125381-6 10/05
CP660 Power Amplifier
Important Safety Instructions
FCC COMPLIANCE NOTICE
This device complies with part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. CAUTION: Changes or modifications not expressly approved by the party responsible for complicance could void the user’s authority to operate the euqipment. NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
高峰功放电路图101229
Models:Power Base-1, 2 & 3© 1996 by Crown International, Inc., P.O. Box 1000, Elkhart, Indiana46515-1000 U.S.A. Telephone: 219-294-8000. Power-Tech amplifiersare produced by the Professional Audio Division of CrownInternational, Inc. Trademark Notice: Power Base-3™ is a trademarkand Power Base-1®, Power Base-2®, Crown,®IOC® and ODEP® areregistered trademarks of Crown International, Inc. Other trademarksare the property of their respective owners.®E106377Applies only to 120 VAC,North American PB-1,PB-2 and PB-3 units.101229-112/96Applies only to 120 VAC,North American PB-1and PB-2 units.®LL 32521CThe lightning bolt triangle is used to alert the user to the risk of electric shock.The exclamation pointtriangle is used to alert the user to important operatingor maintenance instructions.The information furnished in this manual does not include all of the details of design, production, or variations of the equipment. Nor does it cover every possible situation which may arise during installation, operation or mainte-nance. If you need special assistance beyond the scope of this manual, please contact our T echnical Support Group.Crown Audio Division Technical Support GroupPlant 2 SW, 1718 W. Mishawaka Rd., Elkhart, Indiana 46517 U.S.A.Phone: 800-342-6939 (North America, Puerto Rico and Virgin Islands) or 219-294-8200Fax: 219-294-8301 Fax Back: 800-294-4094 (North America only) or 219-293-9200Internet: Power Base Series Power AmplifiersPage 41Welcome 71.1Unpacking 71.2Features 72Installation 92.1Stereo 92.2Mono 92.3102.4.......................................102.5103Operation 113.1113.2113.3113.3.1ODEP 113.3.2113.3.3Drive Protection 113.3.4.....................123.3.5123.4Controls 123.5124135Accessories 195.1195.2MT-BB 196Service 206.1Worldwide Service 206.2206.2.1206.2.220Power Base Series Power AmplifiersPage 51.17.......................................892.3Power Base Input Wiring 92.4Input Sensitivity Switch 1010121516161718185.1The MT-XLR 1919Power Base Series Power AmplifiersPage 7Power Base ODEP ®)MT-BB ac-Power PowerPower Base Series Power AmplifiersPage 8Power Base Series Power AmplifiersPage 92 InstallationAlways remove power from the unit and turn the level controls off (fully counterclockwise) when making or breaking connections. This reduces the chance of blasts that can cause loudspeaker damage.The guidelines below are provided to help you quickly get your amplifier installed and ready to go. Be sure to follow the instructions in Sections 2.1 and 2.2 for the selected mode of operation. Additional information on input sensitivity, load protection and required AC mains is provided in Sections 2.3, 2.4 and 2.5.1.Install the amplifier in a standard 19 inch (48.3 cm) rack or place it on a stable surface. The mounting dimensions are 19 inches (48.3 cm) wide, 3.5 inches (8.9 cm) tall and 16 inches (40.6 cm) deep behind the mounting sur-face. IMPORTANT! Allow for adequate ventilation.2.1 Stereo1.Turn down the level controls (fully counterclockwise) and turn off the amplifier.2.Set the back panel stereo/mono switch to Stereo.3.If present, remove the Parallel-Mono jumper.4.Connect the input and output cables as shown in the first example in Figure 2.1.5.Turn on the amplifier and adjust the level for each chan-nel using the back panel level controls.CAUTION: Never parallel the two outputs by di-rectly tying them together, and never parallel them with the output of another amplifier.2.2 MonoYour amplifier’s mono modes provide double the power of Stereo mode in a single channel. In Bridge-Mono mode, the outputs are wired in series for twice the output voltage. In Parallel-Mono mode, the outputs are paralleled for twice the current capacity.Bridge-Mono mode is provided for loads with an im-pedance greater than 4 ohms. Parallel-Mono mode should be used with loads of 4 ohms or less.B R I D G E - M O N O1.Turn down the level controls (fully counterclockwise) and turn off the amplifier.2.Set the back panel stereo/mono switch to Bridge-Mono.3.If present, remove the Parallel-Mono jumper.4.Connect the input and output cables as shown in the sec-ond example in Figure 2.1. Only use the channel 1 input.5.Make sure the load is balanced (neither side shorted to ground) and do not use the black (–) binding posts.6.Turn on the amplifier and adjust the level. Only use thechannel 1 level control.P A R A L L E L - M O N O1.Turn down the level controls (fully counterclockwise) and turn off the amplifier.2.Set the back panel stereo/mono switch to Parallel-Mono.3.Install a solid, 14-gauge (2 mm 2) or heavier jumper wire across the two red (+) binding post outputs.4.Connect the input and output cables as shown in the third example in Figure 2.1. Only use the channel 1 input.5.Turn on the amplifier and adjust the level. Only use the channel 1 level control.CAUTION: With Parallel-Mono wiring, do not switch to Stereo or Bridge-Mono mode until the output jumper wire is removed.AIR FLOWFig. 2.3 Power Base Input Wiringe high-quality loudspeaker cables to connect the load to the amplifier’s outputs. Do not use shielded cable.e shielded cables to connect audio sources to the amplifier inputs. Either balanced or unbalanced wiring can be used as shown below. (XLR connectors are avail-able with the MT-XLR accessory. See Section 5.)Fig. 2.2 Do NOT Block Air FlowPower Base Series Power AmplifiersPage 10Page 113.3.1 ODEPCrown invented ODEP to keep the amplifier working under demanding conditions and to increase output efficiency. To do this, Crown established a rigorous pro-gram to measure each transistor’s safe operating area (SOA). Intelligent circuitry was then designed to simu-late the instantaneous conditions of the output transis-tors. Its name describes what it does: Output Device Emulation Protection, or ODEP . In simple terms, ODEP compares transistor conditions to their known SOA. If more power will be asked of them than they can deliver under the existing conditions, ODEP limits the drive until conditions fall within the SOA. Limiting is propor-tional and kept to an absolute minimum—only what is required to prevent output transistor damage. Under normal conditions, no limiting is required and ODEP is transparent to the audio signal.ODEP makes possible a quantum leap in output effi-ciency and reliability—with ODEP , the show goes on.3.3.2 Ultrasonic and Radio Frequency ProtectionAn amplifier’s slew rate only needs to be large enough to deliver the maximum voltage at the highest required frequency. Higher slew rates actually allow undesirable ultrasonic and radio frequencies to be reproduced. By design, Power Base amplifiers have a controlled slew rate to limit the highest frequencies that they reproduce.Limiting occurs well above 20 kHz so there is no au-dible effect on performance. This approach protects the amplifier from radio frequencies and can even pro-tect some sensitive loads (including some tweeters).3.3.3 Drive ProtectionThe drive protection system temporarily removes output drive to protect the amplifier and its loads. Drive protec-tion can be activated in two situations. First, if dangerous subsonic frequencies or direct current (DC) is detected in the amplifier’s output, the unit will activate its DC/low-frequency protection circuitry which puts the amplifier in drive protection mode. This protects the loads and pre-vents oscillations. The unit resumes normal operation as soon as the amplifier no longer detects dangerous out-put. Although it is extremely unlikely that you will ever activate the amplifier’s DC/low frequency protection system, improper source materials like subsonic square waves or input overloads that excessively clip the input signal can activate this system.The amplifier’s fault protection system will put the am-plifier in drive protection mode in rare situations whereheavy common-mode current is detected in the output.3 Operation3.1 PrecautionsAlthough your amplifier is protected from external faults,the following safety precautions are recommended:1.There are important differences among the Stereo,Bridge-Mono and Parallel-Mono operating modes.Please refer to Sections 2 for additional information.2.WARNI NG: Do not change the position of the stereo/mono switch unless the amplifier is first turned off.3.CAUTI ON: I n Parallel-Mono mode, a jumper is used to connect the red binding post outputs.Be sure to remove this jumper for Bridge-Mono or Stereo mode, or high distortion and excessive heating will occur. Also, make sure the stereo/mono switch is set to the proper e care when making connections, selecting sig-nal sources and controlling the output level. The load you save may be your own!5.Do not short the ground lead of an output cable to the input signal ground. This will form a ground loop and may cause oscillations.6.Operate the amplifier from AC mains of not more than 10% variation above or below the selected line voltage and only at the specified line frequency.7.Never connect the output to a power supply out-put, battery or power main. Such connections may result in electrical shock.8.Tampering with the circuitry by unqualified person-nel or making unauthorized circuit changes may be hazardous and invalidates all agency listings.Remember: Crown is not liable for any damage that re-sults from overdriving other system components.3.2 Power IndicatorWhen lit, the amber power indicator (to the left of the power switch) shows that the amplifier has been turned on. It is driven only by the low-voltage power supply and does not indicate the status of the high-voltage supplies.3.3 Protection SystemsPower Base amplifiers have extensive protection sys-tems, including ODEP , ultrasonic/RF protection, drive protection, transformer thermal protection and fuses or circuit breakers that protect the power supplies.The unit should never output heavy common-mode cur-rent unless its circuitry is damaged. Activating drive protection helps prevent further damage.3.3.4 Transformer Thermal ProtectionAll Power Base amplifiers have transformer thermal protection. This protection circuitry is activated in un-usual situations where the unit’s transformer tempera-ture rises to unsafe levels. Under these abnormal conditions, the unit removes power to the high-voltage transformer. The fan will continue to run in all units ex-cept those with 220/240 VAC transformers. The ampli-fier will return to normal after it cools to a safe temperature.It is very unlikely that your Power Base amplifier will ever activate transformer thermal protection as long as it is operated within rated conditions. Your amplifier is designed to continue operating under conditions where other amplifiers would fail. But even when you exceed the limits of a Power Base amplifier, it still pro-tects itself—and your investment—from damage.3.3.5 Fuses and Circuit BreakersAll 120 VAC, 60 Hz units and all Power Base-3 units have a fuse that protects the low-voltage power supply and cooling fan. The Power Base-1 and Power Base-2 high-voltage power supplies are protected by fuses, while the Power Base-3 high-voltage power supplies are protected by a circuit breaker. With rated loads and output levels, these fuses (or the circuit breaker) should only shut down the amplifier in the incredibly rare instance of a catastrophic amplifier failure. The ODEP protection system keeps the amplifier opera-tional under most other severe conditions. The fuses (or breaker) can also shut down the amplifier in situa-tions where extremely low-impedance loads and high output levels result in excessive current draw.A Power Base amplifier will not blow its fuses or trip its breaker unless something is wrong. In the rare event that an internal fuse blows, please refer the unit to a qualified technician. If the breaker in a Power Base-3 trips, try to identify and correct the problem before re-setting it with the back panel Circuit Breaker Reset. If the problem persists, refer the unit to a qualified techni-cian.3.4 ControlsThe Power switch is th only control located on the front panel. All others are located on the rear, including the level controls.When making any setup or wiring changes, don’t forget to turn off the amplifier, turn down the level controls and disconnect the power cord. Be sure to turn down (full counterclockwise) the channel 2 level control when us-ing either mono mode. The Parallell Mono/Stereo/ Bridge Mono switch is used to select Stereo, Bridge-Mono or Parallel-Mono operating modes. The Input Ground Lift switch isolates the phone jack input grounds from the chassis ground to help prevent ground loops. It does not affect any installed input ac-cessories. The Input Sensitivity Switch, located inside the back cover plate, sets the amplifier’s input sensitiv-ity (refer to subsection 2.3 for information on changing this switch). And the Power Base-3 has a back panel Circuit Breaker Reset button that resets the circuit breaker (refer to subsection 3.3.5).CHANNEL 2CHANNEL 13.5 Filter CleaningA dust filter is provided on the unit’s air intake. If it be-comes clogged, the unit will cool less efficiently and may produce lower output levels. To clean the filter, use a phillips screwdriver to remove the three screws the secure the front grille. Use mild dishwashing deter-gent and warm water for best cleaning results. Be sure the filter is dry before you reinstall it. Replacement fil-ters may be ordered from the factory.Dust filters are not 100% efficient—long term this may require internal heat-sink cleaning by a qualified tech-nician. Internal cleaning information is available from our Technical Support Group.Fig. 3.1 Back Panel Level ControlsPage 124 Specificationsand an input sensitivity of 26 dB unless otherwise specified. Standard 1 kHz Power:watts at 1 kHz with 0.1% THD+noise.Full Bandwidth Power:watts from 20 Hz to 20 kHz with 0.1% THD+noise.120 VAC, 60 Hz Units:formers for 120 VAC, 60 Hz power mains.PerformanceFrequency Response:at 1 watt.Phase Response:at 1 watt.Signal-to-Noise:bandwidth power from 20 Hz to 20 kHz.Total Harmonic Distortion (THD):ing linearly to 0.1% at 20 kHz.Intermodulation Distortion (IMD):bandwidth power.Damping Factor:CrosstalkPower Base-1: Greater than 75 dB below full band-greater than 60 dB at 20 kHz.Power Base-2: Greater than 90 dB below full band-greater than 66 dB at 20 kHz.Power Base-3: Greater than 90 dB below full band-greater than 70 dB at 20 kHz.Common Mode Rejection (CMR):falling linearly to better than 50 dB at 20 kHz.Controlled Slew Rate: Greater than 13 volts/ms.Voltage Gain:dB position).Power Base-1: 51:1 ±12% or 34.3 dB ±1 dB at 0.775 sensitivity.Power Base-2: 64:1 ±12% or 36.2 dB ±1 dB at 0.775 volt sensitivity; 35:1 ±12% or 31.0 dB ±1 dB at 1.4 volt sensitivity.Power Base-3: 83:1 ±12% or 38.4 dB ±1 dB at 0.775 volt sensitivity; 46:1 ±12% or 33.3 dB ±1 dB at 1.4 volt sensitivity.The following specifications are guaran-Power Base-1Stereo mode (both channels driven):240watts into 4 ohms.200watts into 8 ohms.Bridge-Mono mode:455watts into 8 ohms.395watts into 16 ohms.Parallel-Mono mode:455watts into 2 ohms.400watts into 4 ohms.Power Base-2Stereo mode (both channels driven):460watts into 4 ohms.325watts into 8 ohms.Bridge-Mono mode:910watts into 8 ohms.660watts into 16 ohms.Parallel-Mono mode:920watts into 2 ohms.655watts into 4 ohms.Power Base-3Stereo mode (both channels driven):760watts into 4 ohms.540watts into 8 ohms.Bridge-Mono mode:1525watts into 8 ohms.1090watts into 16 ohms.Parallel-Mono mode:1530watts into 2 ohms.1080watts into 4 ohms.Safe with all types of loads. RatedPage 13Required AC Mains: Current, frequency and voltage requirements are provided on each unit’s back panel. All models draw 90 watts or less at idle.Power Base-1: Draws up to 6 amps of current.Power Base-2: Draws up to 10 amps of current.Power Base-3: Draws up to 15 amps of current.Low-Voltage Power Supply: A ±24 VDC fanformer supply (fan motor winding) regulated to ±15 VDC.AC Connector: An appropriate AC line cord and plug are provided. 120 VAC, 60 Hz units have a standard 3-wire, 15-amp grounded connector (NEMA 5-15P). ControlsPower: A front panel rocker switch used to turn the amplifier on and off.Level: A back panel rotary potentiometer for each chan-nel used to control the output level.Stereo/Mono: A three-position back panel switch used to select Stereo, Bridge-Mono or Parallel-Mono mode.Sensitivity: A three-position switch inside the back cover plate used to select the input sensitivity for both channels: 0.775 volts or 1.4 volts for standard 1 kHz power, or 26 dB voltage gain (see Section 2.3).Input Ground Lift: A two-position back panel switch used to isolate the phone jack and chassis grounds. Reset (Power Base-3 only): A back panel push but-ton used to reset the circuit breaker that protects the power supplies.IndicatorsPower: This amber indicator shows the on/off status of the low voltage power supply.Input/OutputInput Connector: Balanced ¼ inch phone jacks. See Section 5 for XLR and barrier block accessories.I nput I mpedance: Nominally 20 K ohms, balanced;10 K ohms, unbalanced.Output C onnector:T wo s ets o f c olor-coded 5-way b binding posts (for banana plugs, spade lugs or bare wire). Output Impedance: Less than 10 milliohms in series with less than 2 microhenries.DC Output Offset:Less than 10 millivolts.Output SignalStereo: Unbalanced, two-channel.Bridge-Mono: Balanced, single-channel. Channel 1 controls are active; Channel 2 controls should be turned down and not used.Parallel-Mono: Unbalanced, single-channel. Channel 1 controls are active; Channel 2 controls should be turned down and not used.ProtectionPower Base amplifiers are protected against shorted, open or mismatched loads; overloaded power supplies; excessive temperature, chain destruction phenomena, input overload and high-frequency blowups. They also protect loudspeakers from input and output DC, as well as providing protection from turn-on/turn-off transients.If operating conditions are unreasonable, the patented ODEP circuitry proportionally limits the drive level to pro-tect the output transistors, particularly in the case of el-evated temperature. A thermal switch imbedded in the transformer protects the power supplies from overload. In the rare event that a transformer overheats, the ther-mal switch removes power, waits until the unit has cooled to a safe temperature and then resets itself.Turn On: Four second delay with no dangerous tran-sients. Contact us if you need to change the delay. ConstructionDurable black finish on steel chassis with special “flow-through” ventilation from front to side panels.Cooling: Internal heat sinks with forced-air cooling for rapid, uniform heat dissipation.Dimensions: Standard 19-inch (48.3 cm) rack mount width (EIA RS-310-B), 3.5-inch (8.9 cm) height and 16-inch (40.6 cm) depth behind the mounting surface. Approximate Weight: Center of gravity is 6 inches (15.2 cm) behind front mounting surface.120 VAC, 60 Hz Units:Power Base-1: 30 pounds (13.6 kg) net; 34 pounds(15.4 kg) shipping weight.Power Base-2: 34 pounds (15.4 kg) net; 38 pounds(17.2 kg) shipping weight.Power Base-3: 36 pounds (16.3 kg) net; 40 pounds(18.2 kg) shipping weight.Page 14” Each ofguaranteed to meet or exceed their specifications for three years. Further, because our published specs are set below our “in-house” measurements, you can expect everyPage 15Page 16Page 17Page 185 AccessoriesThere are two accessories available at the time of this printing: the MT-XLR and the MT-BB. Important: The MT-XLR and MT-BB must be installed at a Crown Factory Service Center or the Crown factory.5.1 MT-XLRThe MT-XLR is an accessory panel that provides two standard 3-pin female XLR input connectors. The MT-XLR accessory makes it easy to quickly change connections in a system that uses standard XLR con-nectors. It can also be used in systems that need to daisy chain an input signal from one amplifier to an-other. Because the MT-XLR connectors are wired in parallel with the amplifier’s built in phone jack connec-tors, an input signal fed to either input can be fed to another amplifier from the unused connector for that channel.5.2 MT-BBThe MT-BB is an accessory panel that provides barrier strip input connectors. An MT-BB accessory might be desirable in applications requiring bare wire connec-tions. It can also be used to daisy chain an input signal from one amplifier to another just like the MT-XLR.Fig. 5.1 The MT-XLRFig. 5.2 The MT-BBPage 196 ServiceThis unit has very sophisticated circuitry which should only be serviced by a fully trained technician. This is one reason why each unit bears the following label: CAUTI ON: To prevent electric shock, do not re-move covers. No user serviceable parts inside. Re-fer servicing to a qualified technician.6.1 Worldwide ServiceService may be obtained from an authorized service center. (Contact your local Crown/Amcron representa-tive or our office for a list of authorized service centers.) To obtain service, simply present the bill of sale as proof of purchase along with the defective unit to an authorized service center. They will handle the neces-sary paperwork and repair.Remember to transport your unit in the original factory pack. We will pay the surface shipping costs both ways for warranty service to the authorized service center nearest you after receiving copies of all ship-ping receipts. You must bear the expense of all taxes, duties, and customs fees when transporting the unit.6.2 North American ServiceService may be obtained in one of two ways: from an authorized service center or from the factory. You may choose either. It is important that you have your copy of the bill of sale as your proof of purchase.6.2.1 Service at a North American Service CenterThis method usually saves the most time and effort. Simply present your bill of sale along with the defective unit to an authorized service center to obtain service. They will handle the necessary paperwork and repair. Remember to transport the unit in the original factory pack. A list of authorized service centers in your area can be obtained from our Technical Support Group. 6.2.2 Factory ServiceTo obtain factory service, fill out the service informa-tion page that follows and send it along with your proof of purchase and the defective unit to the Crown factory. For warranty service, we will pay for ground shipping both ways in the United States after receiving copies of the shipping receipts. Shipments should be sent “UPS ground.” (If the unit is under warranty, you may send it C.O.D. for the cost of freight via UPS ground.) The fac-1.When sending a Crown product to the factory forservice, be sure to fill out the service informationform that follows and enclose it inside your unit’sshipping pack. Do not send the service informa-tion form separately.2.T o ensure the safe transportation of your unit tothe factory, ship it in an original factory packingcontainer. If you don’t have one, call or writeCrown’s Parts Department. With the exception ofpolyurethane or wooden crates, any other pack-ing material will not be sufficient to withstand thestress of shipping. Do not use loose, small sizepacking materials.3.Do not ship the unit in any kind of cabinet (woodor metal). Ignoring this warning may result in ex-tensive damage to the unit and the cabinet. Ac-cessories are not needed—do not send theinstruction manual, cables and other hardware.Always use theoriginal factory packto transport the unit. Crown Audio DivisionT echnical Support / Factory ServicePlant 2 SW, 1718 W. Mishawaka Rd., Elkhart,Indiana 46517 U.S.A.T elephone:219-294-8200800-342-6939 (North America,Puerto Rico, and Virgin Islands only)Facsimile:219-294-8301 (Technical Support)219-294-8124 (Factory Service)Fax Back:219-293-9200800-294-4094 (North America only) Internet:Page 20。
专业功放电路图1
专业功放电路图1QSC MX-1500 功放>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>NUSUN CE-060 定压输出功放>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>SPIRIT AV-600 功放声艺VA-600功放是一款较为高档的专业功放，下图是根据实物绘制的主功放电路图，其电路结构与传统OCL功放有较大的区别，特别是采用具有电源补偿功能的双电源供电结构，能有效降低功耗和温升，克服强信号时的动态失真，很多国外名牌专业功放也都采用了类似电路。
Q1、Q2组成NPN差分放大器，Q3、Q4构成镜流源。
Q6、Q7组成PNP差分放大器，Q8、Q9是镜流源。
ZD1、ZD2与C5、C6、R7、R14组成+36V稳压器，既给镜流源提供稳压偏置，又是两个差分放大器的发射极的稳压源。
R21、R22组成直流反馈网络，R19、C7、R20、c8组成高频补偿电路。
为了提高电压放大级Q11、Q12驱动电流，比普通功放增加了Q5、Q10缓冲放大级。
恒压偏置电路中Q13采用TIP42这种。
PNP管是此机的另一个特点。
环境温度引起Q11、Q12之间电流增加时，恒压偏置管集电极与发射极之间的压差Uce增大，此电压直接加在Q13的发射极。
加大Q13的偏置而增加导通。
从而达到降低Uce，使推动级Q14、Q15有一个恒定的偏置。
一般功放的恒压偏置管都采用NPN管，Uce 是通过上下偏置电阻分压后提供给偏置管基极，使其增加导通来稳定uce的。
一位烧友谈：为什么纯后级远强于合并机后级？兼谈功放前级的选取
一位烧友谈：为什么纯后级远强于合并机后级？兼谈功放前级的选取【参考阅读】为什么纯后级远强于合并机后级?兼谈功放前级的选取好多人在纠结着功放的搭配问题。
老丁也一直十分顽固的明确，万元以下的合并式功放其后级部分不值得考虑，特别是今年新出的合并式功放，后级严重缩水，乃至扩大到所有的合并式功放，其打击面何其之大呀，简直是口吐狂言！！好多人呆在199惯了，看问题先要辨别一下不是不枪手。
同时对老丁肯定有了1种看法：枪手，绝对的枪手，老秦的不折不扣的枪手！只不过不好意思明确而已。
其实，我对这个问题的看法也是近几个月泡坛子后深入调查研究后得出的，也是有1个循序渐进的认识过程的。
对于老秦的功放，开始也不太相信的，也与老秦有过一番争议，可以翻翻老帖。
老丁玩电子早于40多年前，以前没有这种偷工减料，虚报功率之事。
近20年来脱离了电子界，一年前空下来了，才重蹈江湖，发现江湖已经今非昔比，面目全非了，到处充斥着商业欺骗。
最好的例子就是手上17年前的上万元的一台小旗舰功放，改成纯后级后，60W×3 22W×4，用HTPC D2，将老秦的七个大箱子推得有滋有味！阿妹、小李、小刘等曾经来亲自听过。
在没有低音炮的情况下，他们都感受过了强烈的沙发按摩，比我用8400厉害的多了，充分说明了，老功放的力道还是非常十足的。
我还写过一篇帖子，虽然四个环绕声道只有标称的22W，在播放变2在一分40秒时，照样在环绕箱的倒相孔吹出了一阵阵的清风！以上说明了我的功放完全能胜任目前的使用情况。
反观20年后的今天，在那么多音响论坛上，谈的最多的就是“推不动”，看看厂家动不动就100-200W×7的标称功率，还有推不动之说，让我一直郁闷，无法理解。
几个月来，一直苦心研究如今的日系功放，才有了重新的认识，写下了多篇揭秘功放的文章和林林总总的不少帖子，对如今日系功放的标称方法也进行了深入的剖析。
简单的讲，近几年日系中高级功放功率标称方法就相当于在一根2A流量的水管上接上来七个A流量的水龙头，当你打开任何1个龙头时都能保证有A流量的水出来，但是，如果同时打开七个龙头呢？2A/7=0.28A×7ch！这个还是06-08年产的中级机和高级机的测试方法，入门机呢？1A的管子接七个龙头！1A/7=0.14A×7ch！！再来看看今年的机器，将入门机的方法引伸到了中级机！我不再来分析厂家为什么要这样做了，口舌已经费了不少，只要上了一点年纪的人都应该知道，铜和铝在以前只是比铁贵一点，是不值钱的，普通人家到处都有铜器，而今天呢？功放的后级就是要大量的使用了铜和铝！再回过来看看我们可怜的相信日系功放的那么多初级烧友。