In public broadcasting, what is the principle with the power amplifier? What's the main difference?
Power amplifier classificationAccording to the different modes of the power amplifier in the power amplifier, it can be divided into class a power amplifier (also called class a), class B power amplifier (also called class B), class B power amplifier (also called class AB) and class power amplifier (also called D).Class a power amplifier means a class of amplifiers that do not produce current cutoff (i.e., stop output) during the entire cycle of the signal (plus or minus 2.5 weeks of the sine wave). Class a amplifiers generate high heat and low efficiency, but the inherent advantage is that there is no crossover distortion. Single ended amplifiers operate in class A, and push-pull amplifiers can be class A or class B or class B.Class B power amplifier is a class of amplifiers whose output time is half of the signal, which is amplified by two "arm" of push-pull output stage, plus or minus 2.5 weeks of sinusoidal signal. Class B amplifier has the advantage of high efficiency and the drawback is that crossover distortion will occur.The class B power amplifier is bounded between Class A and class B, and each arm of push-pull amplification is longer than the half cycle of the signal but less than one cycle. Class B amplification can effectively solve the cross distortion problem of class B amplifier, and the efficiency is higher than that of class a amplifier. Therefore, it has been widely used.Class amplifier also known as digital amplifier, the use of very high frequency switching circuit to amplify the audio signal, with high efficiency, small size advantages. Many power amplifiers up to 1000W are just as large in size as VHS video tape. This type of amplifier is not suitable for wide band amplifiers, but has many applications in active subwoofer.
According to the magnitude of amplifier output stage, the amplifier can be divided into single ended amplifier and push-pull amplifier.The output stage of a single ended amplifier consists of an amplifying element (or a plurality of elements but connected in parallel) to amplify the positive and negative 2.5 weeks of the signal. Single end amplification machines can only take class a work status.The output stage of a push-pull amplifier has two "arms" (two sets of amplifying elements). When an arm current increases, the other "arm" current decreases, and the two states change in turn. For load, it seems that a "arm" is pushing, a "arm" in the pull, together to complete the current output task. Although class a amplifiers may employ push-pull amplification, it is more common to use push-pull amplification to form a class B or class a amplifier.
Commonly known as "power amplifiers" whose function is to weak signal from the sound source or pre amplifier amplification, promote sound and. A sound sound system, power amplifier role can not be done.The power amplifier is the most basic equipment in the audio system. Its task is to amplify the weak electrical signals from the signal source (the professional audio system, from the mixer) to drive the speaker to make a sound.Power amplifier power amplifier, can be said to be one of the largest family of all kinds of audio equipment, its main function is to amplify the weak signal source equipment input, playback to generate enough current to drive the loudspeaker to sound. Considering the power, impedance, distortion, dynamic and different range of use and control adjustment function, different amplifiers have different signal processing, line design and production process.
