An amplifier converts the signals of low energy into high energy of the same type.
The pa amplifier is a part of subwoofer speaker system. A pa amplifier fully enhances the sound quality and helps to provide a better sound experience. Amplifiers specifications are, signal gain, efficiency and output power. The amplifier power output is always measured in watts.
The stereo pa amplifier can easily handle volume peaks and speaker efficiency. The pa amplifier is seen as the one that produces loud sounds. The pa amplifiers take the incoming electrical signal and magnify it to a level where it drives a loudspeaker. These are classified based on following several classes.
Class A amplifiers: These can be operated at full power and used for low distortion and detailed music reproduction.
Class B amplifiers: can be operated only in the presence of incoming signal and are more energy efficient than Class A. The output power of Class B is usually switched off and on, these amps are subject to higher levels of distortion than Class A.
Class A/B amplifiers: The third category and are called transistor or the solid-state amplifiers and combine best characteristics of Class A and B amplifiers.
Class D amplifiers: These pa amplifiers are fully on or off. Such type of amplifiers process the incoming analog signals into digital form, which consists of high-frequency pulse wide modulations (PWM).
These can theoretically operate at 100 percent efficiency and use far less power than the traditional linear amplifiers.
Out of these classes the majority of amplifiers at present are based on technology called Class-D which can offer higher power efficiency than Class-A or Class-AB technology based amplifiers.
Whenever one plans to buy pa amplifiers, it is advisable to seek proper professional help from sound technicians. The most important point to be kept in mind is to know whether the loudspeakers are compatible to amplifiers. The power input should be in control otherwise it might create too much of complications in the music systems.
When choosing it, its output wattage should be properly checked in.
The other important factor is the total harmonic distortion or THD. There is no such amplifier which is can give ideal amplified signal because there are error components which distort the signal to certain degree.
The other parameter to be looked upon is the signal-to-noise ratio. It signifies the amount of hum and noise the amplifier can add up to the audio signal.
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