A power amplifier is a special electronic device designed to convert a small electric signal from a source into a more powerful signal. Indeed, to control electro-acoustic transducers, for example, headphones or loudspeakers, you need a powerful source signal without distortion, and the source often can not imagine the desired signal power or distorts it with undesirable effects.
The power amplifier can be either an independent separate device with its own panel and control system, or be an internal element of some device and be soldered into a hybrid circuit. This device is the last link in any sound reinforcement circuit.
The power amplifier can be distinguished by its field of application. Usually there are two main areas of use: domestic and professional. They can also be divided according to the execution schemes into a single-cycle and two-cycle power amplifier. Single-cycle ones operate in the so-called linear gain mode. In this mode, current flows through the transistor for a full period.
The power amplifier is in absolutely any device or device that reproduces sound signals of the widest range of frequencies. Since the primary signal, which is read, usually usually has a rather small power, it is necessary to use amplifiers to transfer it to other devices. Such devices can be found in any mobile phone, tape recorder, in computers and laptops, and even in children's toys that can talk (which have speakers). In such household appliances, household amplifiers are also used. The purpose of such devices is to amplify the electric signal to values of the sound range that the human ear of the average citizen can perceive (usually from 15 to 22 kilohertz). It should be noted that with age, the range decreases significantly (mainly its upper limit falls), hearing becomes less sensitive - and most people aged are not able to perceive sounds at a frequency of more than 16-17 kilohertz.
Professional amplifiers, for example, a device such as a translational power amplifier, are widely used in industry. It is used for sound alerts in office buildings, industrial large enterprises and open areas, in stadiums and in entertainment centers. Their purpose is to amplify and transmit an audio signal for organizing broadcasting (signal broadcasting) at various large objects.
The appearance of such a device as a power amplifier can be the most diverse and vary greatly depending on its application and purpose. There may also be specific differences in design. For example, the sound power amplifier has a special system for reproduction, protection against water and moisture, and a permanent ventilation system. All this in total provides a much longer term for the operation of sound reinforcement equipment under maximum loads.