Most systems intended for sound playback have a special additional device called sound amplifier. With its help, the sound is transmitted quite loudly, without foreign electromagnetic interference and various distortion. Amplifiers differ from each other by their construct, and also have different applications and synchronization with another audio engineering.
Sound power amplifier can be embedded in a system of any device or be a separate independent device having its control panel.
What it is?
Sound amplifier can be found in any high-quality equipment of the speaker system. It can be a radio tape recorder for listening to music in a car, a music center, a home theater or a regular sound player, a phone or a laptop – in a word, the amplifier will apply wherever the equipment provides speakers. The amplifier is a device that runs from the electrical network and converts the electric signal, making it stronger compared to the initial parameters due to the increase in the power of the electric current.
Devices for amplifying sound are divided depending on the scope of their use. The main applications of amplifiers are professional and household. In addition, the amplifiers can be classified based on their design schemes – there are disputed or two-stroke options. For example, the one-stroke amplifier operates in linear amplification mode, when the transistor passes through the transistor during the full period.
The task of a household amplifier – to give the sound an additional power, bring the beep to such indicators of the range that can hear the ear of an ordinary person, that is, up to 15-23 kHz. Such an increase in sound expocration is justified by the fact that with age in humans, hearing susceptibility decreases, and people of mature age perceive sounds at a frequency not higher than 16-18 kHz.
Industrial sound amplifiers are also important and widespread use. They are used for information alerts in buildings and facilities, industrial workshops, on open venues, as well as in large shopping or spectacular centers.
The purpose of using such devices is to strengthen and convey information to all listeners who are located on large areas of the territories.
Any sound power amplifier has certain characteristics.
- Power output sound – It happens the nominal, which is measured relative to the established coefficient of distortion of the sound of nonlinear order, or the maximum, that is, the measured relatively arbitrarily defined coefficient.
- Efficiency – determines the parameter of the amplification of the sound relatively initial power of its sound.
- Frequency range – Indicates which frequency fluctuations can work enhancement device. Usually it ranges from 20 to 22 kHz.
- Harmonic distortions – This is a coefficient that determines a part of distortions that are present when transmitting reinforced sound on a reference frequency of 1 kHz. Distortion can be from 0.001 to 0.1%.
- Sound and noise ratio – shows the level of how their own sounds of the sound inside correlates with the enhanced sound transmitted by them.
- Dumping factor – reflects the possibility of an amplifier to stop unwanted interference, arising in the field of electrical stress, which can significantly affect the quality of sound transmission.
In addition to the specified characteristics, the audio amplifier can be estimated according to the degree of intermodulation distortion, the presence of cross-electromagnetic interference, as well as to determine the speed of the outgoing sound.
For what is needed?
Often the people have a question, why do you need a sound amplifier, if you can just add volume. However, the amplifier not only adds volume, but it also gives the power transmitted. Various devices that serve to transmit sound can not always pass it with high quality levels. But if you connect these devices to the enhancement equipment, the outgoing sound will significantly change its characteristics:
- The audio signal at the outlet becomes better, It is protected from exposure to distortion and various interference;
- The opportunity appears broadcast the sound is several times louder and more powerful compared to its initial state.
When applying the amplifier, you do not have to use the volume of the volume, and you can extend the life of the speakers of a device.
Device and principle of operation
Consider how the usual amplifier is arranged, which works to enhance sound in audio colors.
- An important detail is the entry system to which the sound source is attached. Between the source and amplifier, the input voltage is usually different.
- Transformer – It converts power supplied to an electric flow amplifier in value with high indicators.
- Output cascade – It consists of transistors that perform the task of converting the high voltage of the electric flow coming from the power supply. From the output cascade, the transformed signal is transmitted to the output sound device.
- Adjust the settings – This unit can be found only in autonomous type amplifiers. Using the adjustment, you can select the quality level of the transmitted audio signal.
Next, a scheme of the sound power amplifier has a conventional sample device.
- Electric current from the power supply or automotive power supply system, Provided by the battery, entering the transformer, is converted to DC parameters.
- Converted and enhanced beep, without changing the length of the sound waves, Enters the output device, from where it sounds in a better and most powerful. Usually such a broadcast is performed by audio colors.
A reinforcing device used for household equipment, such as a computer or tape recorder, also across the input system receives a signal from the connected sound source, converts it with an increase in the power of the amplitude of the vibrational waves and transmits the sound to the output device.
What are there?
Modern audio equipment is equipped with a sound amplifier – whether it is a device that transmits a digital processor signal or a wireless gadget, the operation of which is carried out with Bluetooth, you can detect both the monoxylter and the stereo-model. Enhanceing sound The device may look like a mini-amplifier used in devices with small dimensions, and, for example, a smartphone has a built-in microSilletel. Say that a big amplifier is better than a small, it would be wrong.
No matter what type or type an amplifier is used, it will perform its function based on its design opportunities.
Options for sound power amplifiers are divided with the scope of their application.
- Sound amplifiers for automotive audio systems – designed to increase the power of speakers and subwoofer. Are divided into devices having from 1 to 6 channels. Single-channel option works with high power devices. Two-channel option works with an audio system with separate channels that form stereo sound. Three-channel devices have the ability to connect to the subwoofer and two columns. The most common amplifier with four channels, where you can connect 4 speakers or 3 speakers and subwoofer. Amplifiers with 5 and 6 channels also enable maneuver in connecting multiple audio devices, significantly saving free space, but they are more expensive at cost.
- Amplifiers for household audio – Separate amplifiers are rarely found, since any media technique already has them in the embedded version. For this reason, the use of an additional amplifier in everyday life is not necessary to increase the power of the sound, but to eliminate possible interference when it is transmitted. This option is performed due to a special block that controls the timbre, reinforcing or, on the contrary, reducing high and low sound frequencies.
- Concert amplifier – This is a professional type of equipment designed to synchronize with musical instruments having a connection to the power supply. The device of such an amplifier includes more and dynamics, a block of various special effects, as well as a sound timbre control unit.
- Studio amplifier – Also relates to a professional type of equipment whose task is a slight increase in sound and the maximum increase in its quality. The studio amplifier has a lot of differences compared to everyday. They consist in a higher sensitivity range reaching up to 100,000 Hz, the channels are adjustable separately, and instead of the tone adjustment unit, the studio amplifier has a mixed console. Studio equipment is much more powerful and designed for heavy loads in the duration of use, has protection against electrical voltage jumps, has more reliable and high-quality connectors and so on.
Devices that enhance the sound, in addition to its purpose, are also divided into power levels.
By class of power
Under the power level understand the total output signal, which is taken into account in one device cycle, depending on its device scheme.
Conditionally, the power classes of the sounds are divided into several groups.
The highest quality – classes A, B, AB, with. Such devices are able to provide the most pure and free from interference analog sound. In the design of the device lies the transistor or lamp method for conversion of sound. Such equipment is used in household and professional spheres.
The most qualitative conversion of sound is carried out only with the help of a class A lamp amplifier. These devices are expensive, and they can reach several million rubles. Lamp-type amplifiers have the ability to absolutely accurately copy the appearance of the input audio and output it without any distortion, but with a significant accurate share.
The disadvantage of such high-class equipment is not only its cost, but also the high amount of electricity consumed.
Devices for small-sized devices – Classes D, E, F and T. Digital circuits are used in these amplifiers, as well as modulation of pulsating power on and off.
Most common Amplifiers of class D, which, in contrast to analog species, the input signal is not obtained in the form of sinusoids, but as a rectangular impulse. The amplitude of the pulses is constant, and their duration depends on the input signal. The device operates at a frequency of 10 to 100,000 Hz. Forming sound pulses are amplified using transistors, and the outgoing sound passes low frequency filtering.
Amplifier for automotive equipment – class H. This technique is used under conditions with limited level of electric shock. Constructive device includes an AB-class amplifier. The efficiency of such an amplifier is 83-85%, and it is considered a low-power, but the sound distortion indicator is only 0.1%.
Choosing a sound amplifier, focus not only on its scope, but also on the class of its operating power.
To select the amplifier model, you should consider not only the vintage parameters of its appearance and properties, but also to focus on the reviews of acoustics professionals. Amplifiers can be quite large, as well as compact models. Built-in devices have a very miniature view, but is simply a portable version used in a car.
As an example, consider some modern models.
- DENON PMA-520AE – Reliable two-channel model, the output power of which is 70 W per 1 channel. The transistor integral amplifier operates in frequencies from 5 to 100 kHz. The distortion coefficient is 0.02%. Cost 18,000-20 000 rub.
- Pioneer A-30 – integral two-channel transistor amplifier, class speaker. Channel power 70 W. Works in the frequency range from 5 to 100 kHz. Cost 25,000-28 000 rub.
- Marantz PM5005 – integral transistor two-channel amplifier, with a power of 40 W per channel. Works in the frequency range from 10 to 20 kHz. The distortion coefficient is 0.01%. Cost 25 000-30 000 rub.
- ONKYO A-9150 – integral transistor amplifier, two-channel, class AC. The power of each channel is 60 W. Works in the frequency range from 10 to 100 kHz. The distortion coefficient is 0.08%. Cost 45 000-60 000 rub.
- Yamaha A-S801 – integral transistor amplifier, two-channel. Power on each channel is 100 W. Works in the frequency range from 20 to 200 kHz. Capacitors have a power of 12 μF. Cost 55,000-60 500 rubles.
The listed models are not new production, but have already managed to gain popularity among users during their use.
How to choose?
To choose a suitable model for active audio acoustics, be it a miniature car amplifier or a large-sized device for outdoor concert equipment, There are certain parameters to be paid attention to.
- Before buying an amplifier, first of all you need to choose acoustic equipment And only then, focusing on its parameters, select the device reinforcing. Both devices must be synchronized with each other on the power and frequency of the operating range.
- Choosing a reinforcing sound device, you need to take into account that area of the room or open space on which he has to work.
- For durable work reinforcing the sound of equipment Experts recommend choosing it with a power reserve regarding the one you need. Do this in order not to use the amplifier at the limit of its capabilities.
- High quality equipment has a level of sound distortion within not exceeding 3%. The lower this indicator – the better the amplifier.
- The signal indicator level / noise in the enhancing device must be as high as possible – It gives an idea of the purity of the sound at maximum volume option.
- Amplifiers work in different frequency ranges, but the best will be the device that can function at frequencies from 16 to 100 kHz. In this range, the sound quality of the human ear perceives best.
Exact and detailed characteristics Each manufacturer indicates instructions for its products, you will only learn to recognize them and compare between several models of one price segment.
About how the sound amplifier works, you can find out below.