Amplifier Classes

All amplifiers work differently from each other in design and logic, and there is a clear distinction between the configuration and the way the output stages work. The main working characteristics of an ideal amplifier; linearity is signal gain, efficiency and power output, but amplifiers always have a balance between these different characteristics; Under this heading, we will examine the range of class A, class B, EU class, class C, class D, class T. But before that, we will talk about basic sound terms.

Stereo and Dual Mono Amplifiers

Although both types of circuits are quite similar in terms of their general characteristics, they also have some important differences. In stereo amplifiers, the circuits of the right and left channels are separate, but the circuits and power supply that control them are common. In dual mono structure, two amps operate in the same chassis with almost no common elements except the main power transformer. In fact, in some designs, the power transformers are completely separated. The biggest advantage of Dual Mono amplifiers is that the signals in the two independent channels are ins isolated from each other as much as possible, thus preserving the recording audio scene as much as possible. The most obvious advantage of stereo amplifiers is their relatively low costs.

What is Mono?

It is a short and common use of the Latin word Monoaural, which refers to recording or listening through a single channel. Mono audio sounds exactly the same from one or more speakers, and there is no information that provides depth perception. When mono recordings made in the pre-stereo years are listened to in modern stereo systems, the sound is perceived as coming from the middle of the speakers.

What is Stereo

It is a short and common use of the Latin word Stereophonia (identical sound). It refers to music reproduction in a way similar to our hearing with both ears. It is achieved by placing two or more speakers at an equal distance from the listener and driving them through independent channels. It provides a more realistic listening than single-channel mono listening.

What is Analogue and Digital Audio?

The analogue word means identical to the original. In sound terminology, it indicates that the electrical signal is continuous, just like sound waves, during recording and listening. The word digital means numeric, and digital audio means audio stored or published in digital environment. Digital audio signals are digitized from analog originals or by dividing them into numerous neighboring slices with analog-digital converters during direct live recording. The multiplicity of these slices ensures improved quality in sound. When digital audio signals want to be listened to, they are converted back into analog electrical signals with digital-analog converters. For example, all CD players have these converters.

Types of Amplifiers

Transistor Amplifier

They are amplifiers that use semiconductor transistors for signal processing and amplification. It is the type of amplifier that is widely produced and preferred today.

Lamp or Tube Amplifier

Vacuum tubes are used for signal processing and amplification. Contrary to popular belief, tube audio devices are not ancient objects, but products that offer very high performance within today's standards when they are well designed and manufactured. Generally, the cost of getting high performance is higher than transistor amplifiers.

Power Amplifier

They are devices that serve to increase the low electrical volume sound signals from the source devices or preamp to the high voltage and current level that the speakers need. it can be in individual chassis with preamp or it can be a single chassis in the form of an integrated amplifier.

Integrated Amplifier

It is the type of amplifier in which the pre and power amplifiers are presented as a single device on the same chassis. It is the type of amplifier preferred by the majority of music lovers as it does not require interconnect cables and provides practicality in placement. For this type of amplifier, resource selection, voice control, and upgrades are all performed on one device.

Preamp / Pioneer Amplifier

It is a pre-amplifier that serves to amplify weak sound signals to a level that the power amplifier can detect. It usually also performs resource selection, volume control and similar functions. It also prevents impedance problems that may occur when a direct connection is made between source devices such as a CD player or radio and the riser.

Class A Amplifiers

Such amplifiers are processed by a single output element while maintaining wave integrity when upgrading the signal from the source. Depending on the quality of the output transistoru or tube and circuit design, the original waveform is best maintained and the smoothness and integrity of the sound are at the highest level. They have a very high operating temperature as they constantly attract a constant current with or without signal at the entrance. Quality and soft sound level, lowest dispersion level and fast bass performance are extremely useful circuits in terms of acoustic planning but are at a disadvantage in terms of high temperature range and electricity consumption. Amplifier

Class B Amplifiers

Class B amplifiers also increase only positive or negative half of the input signal in order to increase electrical efficiency. In pairs, each half of the signal is combined to output the full sound signal. Here, class B amplifiers heat up less than class A circuits, as each transistor only receive electricity in its own working zone; approximately 30% of your energy turns to heat, and they work more efficiently. The biggest problem with such amplifiers is the deterioration caused by synchronous disorder during the transition between positive and negative signal regions. It's called crossover corruption. Due to this distortion, they are often found in industrial applications instead of designs close to the most natural state of sound, they are used with high efficiency and light designs, but are not preferred for high-quality sounds. Amplifier

EU Class Amplifiers

Class B is a group of circuits that allow the transitional and complementary output floors of the amplifiers to be specially arranged and operate in class A format up to a certain signal height. Here, the bias current of the output transistorus or tube is adjusted to be kept alive with a very low bias current without shutting down in the absence of signal, as opposed to class B, ensuring that the device is not affected by crossover distortion. This circuit type is the most widely used design among commercial productions, they are the most preferred types with high efficiency, light designs and low heat generation, but it does not have as high quality sound level as class A, it is literally the average of class A and B. Amplifier

Class C Amplifiers

It is a circuit design that activates the output elements in proportion to the height of the input signal. It is usually used in telecommunications, radio and other sound systems that are intended to work only on the speech band. Hi-fi is not used in music systems, provides high efficiency but low sound quality. Amplifier

Class D Amplifiers

Circuits that use the principle of amplification obtained by overlaying pulses in the square wave form of the input signal. Theoretically, it works with 100% efficiency, but the distortion created by the wave carrier is filtered with a special filter circuit just before the output stage to obtain a clean signal. Successful designs can be made in proportion to the frequency and cleanliness of square wave modulation. This increasingly common circuit type active subwoofer is successfully used in systems where broadband sound quality is not vital, such as high-power announcement systems. In recent years, competition between traditional linear circuit types and modulated class D has been increasing, the sound quality difference is decreasing, very high efficiency has advantages such as almost non-heating, but it is an inadequate design in pronounced coldness quality and analog output sounds. Amplifier

Class F Amplifiers

Class F circuits increase both efficiency and output by using harmonic resonators in the output network to format the output waveform in a square wave. Class F amplifiers have a higher yield of more than 90% when infinite harmonic adjustment is used.

Class G Amplifiers

This circuit design consists mainly of the composition of a gradual feeding circuit with the philosophy of output of EU classes. Instead of the constant feed voltage in the EU designs, the voltage stages that the output elements may need are pre-selected in proportion to the amplitude of the signal at the input. In this way, a more electrically efficient operation is ensured. This technique is mostly common in amplies used in professional voiceover. It is preferred with high efficiency and high sound quality, but permanent failures in circuits that are not designed properly due to amplitude deterioration. Amplifier Amplifier

Class H Amplifiers

They are similar to G-class designs, but here the feed voltage of the output elements is controlled more precisely by stepless or numerous stages in proportion to the signal at the input. In such circuits it is often used in professional tour giants with high-power and extremely expensive high-end circuits. Many versions use high frequency switch mode circuits instead of the classic analogue feed solid. It is one of the most efficient designs known as electrical, but poor quality sounds in expensive and low-budget work. Amplifier

Class I Amplifiers

Class I circuits have two complementary output switching devices arranged in parallel push-pull configuration with both sets of switching devices that sample the same input waveform. One device changes the positive half of the waveform, while the other changes the negative half in a similar way to a class B elevation. When the input signal is not applied or a signal reaches a zero pass point, switching devices produce both ON and OFF signals at the same time as the 50% PWM operating cycle that cancels high frequency signals.

Class S Amplifiers

An S-class power amplifier is a nonlinear switched mode amplifier, similar to a class D amplifier. The class S amplifier converts analog input signals into digital square wave pulses by a delta-sigma modulator and eventually amplifys them to increase output power before being demodulated by a band transition filter. Since the digital signal of this switching amplifier is always completely "ON" or "OFF" (theoretically zero power consumption), yields reaching 100% are possible. Amplifier

Class T Amplifiers

T-class amplifiers are becoming more popular these days as an audio amplifier design, as they convert analog signals into PWM signals due to the presence of digital signal processing (DSP) chips and multichannel surround sound amplifiers. Magnify by increasing amplifier yield. T-class amplifier designs combine both low distortion signal levels of the EU-class amplifier and the power efficiency of the class D amplifier. Amplifier

Efficiency and Angle Table