Audio amplifiers are at the very heart of every home theater system. As the quality and output power requirements of today’s loudspeakers increase, so do the demands of audio amps. It is difficult to pick an amplifier because of the large number of models and styles. I will explain some of the most common amplifier designs such as “tube amps”, “linear amps”, “class-AB” and “class-D” as well as “class-T amps” to help you understand some of the terms widely used by amplifier manufacturers. The following information must also enable you to discover which topology is great for your particular application.
To put it simply, the purpose of Cayin A88t Mk2 is always to convert a minimal-power audio signal in to a high-power audio signal. Our prime-power signal is big enough to drive a speaker sufficiently loud. To carry out that, an amp uses one or more elements that are controlled by the low-power signal to create a large-power signal. These elements range between tubes, bipolar transistors to FET transistors.
Tube amplifiers used to be common several decades ago. A tube has the capacity to control the present flow according to a control voltage which can be linked to the tube. Unfortunately, tube amplifiers have a fairly high amount of distortion. Technically speaking, tube amplifiers will introduce higher harmonics into the signal. However, this manifestation of tube amps still makes these popular. Many people describe tube amps as using a warm sound versus the cold sound of solid state amps.
Another problem with tube amps, though, will be the low power efficiency. Nearly all power which tube amps consume has been dissipated as heat and just a fraction will be converted into audio power. Also, tubes are very expensive to make. Thus tube amps have mostly been replaced by solid-state amps that i can look at next.
Solid state amps replace the tube with semiconductor elements, typically bipolar transistors or FETs. The earliest kind of solid-state amps is known as class-A amps. In class-A amps a transistor controls the current flow in accordance with a small-level signal. Some amps use a feedback mechanism so that you can minimize the harmonic distortion. Class-A amps have the lowest distortion and often even the lowest amount of noise of the amplifier architecture. If you want ultra-low distortion then you should take a close look at class-A models. The key drawback is that similar to tube amps class A amps have suprisingly low efficiency. Because of this these amps require large heat sinks to dissipate the wasted energy and therefore are usually fairly bulky.
Class-AB amps improve on the efficiency of HIFI RCA Cable. They normally use several transistors to break up the large-level signals into two separate areas, every one of which can be amplified more effectively. Therefore, class-AB amps are usually smaller than class-A amps. However, this topology adds some non-linearity or distortion in the region in which the signal switches between those areas. As a result class-AB amps routinely have higher distortion than class-A amps.
Class-D amps improve on the efficiency of class-AB amps even more simply by using a switching transistor which can be constantly being switched on or off. Thereby this switching stage hardly dissipates any power and phczif the energy efficiency of class-D amps usually exceeds 90%. The switching transistor will be controlled with a pulse-width modulator. The switched large-level signal must be lowpass filtered in order to eliminate the switching signal and recover the audio signal. Due to non-linearities in the pulse-width modulator and also the switching transistor itself, class-D amps by nature have between the highest audio distortion of the audio amplifier.
To solve the issue of high audio distortion, newer Line Magnetic incorporate feedback. The amplified signal is compared with the original low-level signal and errors are corrected. A properly-known architecture which uses this sort of feedback is referred to as “class-T”. Class-T amps or “t amps” achieve audio distortion which compares with all the audio distortion of class-A amps while in the same.