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 tough to pick an amplifier due to the multitude of models and designs. I will explain some of the most common amplifier designs including “tube amps”, “linear amps”, “class-AB” and “class-D” along with “class-T amps” to help you understand some of the terms frequently used by amplifier manufacturers. This guide also needs to enable you to discover which topology is ideal for your particular application.
In other words, the objective of Cayin 300B is to convert a minimal-power audio signal in to a high-power audio signal. The top-power signal is large enough to operate a speaker sufficiently loud. To carry out that, an amp uses several elements which can be controlled through the low-power signal to produce a big-power signal. These elements range between tubes, bipolar transistors to FET transistors.
Tube amplifiers was once common several decades ago. A tube has the capacity to control the current flow based on a control voltage that is attached to the tube. Unfortunately, tube amplifiers possess a fairly high amount of distortion. From a technical perspective, tube amplifiers will introduce higher harmonics in to the signal. However, this characteristic of tube amps still makes these popular. Many people describe tube amps as having a warm sound versus the cold sound of solid state amps.
Another drawback of tube amps, though, is the low power efficiency. Nearly all power which tube amps consume has been dissipated as heat and merely a fraction has been converted into audio power. Also, tubes are very expensive to make. Thus tube amps have mostly been replaced by solid-state amps that i will look at next.
Solid state amps replace the tube with semiconductor elements, typically bipolar transistors or FETs. The earliest type of solid-state amps is referred to as class-A amps. In class-A amps a transistor controls the current flow based on a tiny-level signal. Some amps utilize a feedback mechanism so that you can minimize the harmonic distortion. Class-A amps hold the lowest distortion and usually also the lowest quantity of noise for any amplifier architecture. Should you need ultra-low distortion then you certainly should take a closer look at class-A models. The main drawback is that similar to tube amps class A amps have really low efficiency. Consequently 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 Speaker Cable. They utilize a series of transistors to interrupt the large-level signals into two separate areas, every one of which can be amplified more efficiently. Therefore, class-AB amps are often smaller than class-A amps. However, this topology adds some non-linearity or distortion in the area in which the signal switches between those areas. As such class-AB amps normally have higher distortion than class-A amps.
Class-D amps improve on the efficiency of class-AB amps even further by using a switching transistor which is 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 is being controlled with a pulse-width modulator. The switched large-level signal has to be lowpass filtered in order to remove the switching signal and recover the audio signal. Due to non-linearities of the pulse-width modulator as well as the switching transistor itself, class-D amps by nature have among the highest audio distortion for any audio amplifier.
To resolve the problem of high audio distortion, newer Line Magnetic 219ia incorporate feedback. The amplified signal is in contrast to the first low-level signal and errors are corrected. A highly-known architecture which uses this type of feedback is known as “class-T”. Class-T amps or “t amps” achieve audio distortion which compares using the audio distortion of class-A amps while at the same.