Compared with normal amplifiers, professional amplifiers have larger output power, higher signal-to-noise ratio, higher stability and lighter weight. There are some characteristics of different types of professional amplifiers.
Class AB amplifier is classic analog amplifiers with mature technique. Actual efficiency is 30%~50%. Power of a Class AB amplifier with 2U depth hardly surpasses 1000W. Class H and Class G amplifier is improved to two-stage or multistage-step power supply based on class AB. Actual efficiency is 50%~70%. Class TD amplifier is improved to supply power according to output voltage based on Class AB. Actual efficiency is 70%~80%. When volume is the same, output power is higher. Class D amplifier is also called digital amplifier. Actual efficiency is 90%. It is always equipped with switching power supply which makes it lighter. With 1U height, its output power could be thousands or higher. In developed countries, analog amplifiers have been widely replaced by digital amplifiers.