Anyone who attends a concert, let alone listens to music in any form or fashion, is aware of the power amplifiers have, although they are not as informed about power amplifier classes. Power amplifiers (sometimes known as amps) have the ability to heighten the signal a particular sound, which will include the bass, treble, etc.
It’s not unusual for a teenager to attend his first dance in middle school. Along with the excitement regarding the prospect of attending the dance, the student picks out a spot that allows him to scope out the room. He feels lucky to choose a spot close to the stage, but his excitement is short lived once he is aware of the power amplifiers have once the music kicks into gear. Unfortunately, it is a lesson that will not be forgotten, especially since the power amplifiers ring in his head until the morning hours. Little does the student know his introduction to power amplifiers will be so memorable.
Although knowledge of power amplifiers is familiar territory in the music arena, information of power amplifier classes may not be as recognizable. Power amplifier classes include A, AB, B, C, D, E, F, G and H. Power amplifier classes
Power amplifier classes A, AB, and B (linear)
Power amplifiers class A are the least efficient of amplifiers. This power amplifier class is likened to listening to in an increased form that is heard through the headphones of a simple portable CD player or mp3 player. This amplifier uses 100% input.
Power amplifier class AB operates between class A, which is linear, and class B, operates at a higher efficiency. It operates at 50% of the input without ever using the full 100% like power amplifier class A does. This equates to power amplifiers in class AB being capable when the transistor is on for more than a half cycle. However, it can also be lower than the full cycle of the signal.
Power amplifier class B concludes linear power amplifiers. This amplifier class has higher efficiency than either the A or AB class of amplifiers. Power amplifier classes B function at an inactive current. When comparing B class to the former classes, power amplifiers in the B class operate at an efficiency of 80 to 85%.
Power amplifier classes C and F (non-linear)
The uses of non-linear amplifiers establish that efficiency is critical.
Power amplifier class C is one that the output current remains at zero for more than 50% of the input signal cycle. A necessary part of the power amplifier class C is a tuned circuit.
Power amplifier class F will be the final classification we will discuss in this article. This non-linear amplifier classification is one with the highest efficiency. This power amplifier class has a current that is shaped to minimize their overlap.
Other High-Efficiency Classes include
D, E, G, H, and S