Power amplifier and voltage amplifier are two terms that you will stumble upon when choosing an amp. While both have amplifiers as a suffix, they are not the same. The power amplifier class is different than the voltage amplifier.
However, the question is, what really makes the amplifier voltage and power stand out? Well, that is what you will find out by going through this guide!
More Tips: Karaoke Amplifier: A Quick Beginner’s Guide
Types of Power Amplifiers
Before knowing about the things that set the power amplifier and voltage amplifier apart, you need to know about the types of power amplifiers. Let’s start with the power amplifier first. As the name suggests, power amplifiers boost power. These amps are divided into these three types:
- RF power amplifiers
- Audio power amplifiers
- DC power amplifiers
Read More: How To Hook Up A Home Audio Amplifier To a Home Stereo System?
Types of Voltage Amplifiers
Again, the name states it all! The voltage amplifiers will work to enhance the voltage level. And usually, these amplifiers are for small signal voltage. The transistor on the voltage amplifier will be pretty thin as it is not meant to handle the large currents.
Nonetheless, there are no types of voltage amplifiers. All of them are for one thing: working with small-signal voltage and amplifying the level.
Difference Between Power Amplifier and Voltage Amplifier
With the types and general description out of the way, let’s get to the thing that brought you in the first place. So, these are the things that make the voltage and power amplifier stand out from one another:
Output Impedance
The main difference between voltage and power amplifiers is the output impedance. While the power amplifier has low output impedance, voltage amplifiers have a high output impedance.
Magnitude of Signal
Another key difference between the amplifiers is the magnitude of the input signals. The power amplifiers will take large-sized signals, while the voltage amplifiers will work with a small signal.
Size
Usually, the power amplifiers will have a large form factor. That is because they will have large-sized transistors in them. In comparison, the voltage amplifiers will have a compact form factor. Why? Because they will have low to medium transistors in them.
Current Gain
The current gain for the power amplifiers is pretty high. Usually, it will be greater than 100. However, for the voltage amplifiers, the current gain will sit anywhere from 5 to 20.
Coupling
For the power amplifiers, transformer coupling will be used. On the other hand, voltage amplifiers will utilize RC coupling.
More Read: What Does Headphone Impedance Mean and How to Choose the Right One?
Conclusion
In short, the main thing that makes the power amplifier and voltage amplifier different is the output impedance. Other than that, power amplifiers are for high magnitude signals and have a high current gain.
But the voltage amplifiers will work with low magnitude signals and have a low current gain. That said, both of them will generally have negative feedback with a phase shift of 180 degrees.
Slava is a man of mystery and no-one seems to know exactly where he is at any point in time. When he isn't enjoying writing about all things audio and technical he can be found researching his next project of interest. The man never rests.