What Are Stereo Amplifiers and How Do They Work?

If you’re planning on hooking up your home with a good home entertainment system, you’ll first need a quality A/V receiver that will help to improve the overall sound quality of the system and a quality amplifier to give you the full effect. While it’s not always necessary to use an amp to enjoy your music, play games, or watch movies, it will provide your speakers with better sound quality.

So, what are stereo amplifiers and how do they work? A stereo amp is an electronic device that will help to increase the audio signal so you can hear it more clearly through your speakers. They work by taking the low-level audio output from the source and increasing it to a power level that can drive your speakers. However, the power output level will depend on the size of your amp.

What are stereo amplifiers?

A stereo amp is an electronic component that will boost an audio signal to create a loud and clear sound that you can hear through your speakers. If your audio system doesn’t have an amp, the sound from your radio will not be audible so you’ll barely hear it. You’ll need a greater power source that will generate that sound through your speakers and this will increase the power to the output and the quality of sound so you can comfortably hear the music through your speakers.

How do stereo amplifiers work?

Using a stereo amp is a very common way of improving the sound quality of any audio system and amplifying the signal in your home or office. To effectively power your speakers, a stereo amp will require an uninterrupted power source. The amp will get its power directly from your power source which is sent directly to your amp’s power supply. It’s then converted from an alternating current to a direct one that will flow in one direction to the transistor that will determine the amount of current that will flow through the circuit at any given time depending on the size of the input signal from the source.

Stereo amps use 3 wire connectors; a base, the emitter, and a collector. If a small current passes between the base and emitter, you’ll get a larger output current flowing between the emitter and collector. The input port to connect to the signal source, an output port for sending the signal to your speakers, and power input. These amps use transistors to control the amount of current that flows through and its frequency depending on the signal output. 

How do you choose the right stereo amp?

Before you choose the stereo amp you want to buy, you must choose an amp that will comfortably power your speakers to give you the best sound quality and ensure it doesn’t damage your system. Here are some factors you’ll need to consider.

Integrated or pre and power amps

An integrated amp has both the pre-amp and power amp in one unit which is great if you don’t have enough room for 2 separate units and you’re working on a budget. It’s simple, space-saving, convenient, and everything has already been tuned together so you don’t need to match the 2 amps. The pre and power amps are 2 separate boxes, one is the pre-amp has the input port and volume controls and can be very sensitive, and the other is the pre-amp that takes the weak signal from the pre-amp and gives it a boost so you can hear it through your speakers.


When choosing a stereo amp, good quality components are always heavier which will give you better sound. Although weight isn’t everything, it will give you a clue on whether the amp you want to buy is of good quality.


You need to think about the kind of inputs and outputs you’ll need on your stereo amp. Check the amp’s rear panel to see if you have options for the connecting sources, extra speakers, and future upgrades. These amps have RCA inputs that you can use with your usual sources like your CD player. One RCA input can be a phono input for connecting to a turntable and can handle very low signals and requires extra equalization. A stereo amp with XLR inputs that you’ll find in high-end sound systems that balance the audio. Some amps will have digital connections and digital inputs like USB ports or through wifi.


You must match your amp with your speakers, but you also need to consider its power output and impedance. The power output is how loud your music will be depending on the size of the room, while the impedance will show the voltage you need for the best performance of your device which is measured in ohms. This means the higher the impedance on your speakers, the more voltage your amp needs.

Factors that affect sound quality – Stereo Amplifiers

There are a few factors you need to consider that will help your amp improve your speaker’s abilities and sound quality.

PowerDifferent speakers need different amounts of power, some need low-pitched power while others need high-pitched power
Wire gaugeA thicker wire gauge will produce higher-quality sound in your speakers. Look for an amp that will improve the durability of your speakers and their overall performance
Bass responseAn amp should improve your speaker’s bass response
Internal factorsMost speakers use matching crossovers, buy better quality speakers and components.

Conclusion – What Are Stereo Amplifiers

With so many stereo amps in the market to choose from, you should choose one that will match your speakers and have enough power to run your speakers.


Do you need an amp for a subwoofer?

Subwoofers help to increase the bass frequencies to give you a deep, thumping sound and are mostly paired with an amp to boost the sound. However, you can still use the subwoofer without an amp if you know what to do.

Do power speakers need an amp?

No, they don’t. For a pair of powered or active speakers, one of the speakers has a built-in amp.  

Andrew Gibbons

According to Andrew Gibbons, playing the guitar is fun but it will take a few months before you can come up with a creative expression. Gibbons is a guitar instructor and has been teaching University music programs for over a decade, when it comes to playing the guitar a lot of factors come into play that determines the type of sounds produced. The guitarist must consider the guitar's neck and body shape, weight, and string type, the amp is also a primary determinant of the sounds produced and that is why Gibbons has created extensive excerpts detailing on the delicate topic. Guitarists must also pick a pose, be it the pro, wizard, hipster, or the old master.