What do Headphone Amplifiers do

Have you ever had your headphones or speakers play distorted music, or experience crackling noises in the background?

This is not due to faulty equipment; it’s because your device is not pushing out enough power. To give you an idea of what this sounds like to the human ear, it’s like having your ears covered with wax. You can hear people talking, but they sound muffled and distant.

This article will detail what headphone amplifiers do and what impacts they have on the quality of sound. Our main focus is on headphones, but the same principles apply to home theatre systems as well.

Table of Contents

The Basics:

All sound is analog. However, the digital revolution has now made most audio equipment digital as well. For example, if you were to purchase a CD player or an MP3 player, then the music that you played will be converted into bits and bytes that can be streamed through your computer’s speakers without any problems.

However, the same cannot be said for headphones. These devices, by their very nature, still use analog signals to transmit music. They have a strain of copper wound around a central magnet that produces electrical currents, which is then transmitted along your headphone wire to your ear drum.

The advantage of being analog is that there is an infinite number of ways you can change the quality of the sound. One way to do this is with a headphone amplifier, which converts digital music files into analog signals and then amplifies them for your headphones or speakers to receive. This allows you to tailor the sound according to your preference by boosting certain frequencies and lowering others.

Why Do Speakers Need Amplifiers?

To understand the purpose of a headphone amp, it’s important to know what happens when you put speakers in your computer, walk away and return.

When the device is switched on, it immediately sends music through the speakers. However, after about 9 seconds or so, the sound starts to fade out (known as “sudden noise reduction”) because of the changing signal levels caused by pauses in music files.

As this happens, you can hear background noises like fans blowing and other noises that would certainly disturb others listening to music in public spaces.

This is where headphone amplifiers come into play; they keep these problems in check so that you can enjoy your favourite songs without any disturbances.

Difference Between Active and Passive Headphone Amplifiers?

Active Amplifiers are more common because they are powered by batteries or power sources. These are normally used for high-end headphones that have heavy-duty sound systems. You can also use these amplifiers with tube televisions to improve the quality of the speakers’ output.

Passive amplifiers, on the other hand, do not have any battery or power source. They rely completely on the amplifier’s output to keep them working. Also known as transformer amplifiers, passive devices are mostly used for low-power computer speakers and headphones that require less amplification than what active devices can provide.

How to Match Headphone with its relative Amplifier?

The most important factor when choosing a headphone amplifier is the power output. Most amplifiers come with a detailed table of what the device can deliver and how they match to your headphones. If you don’t know which amplifier to purchase, you can look at the features and specifications of the device and make a best match.

Some common factors that influence how well an amplifier works with your headphone are:

Headphone impedance: Within this range, there is an ideal matching between your amplifier and headphone.”That means that.” The higher the impedance (X), the lower the voltage (V) that will be sent by your sound card (A). The higher the impedance, the lower the voltage that will be sent by your sound card.

The lower the impedance, the higher voltage that will be sent by your sound card. This can be seen in real life when you plug in a pair of headphones with an impedance of 40Ohms to a sound card with an output of 8V. The headphone would receive 4V or less.[1]

Passive or Active?

Many headphone amps are completely passive. They don’t require any power source to work, which is what makes them ideal for devices like home theatre systems where removable batteries are not practical.

These amplifiers tend to give more punch and volume than passive devices due to their low power consumption. Active devices, on the other hand, require a 9V battery or power source to work (similar to how most computer speakers function). This gives the amplifier more power and volume output than passive amplifiers.

Active devices normally draw additional current from your battery, so they should be paired with high-capacity models if you want them to last long. The amp’s Voltage Gain or Voltage Output is an important factor in matching your headphones to the amplifier.

This specifies how much voltage will be sent out by the device if it has a range of 8V-16V. For example, if you were to match 16V with an amplifier that has a gain of 2(or x2), then you can expect 16 x 2 = 32 Volts.


There are many types of headphone amplifiers that you can choose from. If you plan to spend a lot of money on your new device, then we highly recommend that you buy one that has an output range of more than 16V and has an impedance of less than 600 Ohms.

If your headphones have a high impedance and there is no need for volume, then go for passive devices. If you only use the Internet or do simple office work, then passive devices will be great as well.

If you use an amplifier for business purposes such as watching videos, gaming or listening to music on your PC, make sure it supports your needs and is compatible with other devices in your workstation.