What is a headphone amp and why do you need one?

Of all audio components, the headphone amp category is one of the least understood. We suspect it's because there are currently so many different variations of headphone amps on the market. In this article, we will tell you why you may need a headphone amp and how to make the best purchase choice.

Why You Might Want a Headphone Amp

You have a set of headphones but your current audio component doesn’t have a headphone jack.

There are many pieces of home HiFi gear on the market that do not include a headphone jack. This is especially true as you move up into some of the very high performance separate audio components. Adding the right type of headphone amp is the best solution in this situation.

You have a set of higher impedance headphones and you cannot play them loud enough.

Several types of headphones on the market require a lot of power to play loud enough. These are normally of high impedance, above 100 ohms. Many headphone amps that are built into smartphones (and some other audio components), do not have an amp for the headphone section that is capable of providing enough power for the harder to drive headphones. Adding a good headphone amp will make your headphones come to life.

You want to use your headphones in another room or on the go.

While your main HiFi system may be in the family room, you might want to enjoy music in your office or another room. The right kind of headphone amp will allow you more freedom of choice in where you listen to your great set of headphones.

You want to improve the audio performance of your headphones.

If you are a music lover and enjoy the experience of hearing all of the subtle details in your music, the right kind of headphone amp can greatly enhance your listening experience. Smartphones delegate as little money as possible into the headphone jack, basically just enough to make it work. Many home audio components follow the same path. With an amplifier designed specifically for headphones with high-quality components, the upgrade in sound can be substantial. Some types of headphone amps will improve the digital signal as well through their built-in Digital to Analog Converter (DAC).

Types of Headphone Amps

Headphone amps can vary in size from a full-scale home audio component to a tiny piece that you can fold into the palm of your hand. Some are battery powered, while others need to be connected to AC power. You’ll also find a variety of different types of signals and inputs supported. We will break these down to help you decide the category that is right for your needs.

Analog Only

This type of headphone amp will have one or two analog inputs. This means you could plug a CD player or the audio output from your phone into it. Only a few amps will just have a phono input for a turntable, while all will have some kind of volume control and a headphone jack.

These amps are usually somewhat small in size, but since they all require AC power they are designed for home use only.

If your gear does not have a headphone jack, these amps are a fantastic choice for this type of use. The phono only, allows you to put together a great sounding turntable system with just a turntable and headphones for private listening.

Computer Audio Only

Many people love to listen to headphones on their computer but let's face it, the headphone jack on your laptop or desktop lacks quality. Digital files on your computer will also be converted to analog by the computers which are usually as cheap as they can be.

The good news is a new crop of amps will allow you to connect a USB cable from your computer to this type of amp. The amp will have DAC’s built-in which are far better than the ones on your computer, some even reclock the incoming signal for improved timing (that makes you tap your toes more to the music!).

There are two types of computer audio headphone amps. One will simply have a USB connector on it that plugs right into the USB jack on your computer. It will then have a standard mini headphone jack on it and you’ll control the volume through the computer. The other will be more of a component type where you will need to use a USB cable. This type will normally have its own volume control and full-sized headphone jack on the front

The amp which plugs directly in is powered off the USB jack. With the right kind of adapter cable, you can connect it to your smartphone for vastly improved audio while on-the-go.

Multiple Audio Inputs

Most headphone amps will fall into this category. These will have some combination of USB audio input for a computer or your smartphone, analog audio in, and/or digital audio in. Some home models will sometimes have more than one digital and analog input.

Multiple Audio Input headphone amps are either battery powered or portable. In addition to a great headphone amp section, these amps will have audio outputs capable of driving a power amp or feeding a pair of powered speakers.

Every component in your system can be connected with the headphone amp providing the switching. Amps that have extra audio outs that allow you to drive an amp or pair of powered speakers can help you put together a small, yet great sounding audio system in addition to improving headphone performance.

Streaming Options

A select few headphone amps give you the option of adding network streaming. This allows you to pull audio files off your network without being physically attached to your computer, and also to stream from your smartphone. Bear in mind, you can still connect one of the computer audio type headphone amps to your smartphone with some adapter cables.

How To Choose a Headphone Amp

As you can see, the types of inputs and where you can use a headphone amp are vary. We suggest you think about all of your possible use cases and choose the type that will cover all your needs.

Once you decide on the category you want to be in, you’ll likely find a wide price range to choose from. You’ll want to consider some or all of these qualities once you decide on the amp that suits your needs.

Form Factor

Some headphone amps can work well on-the-go, connected to your smartphone and as a home audio component. If your primary use is going to be on the go, you’ll want something lightweight and small in size. For home use only, you’ll find a lot of choices in the component size category.

Quality of the DAC’s and Audio Components

If one of the main reasons you are considering a headphone amp is the audio quality, you’ll want to pay special attention to the internal components of the amp. Normally the phrase “you get what you pay for” applies to headphone amps. If you are doing the analog-only type, you may find some with high-end tube output sections or pure Class A amps to drive your headphones.

If you are adding the digital audio side with computer audio inputs or optical in, bear in mind DAC’s vary greatly in sound quality. These will usually be rated at a sampling rate, the higher the better.

Very few manufacturers have the wherewithal to produce their own DAC chips so they buy an off the shelf model. It’s very easy to search for the part number to compare the raw pricing of DAC’s. We have found this to correlate very closely to sound quality.

Type of Output

If you plan to use your headphone amp with a power amp or pair of powered speakers, you will want to make sure it has a set of audio output jacks in addition to the headphone out. In some cases, the headphone out is capable of driving an amp or speakers. Most times if you see the output rated at higher than 2 volts, it should work in a variety of situations.

We hope you now have a better understanding of headphone amps and how to make the best choice for your system. To help narrow down your list of choices, we put together a list of the best headphone amps under $500 we feel offer the best value and sound quality across a wide range of choices.

Hopefully, you now have a better understanding of headphone amps and how to make the best choice for your system and needs. If you still have questions, our experts are available via phone and online chat to assist.