What is a Headphone Amp?
A headphone amplifier is simply a miniature power amplifier specifically designed to drive the tiny speakers inside headphones. Every headphone needs one to operate—which is why your phone, your computer, and your MP3 player all have amps in them—but some need more amplification than others.
Headphone amps are crucial with certain power-hungry high-impedance audiophile headphones that can benefit from the additional power of a dedicated amp.
Because headphones are often used with portable devices, some headphone amps are battery-powered for use on the go.
Some headphone amps also include built-in digital to analog converters (DACs) with a USB or optical port to connect directly with a laptop, PC or tablet, as well as optical and coaxial connections for compatibility with other digital audio sources.
Why do I need a headphone amp?
In case you're a visual learner, we have an excellent video on this topic from our in-house amp expert GoldenSound, check it out!
Just like a good speaker, good headphones can benefit from the additional dedicated power of a headphone amplifier to work their very best. With your favorite headphones, an uncompressed music source and a great headphone amp, you can be assured that you are getting the best possible delivery of your music.
While big speaker systems may out-perform headphones in terms of visceral sonic impact, great headphones can actually deliver superior audio resolution due to increased signal to noise ratio, meaning unpacking nuanced low-level information in the recording can be easier with headphones.
How do I know if my headphones need an amp?
While all headphones need an amplifier for the basic task of reproducing the sound, a few absolutely require a high-powered, dedicated headphone amp to perform well. When deciding whether to acquire a good headphone amp, it's important to consider how much a pair of headphones can benefit from an amp. In other words, their "performance ceiling"
If you spent more than $200 on your headphones, you probably want to consider an amp. An entry-level headphone amp like a Topping L50 Desktop Headphone Amplifier will help you get your money’s worth from your headphones and is an affordable gateway to the benefits of headphone amplification. However, if you want something a little more personalized and less focused on simple utility, you can browse our full line of headphone amps to find the best one for your needs.
Of course, an audio system is only as good as its weakest link. If you have well-recorded music and great audiophile headphones, but are relying on the power-limited headphone amp inside your smartphone, laptop or tablet to make the headphones sing, you may not be driving your headphones to their full potential.
What is a headphone amplifier actually doing?
You may know about a headphone's "impedance rating". Impedance is the combined resistance and reactivity the headphones present to the amp as an electrical load.
High-impedance headphones, like the Sennheiser HD 600, usually need more voltage to get up to a solid listening level, so they can benefit from a headphone amp especially with portable players that have limited voltage available from their internal batteries.
But very low-impedance headphones like the Hifiman Susvara or Moondrop Para lower the damping factor between the amp and headphones and actually require more current, which is less commonly abundant on most small-format headphone amplifiers. So there's a chance that low-impedance headphones may not be loud enough—and might even incur clipping (distortion) from a portable device, thus for these headphones the user experience can be significantly improved by adding a headphone amp.
The size and dimensions of your headphone may provide some basic clues as to whether an amp is warranted. Most earbud and in ear headphones are typically very efficient and less likely to benefit strongly from an amp. However, many larger over ear headphones will become clearer and better sounding with an amp. A few select audiophile models may even require a headphone amp to reach listenable volume levels and sonic performance, especially if connected to portable devices.
With a portable device, use a “line output” when available to connect to a headphone amp. If no line-out is available, use the headphone jack to send the signal over to the headphone amp.
When NOT to use an amp
Most in-ear headphones or IEMs are typically highly efficient so they work well with smartphones or other portable devices without requiring a dedicated external amp.
You do not need a headphone amp when using noise-cancelling headphones, as any wireless/bluetooth device will already have a built-in headphone amp inside. It prevents an external headphone amp from adding any significant audio benefit.
What about a DAC?
Just as with amps, DACs are an absolutely necessity to get headphones working in the first place. If you are listening to your music on a computer, laptop or tablet, you are already using a DAC. That said, a headphone amp with an internal digital to analog converter (DAC), or a separate DAC altogether can truly tie an audio chain together in a way that you have to try for yourself to know if its for you.
To learn more about DACs and how they work, check out this guide!
For more context, and a step-by-step guide to choosing components, check out our Buying Guide 2022: How to Navigate the Headphone Hobby