Most audio interfaces have headphone amps. Audio interfaces with a headphone jack with a dedicated headphone volume knob have a built-in headphone amp. However, headphone amps in audio interfaces are usually not as powerful and quality as dedicated headphone amps.
I know for a fact that many people can’t tell an audio interface from a headphone amp. And while these devices may look quite similar, they are two totally different devices. And at the end of this article, you should know the difference between a headphone amp and an audio interface.
I’ll also answer some of the most common questions people have regarding audio interface and headphone amps. So before you click away, do well to go through the entire article because I will answer every question you have. Let’s get into it.
Audio Interface vs Headphone Amp: What’s the Difference?
So what’s the main difference between an audio interface and a headphone amp?
An audio interface is a device that converts analog audio signals, usually from a microphone or a musical instrument, into a digital format for computers. It also converts digital signals from a computer to analog audio signals to be played through headphones or studio monitors. On the other hand, a headphone amp is a device that amplifies an audio signal from low voltage to a voltage sufficient enough to drive headphones
That is an oversimplified definition of an audio interface and a headphone amp. Let’s dive a little deeper into what these devices are and how different they are from each other.
An audio interface is an all-in-one device that allows you to record and playback audio to and from a computer.
When it comes to recording, audio interfaces provide you with audio inputs that allow you to connect a microphone or a musical instrument. This means you can record audio directly with a microphone connected to the interface or record the sound from any musical instrument plugged directly into the audio interface.
Also, most audio interfaces available today have a built-in preamp that boosts a weak microphone or instrument signal into a line-level signal, suitable for recording.
Usually, audio interfaces are also capable of supplying 48V phantom power to condenser microphones to power them.
After capturing an audio signal with a microphone or an instrument, the built-in Analog to Digital converter (or ADC) in an audio interface converts the analog audio signal into a digital format that a computer can read.
When it comes to playback, audio interfaces have audio outputs to connect to a pair of speakers or studio monitors. There is always at least one pair of stereo output channels on every audio interface. However, some audio interfaces come with multiple output channels. And this allows you to route different audio signals through the different channels.
Also, many audio interfaces available today have a headphone output. There is always at least one headphone output on interfaces. But once again, some audio interfaces have multiple headphone outputs.
This means audio interfaces have a built-in headphone amp that drives the headphones connected to the headphone outputs.
Also, audio interfaces have a Digital to Analog converter (or DAC) that converts audio from digital format to an analog audio signal so that it can be played through speakers, monitors, and headphones. I have a dedicated article on how audio interfaces work as a DAC. You should definitely check it out.
A headphone amp is a device that amplifies an audio signal from low voltage to a voltage sufficient enough to drive headphones. What a headphone amp does is it takes an audio signal in the form of an electrical voltage and then boosts the voltage. The boosted audio signal is then sent to the headphones connected to the amp.
Think of headphone amps as regular speaker amplifiers, but less powerful. They are designed to drive headphones that require less power compared to speakers.
Why would you need a headphone amp? Glad you asked.
Well, some high-end headphones are high impedance headphones. And high impedance headphones require more power to drive them. The amount of power required by these headphones cannot be supplied by your computer or smartphone’s built-in headphone amp.
If you connect a high impedance headphone to a low-powered headphone amp, this can result in an audio signal that is not loud enough, a distorted audio signal, or the frequency response of the headphones will be altered. And this can result in an inaccurate sound from the headphones. And this is why having the right headphone amp for your headphones is important.
Also, many headphones have a single output jack. This means you can connect only one pair of headphones to them. However, there are some headphone amps with multiple outputs, allowing you to connect more headphones at a time.
Musicians use multiple-channel headphone amps to help them play along to a click track or communicate using a talkback microphone.
The most sought-after multiple-channel headphone amp used by musicians is the Behringer Powerplay HA8000 Headphone Amp (on Amazon). This is an 8-channel headphone amp, meaning you can connect up to 8 headphones to it.
And this headphone amp is not only capable of playing the same through all of the outputs, but it also has an individual input channel for each output. This means all of the eight different channels can have their own unique audio playing through them. And honestly, that’s a really well-thought-out headphone amp. We use the Behringer Powerplay HA8000 in our church’s in-ear monitoring system. And it gets the job done.
Can You Use an Audio Interface as a Headphone Amp?
You can certainly use an audio interface as a headphone amp. Most audio interfaces have a headphone output, and this means they have a headphone amplifier built into them.
Audio interfaces have a feature called direct monitoring. This feature allows you to listen (or monitor) the audio signal being captured by the input channels. This handy feature is built into audio interfaces to allow musicians to listen to their performance as they record.
With the direct monitoring feature, you can plug an audio source into the audio interface’s inputs and listen to the audio with headphones using the headphone output. Here’s the point I’m trying to make.
To use an audio interface as a headphone amp,
- Plug an audio source into the audio interface’s input channel
- Use direct monitoring feature on the audio interface to route audio input to the headphone output
- Listen to the audio using a headphone connected to the headphone output.
Although you can use an audio interface as a headphone amp, there are some reasons why dedicated headphone amps are a better option. Let’s take a look at them.
Are dedicated headphone amps better than audio interface headphone amps?
As we’ve already discussed, audio interfaces are all-in-one devices for recording and playing back audio. A typical audio interface will have an audio input and output channels, preamps, a Digital to Analog Converter (or DAC), an Analog to Digital Converter (ADC), and a headphone amp.
These are all components that can exist as a standalone device. But audio interface manufacturers find a way to put it all together into a single unit. And this comes with many compromises.
The quality of components used in audio interfaces and the electrical and electronic circuitry design is greatly compromised in an effort to make audio interfaces affordable and budget-friendly.
Due to this, dedicated headphone amps usually sound much better than the audio interface’s built-in headphone amps. That’s because dedicated headphone amp manufacturers actually spend a lot of time and resources on designing the amp.
However, this is not to say the audio interface’s headphone amp sound totally crap. That’s not the case at all.
Headphone amps in the audio interface sound quite decent. They sound way better than laptops and smartphone headphone amps. And you may barely notice any difference between a standalone headphone amp and an audio interface’s headphone amp if you perform a blind test between the two.
Also, most audio interfaces are not powerful enough for high-end headphones. Many of the budget-friendly audio interfaces such as Focusrite Scarlett 2i2 (on Amazon) or the Presonus Studio 24C (also on Amazon) can drive low impedance headphones like the Audio Technica ATH M50x or the Sennheiser HD280 Pro headphones. These are headphones that require low power to drive them.
However, these audio interfaces are simply not powerful enough to drive high impedance power-hungry headphones.
However, decent-priced dedicated headphone amps are usually powerful enough to drive any headphones you plug into them. So that is another advantage standalone headphone amps have over audio interface headphone amps.
In summary, the point I’m trying to make is, a $500 headphone amp will sound much better than the headphone amp in a $500 audio interface.
Regardless of the fact, there are some high-end audio interfaces with quality components, including a much better-sounding headphone amp. Let’s take a look at some of them.
Audio Interfaces with the Best Headphone Amps
Here are two audio interfaces with the best headphone amps available today
While I was researching this topic, one audio interface that stood out the most was the MOTU M4 Audio Interface (on Amazon). Based on many tests, comparisons, and user reviews, this audio interface has one of the best headphone amps found in audio interfaces.
The frequency response of this headphone amp is close to flat. And this means you’ll get an accurate and balanced audio signal coming from this interface into your headphones. It also has less to zero noise at all. And overall, they sound excellent.
It is also powerful enough to drive more demanding high impedance headphones with no issues at all.
There is also the MOTU M2 with the same features as the M4, including the same headphone amp. The only difference is the MOTU M2 has fewer input and output channels.
Universal Audio Apollo Twin X Duo
Universal Audio, undoubtedly, makes some of the best audio interfaces on the planet. And that’s not even up for debate.
They are known for making high-end audio interfaces with less to no compromises on quality. And this makes the audio interface’s headphone amp one of the top of the line amps you can find in an audio interface.
There is not much to say about Universal Audio Apollo Twin X Duo (on Amazon). The brand speaks for itself, and I’m sure you’ve probably heard of it too. They are expensive, so you are getting one of the best audio interfaces money can buy.
Do I need a headphone amp if I have an audio interface?
For the most part, you don’t need a headphone amp if you have an audio interface. That’s because most audio interfaces have a headphone amp built into them. However, you may need a headphone amp if the audio interface’s headphone amp cannot drive your headphones or if you need more headphone outputs.
As we’ve already discussed, some audio interfaces don’t have powerful headphone amps to drive high impedance headphones. And if you have a high impedance, you’ll realize that the sound output of your headphone is not loud enough when you plug them in such an audio interface.
So if you are not getting enough volume from your audio interface’s headphone amp, the chances are that you will need a dedicated headphone amp that is powerful enough to drive your headphones.
Also, you will need a headphone amp if you need more headphone outputs than the audio interface can provide. Most audio interfaces have only one headphone output. And a few interfaces provide two headphone outputs.
So if you want more headphone outputs, you will need a multiple channel headphone amp. As I mentioned earlier, the Behringer Powerplay HA8000 headphone amp (on Amazon) is an excellent eight-channel headphone amp for eight people. A less expensive is the Mackie HM-4 headphone amp (also on Amazon) which has four output channels.
Can You Connect a Headphone Amp to Audio Interface?
You can definitely connect a headphone amp to an audio interface. Ideally, you must connect the audio interface’s line output to the headphone amp’s input. But a much simpler way to do this is to connect the audio interface’s headphone output to the dedicated headphone amp’s input with a 1/4″ TRS or RCA cable.
There are many headphone amps available today with several input connections. Many of them have a 1/4″ stereo input or two 1/4″ TS mono inputs, while others feature RCA inputs.
Simply find the right type of audio cable to connect your audio interface’s Line Output to the headphone amp’s input.
However, if the audio interface’s Line Output is hooked up to another device, you can use the headphone output. In this case, you’ll connect the headphone output of the audio interface to the input of your headphone amp with the appropriate audio cable.
Something to note is, you’ll get a much better sound quality using the audio interface’s Line Output than with the headphone output.
Most audio interfaces have a headphone amp. But mostly, they are not as good as dedicated amps. And that’s because audio interface manufacturers compromise a lot on the components used in making audio interfaces to save cost.