What Is An Audio Interface?..And Do You Need One?

Audio Interface.

It’s a bit of a weird name isn’t it?

Not surprising then, that hell of a lot of people don’t what an audio interface actually is.

Let alone what one does!

So let’s not waste time with me dragging out a pointless intro.

What is an audio interface?..

…let’s get to it!…

what is an audio interface in black text on yellow and green diagonally split background

What is an Audio Interface?…and What Does it Do?

Back in the purely analogue era, there was no such thing as an audio interface.

The dawn and rise of the digital age has spawned many new gadgets…

…and the audio interface is one of them!

So what does an audio interface do?

In the most basic terms, it converts an analogue signal into a digital signal.

To add a little more detail:

Microphones capture sound signals from vocals and instruments.

Once captured, the microphone outputs the sound signal as an analogue signal.

But, if this analogue signal is then transferred on to any piece of digital kit, like your computer and production software, it won’t be recognised.

The signal is analogue. The digital kit is…well, it’s digital. 

Quite simply, they speak a different language! 

To solve this problem, you add an audio interface into the set-up, between your mic and your digital device.

The audio interface will then convert the audio signal it receives from the mic, into a digital signal.

The digital signal is then transferred on to your computer, where it will now be recognised.

Is That Everything That an Audio Interface Does?

I’m glad you asked, because it has another big track up its sleeve.

A couple of nano-seconds after converting the analogue signal to a digital signal, and sending it to your computer…

…it can receive the digital signal back…

…this time converting it from digital to analogue!

It then makes this analogue signal available at the interface’s line outputs, ready to send to your studio speakers, headphones, or any other line-level device.

front and back of audio interface to show inputs and outputs
Focusrite Scarlett 2i2 3rd Gen USB Audio Interface

The above image of both the front and back of an audio interface might make it a little easier to visualise the signal journey.

So as you can see, an audio interface provides a super-easy way for musicians and producers to get all of their inputs from vocals, synths, guitars, drums etc. into their Digital Audio Workstation (DAW)…

…and also for being able to hear the results back, almost immediately, through headphones, studio speakers and monitors.

What are the Main Advantages of Using an Audio Interface?

It’s true that if your computer is fitted with a sound card, you already have the capability to convert an audio signal into a digital signal.

But using an audio interface will have a dramatic effect on your sound quality.

The sound quality produced by a sound card compared to an interface is simply incomparable.

So if want to produce decent sound, you have to go with the audio interface.

Also, it’s way easier to use an audio interface due to the multiple inputs and outputs available.

You’re able to plug a mic in, a guitar’s ¼ inch jack in, synth, just about everything. 

Try sticking that lot into your computer! 

How do You Connect an Audio Interface to a Computer?

Most audio interfaces will connect to your computer via a USB or Thunderbolt port.

Most interfaces will work with both Windows and Mac systems.

But, Apple iOS devices often require an adapter.

This is the detail you’ll need to be really thorough about before parting with your cash.

Make sure you read up on your preferred interface devices, so you don’t make an expensive mistake by buying one that won’t play nicely with your computer.

Will an Audio Interface Work with a MIDI Keyboard or MIDI Controller?

Most, but not all, high-end audio interfaces have a MIDI connection.

This will enable you to easily connect a keyboard or DJ controller up to your computer.

But once again, make sure you check the spec’s properly before parting with your cash.

Do You Need an Audio Interface if Using a USB Mic?

Technically no.

USB mic’s have an audio interface built-in.

So you can simply plug your USB mic directly in to your computer’s USB port.

Depending on the quality of your USB mic, you could take a hit on sound quality.

And depending on whether or not it’s just a recording mic, with no headphone or speaker outputs, it may be a bit more hassle than a dedicated audio interface.

Is an Audio Interface the Same as a Sound Card?

Technically yes.

An audio interface and a sound card do the same thing.

They can both turn sound signals from analogue to digital, and back again. 

But a separate, dedicated audio interface will add endless quality to your sound.

And then there’s the hassle factor.

A separate interface makes it easy to hook-up multiple devices, which is not he case with the average computer.   

Choosing the Right Interface

Before you start chucking your money about left-right-and-centre…

here are a few questions to ask yourself about your choice of interface:

  • What connection does your computer have (USB, Thunderbolt, both)?
  • How many mics/instruments do you need to use at any one time?
  • How many outputs for headphones and speakers etc?
  • Do you need features such as MIDI, digital connection inputs and outputs etc?
  • What sort of sound quality does it produce?

Before we wrap this up, lets just take a quick look at that last point…

…Sound Quality

It’s pretty easy when looking in to a totally new device of this type, to forget about possibly the most important function of all.

Your new audio interface is going to become a major part of your set-up.

And it’s going to be carrying out a hugely important function.

Converting your sound signal, and then converting it back again.

The quality of the converter, and the mic preamp, are key to how good your sound is going to be.

Do plenty of research to make sure you are getting the best piece of kit for your budget!

Wrapping it Up!

Not much more to add really.

Hopefully this article has helped clear up what an audio interface actually is…

…and what they do.

Questions about what is an audio interface?..Get in touch!

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