The Ultimate Guide to Choosing the Best Audio Interface
With so many choices, how do you choose the best audio interface for your home studio?

The audio interface can be confusing to anyone setting up a home recording studio. You might wonder if you really need one, if it will really make your sound better.
In short, the answer is yes.
What does an audio interface do?
The audio interface is the bridge between the digital sounds within your computer’s recording environment, and the outside world.
Every time you hear what’s coming from your computer, the sound is going through a conversion process. Something, is converting it from digital to analogue.
Likewise, when you record something into a mic, it goes through a conversion process – from analogue to digital. Once digital, it can enter the computer’s recording environment for adding effects, mixing and so on.
But what is the something, that converts analogue to digital, and digital to analogue?
It’s the job of the computer’s sound card.
Why not just use the computer’s sound card?
Technically, you could just use the sound card on your computer to convert analogue to digital.
But in reality you’ll find that the quality is nowhere near good enough. The signal will degrade, introducing a lo-fi quality you might not be looking for!
Enter the audio interface. A hi-fidelity sound card replacement. It just sits on your desk, quietly converting that audio as you need it.

What’s the best audio interface for your studio?
This depends on what you’ll be doing in your studio. You’ll need to decide:
- the connection between interface and computer
- how many inputs and outputs
- what sort of inputs
- quality of the analogue to digital convertors (ADC)
- quality of the pre amps
Interface connections
There’s 3 interface connections to consider. Some audio interfaces have more than one option, giving you more choice if you decide to upgrade your computer down the line.
- USB
You’ll find these on the cheaper interfaces as they have the slowest transfer rate.
- Firewire
These aren’t seen much these days, but hey offer a good transfer rate.
- Thunderbolt
This is a great choice if you can afford it, and if your computer has Thunderbolt connections. It’s much faster than both USB and Firewire.
How many inputs do you need on your audio interface?
Every audio interface has a number of input and output sockets.
Let’s start with the outputs. You’ll probably only need two of these, to connect to your studio monitors. You might want more outputs if you have an extra set of monitors to feed.
Inputs are where sound enters the audio interface. If it’s just you recording, you’ll probably only need 2 inputs. With 2 inputs you can record vocals, or a stereo guitar.
But if you wanted to record a stereo guitar, vocals and a stomp box, all at the same time, you’ll need 4 inputs.
Or if you wanted to record a live band, with drum kit, you’ll need at least 16 inputs. It’s probably better to book a commercial studio for this, as they’ll an acoustically treated live room, and a selection of good mics.
The different types of inputs on an audio interface
While choosing an interface, pay attention to the types of inputs it has. You’ll find a combination of mic, line and optical:
– Mic
These are for plugging microphones directly into. Microphones have a low signal which will be boosted with a preamp. They should also have the option of switching on ‘phantom power’ when using condenser mics.
-Line
These are for higher level signals, like keyboards, mp3 player or the output of an external preamp.
–Optical
Some audio interfaces can accept digital sources, which allow for input expansion

Analogue Digital convertors (ADC) on an audio interface
When recording an external signal, the audio interface converts the sound from analogue to digital. Any audio interface will be a huge improvement to a sound card.
But there’s also varying qualities with sound cards. The more expensive sound cards invest a lot into this conversion process, offering the cleanest signal they can.
Suitable preamps for an audio interface
When using a microphone, the interface will boost the signal with a preamp. Along with the ADC, the preamp will determine the quality of the signal as it reaches your computer.
Some engineers prefer to use separate dedicated preamps to ensure that optimum sound. But it probably wouldn’t be necessary with most quality audio interfaces.
Take a look at the Audient range, or something from Universal Audio if you have budget.
Conclusion
Once you’ve chosen a computer and some DAW software to go with it, the Audio Interface is the next addition. If you’re a solo musician, stick to something simple, like a 2 in, 2 out.
But if you’re planning on recording several sound sources simultaneously, look at an audio interface with more inputs.
While picking up your audio gear, don’t forget to work on the acoustic treatment of your room too – it will make a big difference.
Author: Daren B

Daren studied classical piano and composition at Trinity College of Music, at undergraduate and postgraduate level.
His music has been performed at the Southbank Centre, Tate Modern, and the Courtauld Institute, and broadcast on BBC Radio 3, Radio 4 and countless TV shows, including The Apprentice, Top Gear and Horizon.
Daren is a former lecturer on the BA Music Course at Goldsmiths College, University of London. He currently works in London as a composer and psychotherapist.