3. The Audio Interface
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3.1 What is an Audio Interface?
- What does it do, and do I need one?.
The Audio interface is the 2nd most important part of your studio, after the computer. Though you can go without one for quite some time if all your work is sample based, it's mandatory if you want to record with a microphone. Without the Audio Interface, there is nowhere to plug a microphone or a guitar into a computer.
An audio interface contains all of the professional style audio connections like:
Microphone AKA - XLR connector
and guitar/ instrument AKA - ¼ inch connector
These connector types aren't common in the consumer world, but are almost the only type of connectors professionals use. An audio interface is also how we can control the volume of our headphones and speakers. It's essentially an external audio card for your computer.
Some Audio Interfaces connect via USB, some by Thunderbolt or even firewire. This will be an important spec to pay attention to because if your computer doesn't have that style of connection type, then you might as well have wasted your money. The interface won't work if we can't plug it into the computer!
An audio interface allows us to connect microphones and instruments to our computer, as well as control the volume of our speakers for audio playback. It also takes a load off the computer so it doesn't have to work so hard when processing audio.
The sound card that comes built into your computer won't provide you with studio grade audio quality, but a decent interface will.
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3.2 Choosing the Right Audio Interface
- Key factors (e.g. number of inputs/outputs, connectivity type).
As we already discussed, some audio interfaces use different connection types like USB, thunderbolt or firewire. They also come in different input and output counts. An input is where you would plug in a microphone. The output is where you would connect a speaker. One pair of speakers will have 2 outputs, a Left and a Right. If you had 2 sets of speakers, you’d want 4 outputs.
If you are only recording vocals, you’ll only need 1 microphone input.
If you’re planning on recording bands, you might look at up to 8 or 16 inputs for different combinations of microphones and instruments.
The base recommendation is always 2 inputs and 2 outputs. So at a bare minimum we can record 1 mic and 1 guitar while playing it on the speakers too. This would be considered a 2x2 i/o or 2 in/ 2 out. We’ll begin to see a lot of “i/o” around. This stands for In & Out (i/o). 16i8o would be 16 ins and 8 outs. A 4x8 would be 4 ins and 8 outs. Pretty straight forward right?
Long story short, your i/o is dictated by how many things you want to simultaneously record. If you’re planning on making Electronic music and not planning on recording vocals or instruments at all, a 2x2 will last you many years. More often than not, you’ll outgrow your computer's computing power before you need a new interface.
The audio interface is how you connect microphones as well as instruments like guitars and keyboards to the computer in order to get them into your DAW. It acts as the main volume knob for both headphones and speakers. It also supplies 48 Volts (phantom power) to condenser microphones which require power to operate. We’ll touch on more of that later. 👻
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3.3 Connecting the Audio Interface
- Instructions on connecting the audio interface to a computer.
Windows
Mac
An audio interface shows up as an audio device in your computer's sound settings. If you’ve ever connected headphones or a bluetooth speaker to a computer, you’ve already messed around with “selecting an audio device for playback”. Remember, an audio interface is both for recording audio (microphone) and playback (speakers).
After you connect the audio interface to your computer, you’ll want to select the interface as both the primary microphone input, as well as the primary speaker output for the whole computer. This tells the computer that when you listen to music, you want it to channel through the i/o of the interface. Regardless of the DAW you’ve chosen, this option will be located in the preferences/ settings of the DAW.
You’ll also want to tell the DAW to look for your audio interface as its primary sound card as well. This will allow the DAW to hear the audio being picked up by the microphone. As well as tell the DAW to play all the sound through the interface and into your speakers or headphones. I’m hoping you’re starting to pick up on why the interface is important. Without it, we really can't record anything.
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Interface/ Audio Device settings in common DAWs
FL Studio:
Ableton :
Logic:
Pro Tools:
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- Installing drivers if necessary.
Not all, but most audio interfaces come with their own software in order to configure it. Not to worry though it's free with the device! Some interfaces even come with a free version of Ableton to help get you started! A lot of music hardware comes with software so don't toss the box without checking for goodies!
Some audio interfaces have drivers or applications that need to be installed before it will communicate with your computer or with programs like a DAW. Others are plug and play, meaning no downloads needed, it just works. Some audio interfaces like the UA Apollo Twin X come with a full on mixing console software that pairs with your DAW for even more control and processing. Make sure you read the instructions that come with your interface. In the intermediate courses we’ll get into why some interfaces are $199 (Scarlett 2i2) and others are $1,499 (UA Apollo Twin X) but they’re both 2x2 interfaces.
For now, there isn't a reason to get the most expensive gear. If you’re blessed with deep pockets, by all means buy the best. But if you’re just getting started and you’re determined to get into audio. A simple Scarlett 2i2 for $199 will be your best friend for years. I started with a Presonus Audio Box i2 and if I had to start all over with less than $200 in my pocket, that's exactly what I would get again.
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- In summary
The audio interface is our main input and output device. It allows us to connect a microphone or an instrument to our computer and record it into our DAW. Without an interface we wouldn't be able to record instruments or power microphones that need 48v phantom power. The audio interface also allows us to control the volume level of our speakers as well as our headphones.
Audio interfaces come in multiple input and output configurations. With the amount of inputs being dependent on how many microphones / instruments you want to record simultaneously. The amount of outputs is dependent on how many speakers / playback devices you want to connect to. Remembering that each speaker requires its own output. Two speakers = Two outputs. One for Left and one for Right.
(note: if you want to record but can't afford both an audio interface and a microphone, getting a decent USB mic will work as well. Though I do recommend getting the interface now and eventually getting the mic later allowing for more growth in the long run. Because eventually, you’ll grow out of the USB mic and still need an interface for a better quality mic. Do what you can with what you have. There is no wrong way to start, and there is no wrong way to learn.)
_________________________________________________________________- A few 2 input interfaces options
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PreSonus AudioBox iTwo
(discontinued but posted for reference, the Scarlett 2i2 absolutely dominated the 2 in 2 out market)
https://www.presonus.com/products/AudioBox-iTwo
A 2-in/2-out USB audio interface compatible with Mac, PC, and iOS devices. It features two combo mic/instrument inputs, MIDI I/O, and comes bundled with Studio One Artist DAW software. Its portability and solid build make it ideal for mobile recording setups.
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Focusrite Scarlett 2i2 4th Gen
https://focusrite.com/products/scarlett-2i2
A compact and user-friendly interface with two inputs and two outputs, offering excellent preamps and low-latency performance. Ideal for home recording setups.
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Behringer U-Phoria UMC204HD
https://www.behringer.com/product.html?modelCode=0805-AAS
An affordable option that doesn't compromise on quality, featuring MIDAS preamps and versatile I/O capabilities, making it great for budget-conscious users.
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MOTU M2
https://motu.com/en-us/products/m-series/m2/
Offers excellent audio quality with ultra-low latency, featuring two inputs and two outputs, along with a full-color LCD for metering.
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Universal Audio Apollo Twin X
https://www.uaudio.com/audio-interfaces/apollo-twin-x.html?srsltid=AfmBOooA5QEqM5cqDizSzUQuA_fWbjlS5TFZPTCzg84QDRFmIFTFLF7N
A premium interface with real-time UAD processing, high-quality preamps, and a sleek design, perfect for professionals seeking top-tier performance.
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Focusrite Red 16Line
https://focusrite.com/products/red-16line
The Focusrite Red 16Line provides 16 line inputs and outputs, along with dual Thunderbolt 3 ports and Pro Tools | HD compatibility, delivering high-resolution audio conversion and low-latency performance.
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Universal Audio Apollo x16
https://www.uaudio.com/audio-interfaces/apollo-x16.html
The Universal Audio Apollo x16 features 16 line inputs and outputs, elite-class A/D and D/A conversion, HEXA Core UAD plug-in processing, and supports up to 9.1.6 immersive audio formats, making it ideal for professional studios.
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RME Fireface UFX+
https://www.rme-audio.de/fireface-ufx.html
The RME Fireface UFX+ offers 12 analog inputs and outputs, along with extensive digital I/O options, including MADI, ADAT, and AES/EBU, providing up to 94 channels of I/O and exceptional audio quality.