One of the most essential items in your podcasting arsenal is an audio interface.
It’s the only way to get music or your vocal recording from your mic to your laptop.
The type of audio interface you need depends on your needs.
There are so many models in the market, from the affordable M-Audio M-TRACK Duo and Behringer Uphoria UMC202 HD series at less than $ 100 to the more pricier models like the Arturia and Motu M2 audio interfaces clocking in at dizzying heights of $199+. If you can afford them, the Zoom range of handheld recorders also double up as great audio interfaces.
The world has come a long way since the days when you had a large analog mixing desk as the only way to route music to your computer or studio monitors.
I still have over 4 mixers in my studio ranging from the Allen & Heath 22-channel, Behringer 16-channel and Yamaha console panels. I now only use them for live musical performances.
But now that I’m in podcasting, there is no need for them on my studio desk.
What I need is a simple, small audio interface that takes up less than a tenth of the real estate that my bigger mixers used to occupy.
In this article, I’ll briefly describe what an audio interface is, how it works and what you should expect from it.
I’ll then share my top audio interface picks in this post here.
But first, we need to answer the question, “Why use an audio interface in the first place?”
Why Use An Audio Interface?
You need an audio interface because it offers you greater versatility in podcasting.
If you’re using a USB microphone, for example, sooner or later you will realize that it actually limits you.
The problem with using an USB microphone is that you can only connect one mic to your laptop.
At some point, you will realize this isn’t the best way to get the most out of your podcasting.
Suppose you want to record a guest, you will need to share the same USB mic. That doesn’t make for good sound levels, and hence the need to invest in a good audio interface.
An audio interface gives you the following advantages:
- You can use any XLR microphone
- You can use more than one microphone at a time (USB mics allow only one mic to connect)
- The headphone output in a USB interface will sound better and louder than the headphone output of a USB mic or laptop ‘phone jack.
- Still on the ‘headphone output’, the output allows you to directly monitor your signal with zero latency meaning you get very accurate feedback on your real-time recording.
- Most interfaces provide inputs for guitar/bass/keyboards as well as mics.
- Interfaces provide volume control for at least one pair of speakers and some provide multiple headphone and speaker outputs.
"An Audio interface is the easiest way to send an audio signal from your microphone to your computer/laptop."
What Is An Audio Interface?
An Audio interface is the easiest way to send an audio signal from your microphone to your computer/laptop.
It’s a device that receives an analog audio signal (like your voice or instrument) and converts it into a digital signal that your computer can read.
The interface also routes audio from your computer out to your headphones and studio monitors.
An audio interface connects to your laptop or computer via a USB cable.
They range in price, with some like the M-Audio M-track Duo costing as low as $49 and others like the Motu M2 costing $199. The difference in price is because of the quality of the components used within the device like the pre-amps and circuit boards.
Audio interfaces are mostly powered by the laptop you’re using, although some need to be powered by an external power source because it contains a ton of functions, plugins and software bundled within.
The number of inputs/outputs (I.O) that an audio interface contains also determines price.
The more the inputs and outputs, the pricier. The less the inputs and outputs, the more affordable the unit.
There are some single channel audio interfaces below $100 that are really good.
More inputs allow you to record multiple tracks simultaneously, while more outputs allow you to send your audio to multiple audio destinations simultaneously.
If you’re a podcaster who’s interested in recording no more than two microphones at any given time and you have just one pair of speakers, a two-input / two-output audio interface would be ideal.
A good audio interface usually contains the following essential components:
- Microphone preamps
- Audio converters (A/D converter)
- Monitoring section (Headphone output)
- 1 or more XLR (mic) channels
- Gain knob
- Volume knob
- Combo Mic/Line insert inputs
- Main signal output
Microphone Preamps
The most essential component of any audio interface is usually the quality and nature of the microphone preamps.
To understand what a microphone preamp is, we need to explore the sound signal chain process.
When you speak into a mic, you make sound energy that travels from your mouth hitting the microphone where a coil surrounding a magnet converts that sound energy into vibrations that cause electronic impulses. This is what’s referred to as a mic signal, and it tends to be very faint. This is where your mic preamps come in. These are the circuits inside the audio interface that boost the mic signal. The preamps receive the sound source and considerably boost it while detecting and limiting any inherent noise from the actual voice/sound. This is what we call ‘signal-to-noise’ ratio. The next destination is the analog to digital converter ( A/D converter) that converts that line signal into a digital signal that can eventually be read by your computer or laptop.
This is now the line level signal that you can detect and manipulate via your volume knob.
(When you hear a lot of music experts talking about ‘clean sound’ from their interfaces, this is what they are referring to.)
Unfortunately, the preamps in an USB mic are usually too small to do such a complicated task properly.
Hence the need for an audio interface that has bigger and more advanced mic preamps.
In the audio world, Midas preamps are arguably known to be one of the best preamps in the industry, so any audio interface that contains these is bound to be a good interface.
Some audio interfaces are very expensive because they have exceptionally high-quality microphone preamps that boost a mic signal in a clean and pure fashion, with a minimal amount of noise.
However, thanks to the wonders of technology, a lot of affordable audio interfaces on the market these days also have pretty solid microphone preamps that don’t burn a hole in your pocket.
Let’s talk about audio converters now.
Audio converters
You’ll probably see the term supported sample rates on most audio interfaces, along with values such as 44.1 kHz, 88.2 kHz, 96 kHz, 192 kHz, etc.
This is related to how the audio interface can handle converting your captured audio (analog audio) into digital signals in a way that allows your computer to ‘read’ them.
Naturally, the higher the sample rate, the better the audio quality and the bigger the file size.
Audiophiles and professional engineers often pay huge sums of money for interfaces with pristine state-of-the-art converters.
After all, you can have the best microphone, the best microphone preamp, and the best vocalist in the world, but if your audio converters that ultimately turn your recording into a digital signal are low quality, then your resulting audio will also suffer.
Audio converters don’t solely exist on the ‘front end’ when capturing audio—they also exist on the ‘back end’ when digital audio from your computer needs to be converted back to an analog signal, so that your speakers can play it back. Generally, you’ll find that audio interfaces with high-quality audio converters tend to be more expensive.
Monitoring section
Every audio interface has what we call a monitoring section.
This consists of a volume knob, a direct monitoring headphone signal output and an output (or headphone jack).
Usually, the more monitoring options an interface has, the more costly the interface is going to be.
Connector types
Last but not least, it’s important to understand the way an audio interface connects with your computer.
These days, most interfaces come with USB 3 connectors or USB-C connectors.
For most use cases, a standard USB 3 connector should be good enough, but if you need much lower latency (this might come into play if you’re recording multiple inputs simultaneously), then consider going for a connector with a higher bandwidth such as the Thunderbolt connector.
At this point, the main question to answer is whether you should go for an entry-level interface or an advanced level interface.
Let’s chat about entry-level interfaces.
Entry-Level Interfaces
Entry level interfaces usually have two characteristics:
- Price
- Number of input/out channels
Entry-level interfaces tend to be priced at below $100 and normally contain one or two combo XLR/line channel inputs, and support one headphone and a single monitor output.
Behringer and M-Audio are leading the way in producing a range of affordable, top quality audio interfaces in this price bracket.
Here are some good picks:
- Behringer U-Phoria UMC202
- PreSonus AudioBox USB96
- M-Audio M-TRACK Duo
Advanced Level Audio Interfaces
Interfaces at this price generally pack additional mic/line inputs.
A 4 channel audio interface will tend to be more expensive than its 2-channel counterpart. The Behringer Uphoria UMC 404HD is a good example. It’s almost double its UMC 202 HD small brother.
Advanced audio interfaces also tend to have more sophisticated components like higher end mic preamps, onboard DSP, cue mixes and generally higher quality electronics like circuit boards. These devices may be USB, Thunderbolt, or both.
Brands like Motu, UAD, Focusrite Scarlett stand out in this category.
- Focusrite Scarlett 8i6: Provides 2 mic inputs and 4 additional inputs, allowing you to use up to 6 microphones (with your choice of external mic preamps). Includes digital input and output, speaker and headphone control, and even MIDI connections.
- UA Volt 1: The Volt 1 gives you simple 1-in/2-out audio connections. Just plug in a mic or instrument to the front panel. Then connect your speakers or headphones to monitor your audio with no latency.
- UA Volt II: This is the perfect USB audio interface for creative collaborators — from musicians and songwriters to livestreamers and podcasters — who want to easily record audio with legendary studio sound.
- UAD Apollo Twin MKII: Provides 2 mic/line inputs and 1 guitar/bass DI input. Comes with onboard DSP and includes plugins of classic compressors, equalizers, reverb. and amp simulators.
Which Audio Interface Is Right For Me?
Most of the audio interfaces in the market work great.
They are designed to read most digital audio workstations (DAW’s) right out of the box making it a breeze to get started. Their plug-and-play feature means that you don’t need advanced technical knowledge to get the most out of your unit.
My recommendation would be to choose a 2-channel or 4-channel interface because that way you always have the option to record multiple guests at a go. If you only have a 1-channel device, you’re stuck.
Also, select one that comes with bundled software.
Resist the temptation to go cheap.
These types of units usually compromise the most important component of any audio interface - the mic preamps. If you don’t have much budget, go for a reputable brand like Behringer or M-Audio. If you have budget, the Focusrite Scarlett 2i2 is your best pick.
In Summary
Whether you’re a podcaster or a music producer, an audio interface is the most essential tool in your audio gear arsenal.