What is an audio interface?
How is sound sent from your external microphone to your computer? As we mentioned in our article about choosing a podcast microphone, your microphone records an analog audio signal, and your computer needs to be able to read that signal. The analog audio signal must thus be converted into a digital signal that your computer understands.
While there are some microphones (i.e. USB microphones) that perform this conversion, there are also external devices that help to perform the analog-to-digital conversion.
An audio interface is an external device that helps to perform the analog-to-digital conversion.
An audio interface is basically an external sound card. It converts the analog sound recorded by the microphone into a digital format and sends it to your computer. The signal is normally sent from the audio interface to your computer via USB, Firewire, or Thunderbolt connection. You can then edit your audio tracks in post-production with your favorite digital audio workstation (DAW), or in simple terms, your editing software.
Different audio interfaces also have different numbers of analog inputs. This means that if you have a multi-channel audio interface with multiple microphone inputs, you may be able to connect multiple XLR microphones to your audio interface. If so, you will be able to send each analog input as a separate track to your computer. This means that you can edit each individual track in post-production. Cheers to getting a crisp and polished podcast with some clever post-production edits!
Make sure that your audio interface has enough of the correct inputs for your purpose. There are mic inputs, line inputs, and optical inputs. Manufacturers often count input channels regardless of the input type. Therefore, if you want to use your audio interface with more than one XLR microphone, make sure to check the number of mic inputs before purchasing the audio interface. Please do not forget this!
What is an audio mixer?
If an audio interface is a person that translates dialogue from one language to another, an audio mixer is a person that summarizes the dialogue.
An audio mixer takes different analog audio signals from your inputs and mixes them.
The controls on the mixer will allow you to directly adjust the sound of each microphone (e.g. adjust microphone gain, apply EQ) as you are recording. You will be able to create monitor feeds and headphone mixers to monitor the sound of your recording as it is happening.
Do you need a separate audio interface if you have an audio mixer?
You can get either (A) a mixer with a built-in audio interface, or (B) a mixer and connect it to a separate audio interface.
(A) Mixer with a built-in audio interface
Some audio mixers have built-in audio interfaces. With these, you do not need a standalone audio interface, as the mixer will perform the analog-to-digital conversion for you. You can simply connect your mixer to your computer and start recording.
Can you edit individual tracks in post-production?
Once again, it depends.
Some mixers will only output one stereo track to your computer.
This is generally not good as you will not be able to make isolated adjustments to each voice during post-production.
Some mixers can perform multi-track recording.
Such mixers will record individual microphones as separate tracks to your computer. Although normally more expensive, this is a better bet for you if you want to record on-premise with someone other than yourself and are also looking at doing post-production edits.
(B) Mixer connected to a separate audio interface
Mixers that do not have built-in audio interfaces have to be connected to separate audio interfaces. However, for every input that you record and want to keep as a separate track, you will need a separate cable to connect a mixer to its audio interface. This can not only get messy with multiple cables if you have multiple guests but will also mean that you need an audio interface that has the same number of inputs to connect to. This could thus significantly increase your financial outlay required for your setup.
Should you use an audio interface or an audio mixer?
Are you doing a live broadcast with minimal post-production adjustments?
- If you are recording a live podcast, a mixer will allow you to make adjustments as you record. You can also add music, sound effects, recordings all in real-time. This would not only allow your listeners to hear your full show with all its bells and whistles as you record but also significantly cut down your post-production time.
Are you doing a live broadcast without too many frills?
- Unless you want to make a ton of adjustments or add other sound effects on the fly, a standalone audio interface is more than enough (and you can add a mixer in the future if you decide that your podcast still needs some adjustments in real-time).
Are you recording a non-live podcast?
- An audio interface should be able to properly satisfy your needs, giving you great audio quality that you can tweak via your DAW.
If you record with multiple people in the same space, do you want control of each individual voice track when you edit in post-production?
- If you would like to individually edit the different voices in post-production (assuming that each person has their own microphone, which they should!), you will be looking for a setup that gives you multiple outputs for post-production. You can either go for a multi-channel audio interface or a multi-track audio mixer with a built-in audio interface that allows for multi-track recording (especially for live podcasts).
- If you do not need multiple outputs for post-production, you can still go for an audio interface or a regular audio mixer connected to an external audio interface (especially for live podcasts).
Is budget your main concern?
- Audio interfaces are generally cheaper than audio mixers. Do note that with an audio interface, you will have limited control over real-time adjustments to your audio as you record. This should not be a problem unless you want to include other sounds in your live podcast.
Do you only care about improving the sound quality of your podcast?
- Save yourself the money and trouble of having to learn about the knobs and multitude of adjustments you can make with a mixer and get yourself an audio interface! It is plug and play and quite hassle-free. We love it!
How much knowledge do you have or are willing to acquire in sound and audio engineering?
- Effectively utilizing a mixer requires a great deal of knowledge about sound and audio engineering. If you already have the knowledge or are willing to spend the time to learn more about it, you can consider going for an audio mixer IF your podcast format calls for it. If not… consider saving yourself the hassle and money and get an audio interface instead.
Do you normally record in one location?
- Audio interfaces are generally less bulky as compared to audio mixers, and thus more ideal if you tend to switch locations when you record. Audio interfaces are also normally BUS powered, meaning that they can tap onto electricity from a computer’s USB port, making them very convenient to bring around and use.
Whichever setup you choose, we hope that we have helped make your decision-making process a little bit easier!