Audio Interface vs Mixer - What is the Difference?
Right now we’re going to look at the key differences between an audio interface and a mixer. Which one is right for your home recording studio? If you’re confused about standalone mixing consoles, USB mixes, and USB audio interfaces in general, then hopefully this will help you out.
So let’s crack on with the difference between an audio interface and a mixer. I will cover the absolute basics here. Let’s start with the standalone audio interface. Now these come in many shapes, sizes and formats, from a simple two-channel interface for iPad up to multi-channel beasts that allow you to record multiple audio sources. The Focusrite 4i4 is fairly typical. So let’s have a look in detail. The key purpose of an audio interface is to allow you to make high quality recordings on your computer or mobile device. Another one has four audio inputs. The two on the front are multi-format so you can plug in microphones or instruments like guitar, or electric violin, or line level sources like a keyboard. You see these inputs have separate gain controls so you can adjust the level of the signal you’re recording as these two inputs have built-in preamps.
Now on the rear, there are two additional line level inputs. These don’t have any gain adjustment on the interface. They’re at a fixed level. Now, apart from that, there is very little else on this interface. You can control the volume of the output for the headphones and speakers. There’s a phantom power switch if you’re plugging in condenser mics. This audio interface is ideal for recording clean signals into your recording software, and then you can add reverb, delay, compression, and other effects within the software and create your final mix. There is no effects processing at all on the interface. The only thing you can really adjust is the recording level where that’s available.
Another key thing you should note about this typical audio interface is you can record each input on a separate track within your door simultaneously. So if you want your vocal on one track, guitar on another, and maybe a keyboard on another track, you can easily do this. All you need to do is create tracks in your recording software, arm them for recording, choose the inputs, then start recording and play. Each track will capture the individual audio source from the input you have chosen. Now with this interface, you can record four things at the same time on separate tracks. On an interface like the Scarlett 18i20, you can get 18 inputs and 20 outputs in your door, so you’ve got mega multi-track recording capability, and that is what an audio interface is really good for.
Now, let’s take a look at the standalone mixing console. So this Yamaha MG06 is about as simple as you can get. Here, you can connect up to four separate audio sources, two mic or line inputs with gain, and then two additional sets of line inputs, either mono or stereo. Again, each with a separate gain control. Now, even on this simple mixing console, you have the opportunity to adjust the level of the high and low frequencies on the first two channels. So it’s got a very simple EQ. You can also get an effects version of this mixing console that has built-in effects, so you can also add reverb or delay. Move up to the big brother, Yamaha MG10, and you’ll see there are more channels, and you now have the ability to add compression, more complex EQ, panning, et cetera, all on the mixing console.
So what all these mixers have in common is that the output of the mixer is stereo. It is a stereo mix of your audio sources. Your mics, your instruments, et cetera, all combined with all those settings already applied. And that is the key purpose of these kinds of standalone mixers. You can combine different sound sources, adjust the levels, adjust the signal, add effects, adjust the EQ, then output the final result as one stereo stream.
These particular mixers are not USB mixers, so they do not connect directly to your computer or mobile device in any way. They have no built-in interface. So to record on your computer, you have to combine them with an audio interface. That’s quite simple. You just take the left and right outputs from the mixer, connect them to the left and right line inputs on your audio interface, then you can record the output of the mixer in your recording software.
However, you will be recording the stereo mix on one stereo track. You will not be able to capture each instrument on a separate track at the same time. If you want to record instruments separately, you will have to play them one at a time and record them one after the other to get the separate sounds and then mix them after. It is possible to combine the audio interface and the standalone mixing console in one unit, because many mixers you can buy are, in fact, USB mixers.
So for example, the Behringer X1204USB. Now this mix has lots of inputs for various audio sources, you can connect mics, line level sources, and so on. It has built-in effects. It’s got EQ and panning, and this Behringer mixer can operate as a standalone mixer, too. Do beware that not all USB mixers work as standalone mixers, so if that’s important to you, make sure that you look for that feature. But this Behringer mixer also has the benefit of incorporating a built-in USB audio interface. And this is where you need to be careful, because yes, you can connect it directly to your computer via USB, and you can record the output of the mixer in your recording software without any other equipment, or you could stream it live if you wanted to do live streams, but you can only record or stream the stereo mix.
You cannot separate each audio source onto different tracks in your door and record at the same time with this USB mixer. Another difference to remember is you’ll not just be recording the pure signals from your audio sources, but the signals will already have had EQ and effects applied. So much of the work you do with your USB mixing will be in adjusting the signal path on the actual mixer using the hardware controls, then recording or streaming the stereo output. So it’s great for a live stream. It’s a different workflow, and we’ll have a look in a minute at which approach might be best for you. With the audio interface, you record your audio signals on separate tracks, then process and mix the sounds in software. With the USB mixer we just looked at, you set up the levels, effects, EQ, panning, then record the result as a stereo file. But for completeness, let’s compare what we’ve looked at so far with something like the Soundcraft Signature 12MTK USB interface mixer. Now, if you look at the blurb on the box of that one, it says, “This is a high-performance 12-input mixer with onboard effects and multi-track USB recording and playback, with a 14-in/12-out ultra-low latency USB playback and recording interface.” In other simpler words, you have all the benefits of the mixing console. You’ve got the effects and signal processing and the ability to connect and mix multiple instruments and sound sources, plus you have the benefits of the multichannel audio interface in that you can record each sound source on a separate track in your door at the same time.
However, this does come at a price. So audio interface, mixer, USB mixer, which is the right device for you? This is going to depend really on two main things. Your budget, obviously, and what you most want to achieve in your recording studio. If you want to make high quality recordings on your computer or mobile device and then refine them in your door, maybe for a podcast, YouTube voiceover, making simple high quality recordings with your instruments, then an audio interface will be ideal. If you’re more interested in live performance or live streaming, then the USB mixer might be a better option. This will allow you to get all your signals set up, and adjust all the sounds and mix them, and then simply stream the stereo output to Facebook Live, YouTube Live, wherever else you want to perform. And you should also be able to use the mixer as a standalone device too, for live work, away from your computer or mobile device. But as I said earlier, be careful, because there are some that are USB-only, and you have to run them through a computer.
Now, another option is a crossover solution like mine, where you mainly use an audio interface, but when you want to record or mix additional audio sources, you can use a standalone mixing console, like my little Yamaha, that you then output to your audio interface. This does mean you have to have two separate devices. I find it’s quite flexible. It’s how you want to work. And finally, the multi-channel mixer with built-in interface is obviously going to give you the best of all worlds. You can use it to create a stereo mix for live streaming, and also use it as a multi-channel interface to record your separate audio tracks. However, two problems with this approach are budget, because these mixers are not cheap, they’re not an entry level price, and also they’re big. So it might be that if you want more portability, then they’re not appropriate for you, or maybe you haven’t got much room in your home studio. The beauty of an audio interface is it’s usually smaller and more portable, although if you buy one of the big 18-channel beasts, that’s not gonna be the case.
Well, this has been a very quick look at the differences between audio interfaces and mixers. Thanks for reading.
Focusrite Scarlett 4i4 (3rd Gen)
USB Audio Interface with Pro Tools | First