So, you want a new audio interface, eh? It’s not like the old days when there were only a few options. Now, there are a bunch of brands such as Apogee Electronics, Antelope, Audient, Focusrite, MOTU, PreSonus, Universal Audio, and Waves, and each manufacturer normally has several interfaces in its product line. You don’t want to buy something that will be insufficient for the work you do, nor do you want to spend too much money on something that is far more than you need. So, how do you pick one? It all starts with asking yourself the right questions.
How Will You Connect It to Your Computer?
The answer to this question will greatly narrow down your list of options. Common types of connections employed by audio interfaces include USB 2.0/3.0/Type-C, FireWire 400/800, Thunderbolt 1/2/3, and RJ45 Ethernet. There is another one called DigiLink, but it’s proprietary to Avid Pro Tools HD PCI cards and will be excluded from this article. Clearly, you need to know or figure out what ports your computer offers. If your computer is blessed with more than one of the listed connection types, you should make your choice knowing some basic information about them.
USB interfaces such as this Focusrite Scarlett 2i2 are usually the most affordable and USB is the most compatible with a wide variety of computers. USB Type-C supports faster data-transfer rates than USB 3.0, which supports faster data-transfer rates than USB 2.0.
Expect FireWire interfaces like this MOTU Traveler-mk3 to be less affordable than USB interfaces. FireWire is seldom found on new computers, but is common on older machines. FireWire’s main advantage is that it’s a separate bus from USB, so it won’t be impacted by USB traffic. FireWire 800 is faster than FireWire 400 and uses a different connector. Some FireWire interfaces like this MOTU 828mk3 Hybrid also feature USB connectivity for expanded computer compatibility.
Thunderbolt™ interfaces such as the Apogee Electronics Element 88 and the PreSonus Quantum are often more expensive than models equipped with only USB or FireWire. Thunderbolt is more common than FireWire on relatively new computers, but it’s not as common as USB. Thunderbolt supports faster speeds than FireWire or USB and unlike USB, it supports daisy-chaining devices.
Ethernet interfaces like the Waves DiGiGrid D are usually in same cost range as Thunderbolt interfaces, but are less plentiful. They’re often intended for use in networked audio configurations such as broadcast and live stage applications. Ethernet was a standard connector on computers for many years. However, it’s not surprising that manufacturers have been excluding it from entry-level and low-budget models over the last few years.
Do You Need the Interface for Recording, Mixing, or Both?
If the interface is to be used for recording, what sources will you be dealing with—analog microphones and instruments, analog line level, or digital signals? For analog microphones and instruments, the interface should offer XLR and 1/4" TS inputs and mic preamps. For analog line level sources, the interface can do without mic preamps, but should have line inputs, whether they are 1/4" TRS, DB25, or XLR jacks. For digital signals, you’d need an interface with AES/EBU, S/PDIF, ADAT optical, or MADI—depending on what equipment you plan to connect.
If the interface is to be used for mixing, what mixing style do you need it to serve—ITB (in the box) or sending out to analog gear? For ITB mixing, the interface only needs a few outputs, such as a headphone jack and stereo analog outputs to feed speakers. However, if you’ll be mixing through analog gear, the interface should have eight or more analog outputs to enable connection to several outboard compressors and EQs or multiple channels of a summing mixer or console.
What Extras Do You Need?
It’s easy to overlook “lower-priority” features such as MIDI ports and synchronization connectivity. For many users, a single MIDI input and output is fine. Don’t assume that every interface has MIDI I/O; some forego it to reduce cost.
Synchronization needs may include word clock via BNC, SMPTE timecode via 1/4" phone jacks, or MIDI timecode (MTC) via MIDI ports. Some interfaces will offer such connectivity, but often with only input or output jacks rather than with both.
Consider other functions such as built-in talkback, monitor controls, and remote control. Maybe you don’t use them yet, but incorporating them into your workflow could improve your day-to-day audio operations.
Do You Need the Interface to Power Plug-Ins?
Some audio interfaces have hardware DSP chips that can power specific plug-ins. These DSP-powered plug-ins will not burden your CPU, but will only be available via the audio interface. So, if you mercilessly break the interface, you can’t access the DSP-powered plug-ins. Audio interfaces such as the Universal Audio Apollo 8p and the Antelope Zen Studio+ offer mic preamps, line inputs and outputs, hardware-powered plug-ins, and more. Note that manufacturers of interfaces with hardware-based plug-in processing do not give away this power for free. More money gets you more power!
Don’t Get Distracted
With so many interfaces on the market and many of them with strikingly similar feature sets, it’s important to establish some audio priorities. Factors such as color and size are inconsequential in the grand scheme of things. When it comes to interface performance, it’s tempting to initiate a battle of the specifications to choose a worthy winner. However, better specs don’t always translate to audible differences. For example, imagine that interface A has a dynamic range of 123 dB, while interface B’s dynamic range is a massive 124 dB. Is that 1 dB difference going to blow you away? No. Now, I’m not implying that performance specs are unimportant; I’m stating that you must think realistically when comparing them.
So, what things do matter in a major way? Sufficient inputs and outputs, robust functions, ease of use, and low latency are the elements you should give the highest priority.
Common Scenarios
Here are a couple of scenarios widely encountered around the world and an example of an interface that would meet the proposed needs.
Scenario #1:
Production computer with USB connectivity, small vocal/instrument recording sessions (up to two mics at a time), mixing in the box with speakers and headphones
Interface Solution:
Scenario #2:
Studio computer with Thunderbolt connectivity, larger recording sessions with several live instruments (up to 16 mics at a time), mixing with some analog outboard gear, medium plug-in use
Interface Solution:
Conclusion
As old-fashioned as it seems, make a list of what you need. Yes, make a little checklist of the things you need in an audio interface. As you begin looking at different products, create another list—a “Maybe or Definitely Not” list. If you look at three interfaces that don’t coincide with your needs, add them to the “Definitely Not” category. If you find four interfaces that would work for your situation, put them in the “Maybe” category. This will help you avoid looking at the same products multiple times and keep track of how many matches you’ve discovered. Also, talk to other people, ask questions, and get their opinions.
So, what audio interfaces are you considering?
