An audio interface is an essential kit in the studio setup, especially if you spend time making music on a Mac or PC. The best audio interface will ensure you get high-quality audio both in and out of the computer. Additionally, it will also allow you to connect other important studio instruments and gear during the recording sessions.
There are a lot of audio interfaces in the market today, all providing different features and designs to grab your attention. So, how do you know the best audio interface that matches your and your studio's needs?
The guide below will provide you all the information you need to know about audio interfaces before you can buy one. Additionally, we will recommend some of the best audio interfaces you can buy, with options ranging from entry-level USB audio interfaces to multi-input Thunderbolt options.
- What is an Audio Interface?
- How Do Audio Interfaces Work?
- What is the Best Audio Interface?
- 1. Behringer U-Phoria UM2 Audio Interface
- 2. PreSonus AudioBox USB 96 2x2 USB Audio Interface
- 3. Focusrite Scarlett 2i2 (2nd Gen) USB Audio Interface
- 4. Focusrite Scarlett 18i20 (2nd Gen) USB Audio Interface with Pro Tools
- 5. Universal Audio Apollo Twin MkII Heritage Edition
- What is Inside an Audio Interface?
- What Do You Need Consider Before Buying the Best Audio Interface?
- What Makes the Best Audio Interface Cost Vary?
- How Many Mic Preamps and Instrument inputs Do You Need?
- Understanding the Digital Signal Processing Software
- Frequently Asked Questions (FAQs) on Audio Interfaces
What is an Audio Interface?
An audio interface is a piece of equipment that allows recording of the analog signal, converting them to a digital signal, and later transporting them to your computer. In addition, it allows you to do your post-processing work, such as mastering and mixing.
Ideally, an audio interface is used for sound recording and production in the telecommunication and entertainment industries. It is one of the main two sound devices that do a bare minimum in capturing the audio. The other device is a microphone or an instrument with an output jack.
You may need a microphone added to your interface if you're recording a real-world source like an acoustic guitar, saxophone, or your voice. The mics come in handy to record the soundwaves then convert them to electricity. They are plugged into the interface, but you can otherwise plug a digital or electrical instrument to achieve similar functions.
How Do Audio Interfaces Work?
The audio interface receives a signal from the instrument or microphone, digitizes it before it is sent to your computer. This is done using an analog-digital converter with a pulse code modulation. It is a more high-quality and convenient option than using the old method of recording to cassette tape or magnetic tape.
Now that you have a glimpse of what audio interfaces are and how they work, here are the five best audio interfaces available today.
What is the Best Audio Interface?
1. Behringer U-Phoria UM2 Audio Interface
- 2x2 USB audio interface for recording microphones and instruments
- Audiophile 48 kHz resolution for professional audio quality. Maximum sampling rate: 48 kHz
- Compatible with popular recording software, including Avid pro tools, Ableton live,...
- Streams 2 inputs / 2 outputs with ultra-low latency to your computer, supporting Mac OS X...
- State-of-the-art, +48 V-powered Xenyx Mic Preamp comparable to stand-alone boutique...
The Behringer U-Phoria Audio Interface 1x XLR/TRS 1x 1/4" 2X RCA USB is one of the cheapest audio interfaces that you can buy without sacrificing quality. It comes with a black and silver casing that is made from top-quality plastic.
It offers two inputs on the front side, where one of them is an XLR / TRS ¼ inch (6.35 mm) combo, and the other one is ¼ inch (6.35 mm). The XLR is used for connecting a professional microphone while a TRS for electronic instruments like guitars, keyboards, etc. This is a low latency device that comes in handy for someone who is looking to record lots of guitars and vocals.
The inputs have two associated LEDs that are located to the right of each of them. The green one indicates when a signal is detected, while the red one will show when the signal is clipping. The other two LEDs, the orange, will tell you when the device is on, and the red (+48V) will indicate if the phantom power is on.
It is powered by USB so you can plug it into your computer and you won't need to use any other source of power. So while it may not be having flexibility and the features of other audio interfaces, the model seems to be outdoing itself for the price.
2. PreSonus AudioBox USB 96 2x2 USB Audio Interface
- Value-packed 2-channel USB 2.0 interface for personal and portable recording.
- 2 high-quality Class-A mic preamps make it easy to get a great sound.
- 2 high-headroom instrument inputs to record guitar, bass, and your favorite line-level...
- Studio-grade converters allow for up to 24-bit/96 kHz recording and playback.
- Comes with over $1000 worth of recording software including Studio One Artist, Ableton...
The PreSonus AudioBox USB 96 2x2 USB Audio Interface features a 2-channel 24-bit/96kHz recording with two mic inputs that offer 60dB of gain that double up as 1/4″ inputs via combo jacks. The model also offers stereo main outs, a headphone jack, and switchable +48v phantom power.
This compact USB 2.0 interface provides an amazing way to get into high-resolution mobile recording. Additionally, since it operates on USB bus power and comes in size smaller than 2" x 6", it is easily portable, and you won't have to carry a power supply around.
It provides MIDI in/out, includes Studio One Artist DAW software, and also comes with a 6GB of bonus third-party content that includes the Studio Magic Plug-ins Suite. In addition, it is compatible with PC or Mac operating systems.
The PreSonus AudioBox USB 96 2x2 USB Interface features all-metal construction and small size. This interface is perfect for recording DI electric guitar or piano and also a great choice for recording on the go. Any songwriter, singer, or someone who won't be recording more than two items at once should consider this option.
3. Focusrite Scarlett 2i2 (2nd Gen) USB Audio Interface
- Two natural-sounding Scarlett mic preamps with plenty of even gain; two instrument inputs,...
- Class-leading conversion and sample rates up to 192kHz / 24 bit; super-low roundtrip...
- LIMITED TIME OFFER: FREE Venomode DeeQ, Maximal 2, and Pivot, plug-ins upon registration...
- Includes Pro Tools | First Focusrite Creative Pack and Ableton Live Lite, Softube Time and...
- Compatible with Windows 7 and higher, and Mac OS X 10.10 and higher. Frequency response -...
The Focusrite Scarlett 2i2 (2nd Gen) USB Interface with Pro Tools is another great two-channel interface. It features two Focusrite preamps with additional air functionality to allow you to get different sound types from the same preamps.
The Scarlett 2i2 comes in handy to find the right vocal and guitar tone. The 2i2’s inputs will accept an XLR or ¼-inch cable too. In addition, this Scarlett 2i2 interface features two stereo outputs for headphone output and a pair of monitors as well.
Additionally, the Focusrite Scarlett 2i2 (2nd Gen) USB Interface boasts an amazing sound quality in a portable and sleek package. So, if you're in search of versatile and great preamps on a budget or a portable interface, then you should consider getting this interface.
Another great feature for the Scarlett 2i2 is the wired analog protection circuit for outputs and inputs to protect the interface from power surges that could potentially damage it. It also has an extremely low latency that makes monitoring the vocals and instruments in real-time an easy task.
4. Focusrite Scarlett 18i20 (2nd Gen) USB Audio Interface with Pro Tools
- Eight natural-sounding Scarlett mic preamps with plenty of even gain; two newly-designed...
- Class-leading conversion and sample rates up to 192kHz / 24 bit; Super-low roundtrip...
- Frequency response - 20 Hz - 20 kHz ± 0.1dB. Supported Sample Rates: 44.1 kHz, 48 kHz,...
- Includes Pro Tools | First Focusrite Creative Pack and Ableton Live Lite, Softube Time and...
- LIMITED TIME OFFER: FREE Klevgrand DAW Cassette upon registration and download.
For a good reason, the Focusrite Scarlett 18i20 (2nd Gen) USB Interface with Pro Tools is one of the most popular interfaces used in project studios. This is because it boasts a wide range of features and the ability to be expanded, which can keep it operating for a long time.
This interface has eight XLR/¼” inputs for large full-band sessions or tracking drums. Just like other Scarlett devices, this model also features Focusrite’s “Air” technology. Moreover, it features a pad to help lower the gain in loud sound sources.
It also has S/PDIF and optical connections that make it simpler to connect the external preamps instruments or affect the units, which comes in handy if you require more inputs. You also get tine line-outs on the output that include two for a pair of monitors.
The two headphone jacks are found on the out and front optical ports. You also get a talkback function word clock out, MIDI in and out, and monitoring tools. This is a full-featured interface that is not only perfect for a project studio but also for someone looking to record a full band or a full drum set.
5. Universal Audio Apollo Twin MkII Heritage Edition
- A special edition of UA's acclaimed Apollo Twin MkII interface — with a premium suite of...
- Next-generation Apollo A/D and D/A conversion and 2 Unison mic preamps that offer stunning...
- 2 Unison mic preamps offer stunning models of classic tube and transformer-based mic...
- UAD DUO Core Processing for tracking through vintage compressors, EQs, tape machines, mic...
- Produce with LUNA Recording System — a fully-integrated recording application made for...
With a desktop format of 2-in/-6-out interface with 24-bit/192kHz capabilities, the Universal Audio Apollo Twin MkII Heritage Edition is almost indistinguishable from the original, except it is black instead of silver. It is a musically empowering hardware and software that helps elevate the project and home studios to professional quality.
This model connects to your PC and Mac using Thunderbolt but needs to be powered from the wall. Both the front edge and back panel house the inputs and outputs, while its top panel will center on an oversized knob. It has a built-in UAD processing that allows you to enjoy analog, warm and rich sounds.
It includes a DSP box to power the UAD plugin effects that you can choose from Solo, Quad, and Duo options. In addition, it comes with impressive Unison preamps fed by the Hi-Z ins and Mic/Line. These functions allow a gradual expansion subset of the UA's s hardware emulation plugins so that they can be inserted directly into every input path.
The Universal Audio Apollo Twin MkII Heritage Edition also comes with a built-in microphone to use in your home studio or even project studios when you want to talk to someone in the recording booth without the need of grabbing a microphone. You also get the Realtime Analog plugin bundle from UAD, including delay and reverb plugins, some EQs and compressors, channel strips, guitar amp, and emulators.
What is Inside an Audio Interface?
While we don't need to know what is in most of the devices before we can use them, when it comes to a recording interface, understanding what is happening inside will help visualize the signal path. For example, knowing what's inside becomes even more important if you start using hardware equalizers and compressors.
The interface will feature a combination of the input types such as;
- A microphone that has a balanced XLR cable towards the preamplifier.
- The instrument has an unbalanced TRS/TS cable that bypasses the mic preamp
- MIDI provides digital information about how the instrument has been played.
In the past, some interfaces had separate TRS and TS high impedance inputs for electronic equipment and separate XLR inputs for microphones. Nowadays, most interfaces combine the two in a single output.
Microphones need to pass through a preamplifier since their electrical signal is much smaller in amplitude than that of an electronic instrument. Therefore, the XLR input for mics runs its signals through the preamplifier, while the Hi-Z (high impedance) input for the instrument will bypass it.
Moreover, audio interfaces will feature three types of outputs including;
- Headphone outputs help in personal monitoring with output on the front
- Monitors for room monitoring through the speakers with master outputs on the back
- Interface cable for communicating back and forth with the computer.
The lower-end audio interface will only come with one headphone output with volume control, while the expensive options will feature two or more headphone outputs. There are also some headphone amplifiers that provide outputs for all the band members.
The studio monitors may not refer to your computer screen but instead to your speakers. Most interfaces use XLR cables that master the output to your monitors, but some will use TRS cables. All these types of cables and adapters are available to ensure that interface works with your monitors.
What Do You Need Consider Before Buying the Best Audio Interface?
1. Inputs and Outputs
When deciding on the best audio interface, you need to consider the type and number of inputs and outputs you need. For example, if you only want to plug in one instrument or microphone at a time or if you're a solo producer who produces most of the sounds inside the computer, then one or two inputs are enough.
If you're hoping to record a live band, you need to think about more inputs. Multiple outputs are also useful if you're planning to set up headphone mixes or send audio somewhere for further processing. On most audio interfaces, you will find both 1/4 inch inputs and XLR combined into combo connectors to allow you to plug guitars, mics, synths, etc., in the same input.
Most interfaces also have a phantom power option which is required especially if you want to use specific microphones. Some also have MIDI I/O that could save you from buying a separate interface for the external MIDI.
However, if you're planning to use a MIDI keyboard only, you can plug it into your computer's USB ports which means MIDI I/O might not be an essential requirement.
Audio interfaces will mostly run over the Thunderbolt or USB, and you need to ensure that the type you choose is compatible with connections on the computer. Nowadays, more interfaces with USB-C connectors have hit the market, but this is not a big issue if the machine has older USB because there are a lot of adapter or cable options out there.
Furthermore, most interfaces are class-compliant, which means once you plug them in, you can begin using them right away. Here are the main types of connectors used in audio interfaces;
- USB- This is the most common interface connector that can be plugged directly into a USB 2.0 or 3.0 socket. It is compatible with PCs and Macs.
- Thunderbolt- It is the second most common connector that is preferred because of its fast speeds and compatibility with most Macs
- Firewire- This is an older Mac connector that in the past has the fastest transfer speeds but not as Thunderbolt.
- PCIe- This is a different connector type used on internal interfaces which connect directly to the motherboard. Although it is the most expensive, it is also the most reliable, very fast, and has low latency.
Bus powering is also another feature you should look out for when it comes to connectivity. It means that you won't have to plug the main power supply into the interface.
It is important to check to see if the interface has iOS compatibility to ensure that you can make music with your iPhone or iPad if it is something that is important to you.
3. Low latency
Another factor worth taking into account is the low latency recording. Most contemporary audio interfaces will provide a low latency recording option that means you can always stay on time with the project while adding more tracks.
Some audio interfaces come with lower latency levels to enable one to use the effect plugins in real-time as you record. On the other hand, others will feature their own DSP processing that is built into them.
It is crucial to understand that not all interfaces are compatible with all DAWs. This is because sometimes, a manufacturer will make an interface designed specifically for a specific environment. This is especially true for high-end interfaces.
However, most affordable interfaces are fine with pretty much any DAW. You only need the right drivers, depending on the operating system.
5. Form Factor/ Format
When it comes to the best audio interfaces, two form factors are available, including desktop and rackmount. The desktop versions will sit on the desktop where you can easily reach them, twist the knobs, and swap cables. In addition, they come with four or fewer inputs.
On the other hand, rackmount versions are approximately 19 inches wide and come with screws and ears to help mount them within the studio rack. However, some desktop versions will also have adaptable ears that allow them to be mounted, while some rackmount options will have removable ears and pegs that can be screwed on the bottom to avoid damaging your desk.
6. Sample Rates and Bit Depth
Ensure that the interface you choose can record at a minimum of 24 bits and 48 kHz (Hz, known as hertz, is the number of times per second the sample is taken). However, there are options that come with 16 bits and 24 kHz, which are recommended for hobbyists.
Even though the MP3s and CD audios are played back at 16 bits, a high audio bit length is always better. So if you want to ensure you get the most quality possible, then get converters that can handle 96 kHz or sometimes higher, although the 48 kHz will get the job done.
There are some additional features that should also be factored in;
- Size- The size will determine how portable the device will be. So, is the interface small, light, heavy, or big?
- Appearance- Is the chassis or the outer casing and the design looking attractive based on your preference?
- MIDI interfacing- Check the description to find out if the interface includes a MIDI for hardware control.
- DSP- Some interfaces can be used to save the CPU on the computer.
What Makes the Best Audio Interface Cost Vary?
The price of every interface is determined by two main things;
- The cost of manufacturing and marketing the interface
- Its audio quality is produced by ist components.
The cost of manufacturing includes the costs of the electrical components in them, the material of the chassis, for example, plastic, steel, etc., the cost of research and development, and the number of outputs and inputs.
In terms of quality, the more you get closer to perfection, the more the product will cost because of the large amount of experimentation and research that goes into it. The consumer or buyer of the interface will also be required to pay for the costs of marketing.
There are two main components that will determine the quality of your recordings- the preamplifier and the quality of D/A and A/D converters. This is where all the work goes to provide you clarity and true reproduction of the source signal.
For the best audio interfaces, you will be paying for the best mic preamps, the converters, and firmware that enable the components to talk to the computer. Additionally, the fancy chassis and circuit board also matter. When it comes to the best audio interface, it is all about the electronics used, and luckily, you get what you pay for.
How Many Mic Preamps and Instrument inputs Do You Need?
If you're a video producer, vocalist, or podcaster, one is enough, but two might be better if you plan on having guests. However, you need to ensure you have two XLR inputs if you want to use the two mics because each of them will correspond to an individual preamplifier. Although most combo inputs will have two Hi-Z inputs for instruments, it is always a great idea to make sure.
On the other hand, if you're planning on recording on a full band, you can as well get away with two, but you need to go through the layering of tracks. This all depends on whether you want to record a live performance for everyone at once or record the drums first, then let everyone take turns from there.
The number of inputs you need for recording can grow quite fast with the popular options of four and eight inputs. Most times, you buy two of the same interfaces and daisy chain them to have up to 16 inputs. However, there are some individual interfaces that provide up to 36 inputs.
Understanding the Digital Signal Processing Software
Digital Signal Processing (DSP) is software found in audio interfaces with 8 outputs or more. You install it on your computer, and it allows you to create mixes with the interface output.
Additionally, this software allows you to make headphone mixes that won't affect the original sounds of the recording. Although this can be done from the LED panel in front of the LED panel and on the front of the interface, it's not efficient.
The Digital signal processing software is a lifesaver because it is much better than any analog audio technology. This software will even provide a headphone amplifier and cue systems to allow you to talk to people through the headphones and microphones that are plugged in.
This feature may be installed on the lower-end interfaces, but one might not be able to use it depending on the company. For example, PreSonus have Virtual Studiolive, RME has Totalmix, MOTU has CueMix, etc.
It is most often included on CD in the packaging when you buy the audio interface, or sometimes you are directed to download from their official site. They are all full-on onboard digital mixing console software with mock input jacks, subgroup assignment, faders, panning control, even auxiliary sends, and more.
The software is similar to what you would find in digital audio workstations, but it is meant for monitoring instead of mastering and mixing. For example, the analog decibels (dBu) have a similar digital signal known as decibels Full Scale (dBFS), which you can monitor in the software. The key of the software is to avoid distortion and clipping while still having the best signal-to-noise ratio.
So, Which Software Comes with the Audio Interface Purchase?
The software that comes with interface purchase varies from one model to another and one brand to another. Some of the best audio interfaces will come with limited versions of Digital Audio Workstation (DAWs), for example, FL studio or Cubebase.
Unless you're planning to buy a full mixing console, you're probably not going to get a fully expanded version of Logic Pro or Pro Tools. Therefore, it is important to ensure that the best audio interface can be used with the DAW on your computer.
Although DAWs compatibility is a rare issue, it is always worth checking, especially if you're using an interface with four or more inputs. Check for the operating requirements as well. You may sometimes get plugins for popular DAWs like amplifier emulators and compressors with better audio compression algorithms than stock plugins, advanced audio filter options, parametric equalization, etc.
Frequently Asked Questions (FAQs) on Audio Interfaces
1. Does the audio interface improve sound quality?
Yes, an audio interface helps improve the sound quality significantly. This is done by accurately reproducing the sound that is passed into it and out of the studio headphones or monitors.
2. Does the quality of the audio interface matter?
Yes, they do matter. For example, 144dB of range and 24-bit audio provides production professionals the range they need for processing audio smoothly. A cheap interface may affect the sound quality, making it difficult to improve the audio quality. A poor quality interface may negatively impact the quality of the audio produced by your computer.
3. How do I know if my audio interface is bad?
Most often, a bad interface can lead to a low dynamic range and noise distortion. To find out if the interface is bad or not, check if the interface has a great dynamic range, a non-existent noise level, and a low distortion.
4. Will an audio interface reduce noise?
No, when it comes to noise reduction, it needs to be as close to the source as possible. This implies that the best way to reduce noise is to reduce the ambient noise. You can do this by use of sound isolation materials in the dedicated recording room.
5. What is the difference between sound card and audio interface?
A built-in soundcard will most of the time have very few and simple inputs and outputs, which are connections that allow you to get sound out and in of your computer. On the other hand, an audio interface will have one or more input channels: XLR type connections (microphone cable) and 1/4 inch jack type connections (guitar cable).