Ever since the home computer took over audio recording duties from the venerable tape recorder, the conversion of audio from an analog electrical signal to a digital stream of ones and zeros has been a critical part of the process. While motherboards and consumer sound cards used to provide this capability – and in a pinch, they still can – the trend toward standalone or interfaces built-in to mixers continues to dominate.
Audio interfaces come in several ‘flavours,’ these being USB, Firewire, Thunderbolt or proprietary PCI or PCIe card. The most basic provide line-level analog inputs and outputs. Depending on the device, there may be digital ins and outs, such as AES, ADAT or S/PDIF. Still, others incorporate MIDI capability as well.
Most audio interfaces are 2-in/2-out. That is, these handle two audio tracks, both in and out, a stereo pair. That’s not, however, any sort of limitation. Even modest home recording systems can accept many more tracks simultaneously if the audio interface supports multitrack use. Additional tracks push up the cost of an interface.
Quality is another factor, usually determined by preamp sophistication and sampling rates. The electronics of an interface’s microphone preamp determine how well supplied is the analog/digital conversion process. Sampling should be a minimum of 16-bit, 44.1 kHz for CD quality audio, but many choose to sample at higher rates, such as 24/48 or 24/96. The highest quality available to a user is the highest rate offered by a particular interface.
Below, we look at three of the best audio interfaces currently on the market. This is by no means a comprehensive view, but it provides an overview of features, cost and value for a variety of home recording applications.
Top USB 2×2 Interface – Focusrite Scarlett 2i4
Of the top, the Focusrite Scarlett 2i4 is technically a 2-in, 4-out interface. This company’s Scarlett 2i2 is one of the most popular 2×2 interfaces, but the 2i4 adds several features for an additional 20 bucks that is money well-spent.
The Focusrite Scarlett series has a reputation for amazing sound quality at very affordable prices. This means both great sounding preamps and high-quality A/D converters. Sampling extends as high as 24-bit/192 kHz. The 2i4 is built like a tank and receives power through the USB bus. Only a single cable connects power and audio.
The $20 advantage adds a second pair of outputs. This permits such elegant signal routing as monitor mixes alongside master mix, so you can feed optimized tracks to musicians performing overdubs. There’s also MIDI in and out, 5-pin DIN jacks on the back, streamlining the connection to external MIDI devices for those who require them. If you’re not currently using external MIDI, this is an affordable way to bring in a fantastic interface with the ability to add MIDI later.
Supporting both PC and Mac platforms, the software included with the 2i4 is exceptional. Starter versions of both Pro Tools and Ableton Live headline the roster included with the 2i4 package. With a street price under $200, the 2i4 is an unbeatable mix of quality, value and features.
Top FireWire Audio Interface – Universal Audio Apollo FireWire
FireWire is a different breed of interface. Originating about the same time as USB 1.0, FireWire initially offered faster bandwidth, making it more suitable for audio, at least until USB 2.0 and 3.0 emerged. Currently, FireWire serves the high track count audio interface market, having a lower processor overhead than USB. You won’t find many 2×2 FireWire devices, if any at all, since USB ports are standard and FireWire requires a special purchase or add-on card for many PC computers. Mac computers more frequently feature FireWire ports built-in.
That’s why we rate the best FireWire interface as an 18×24 device, the Apollo from Universal Audio. The serious audio interface for a home studio that’s much different than the one requiring a 2×2 device. For a home recordist who plays in a band, for example, 18 inputs permit effective multitrack recording for later mixdown. There are even 2 high impedance inputs for connecting guitars and basses directly.
Note that of these 18 inputs, four feature XLR jacks, eight are ¼-inch phone jacks and the remainder are digital inputs, either ADAT or S/PDIF. The Apollo is intended as a mixed input device. There is even digital signal processing available onboard the Apollo, freeing the recording computer from these tasks and lowering overall system latency. As you might expect at this price point, audio quality is exemplary.
Top USB Multitrack Audio Interface – PreSonus AudioBox 1818VSL
With the increased speed of USB 2.0, multitrack USB became feasible. Given that USB 2.0 ports are virtually standard equipment on both PC and Mac platforms, audio interface developers threw their weight behind USB to reach the widest market. The PreSonus AudioBox 1818VSL aims toward a similar target as the Universal Audio device, but arrives at a price that’s more budget friendly, without giving up much in the quality department.
The 1818VSL also has a mix of analog and digital inputs. Eight inputs are analog – either XLR mic or ¼-inch line, with two of those line inputs high impedance and guitar-ready. Ten additional inputs arrive through ADAT or S/PDIF. Five-pin MIDI in and outs also augment the connections available through the PreSonus device.
What sets the 1818VSL apart is its remote wireless access. Supporting Apple’s iPad as a remote control, you can mix anywhere in your studio. You’re no longer tethered to your computer. This is the wave of the future, and it’s one that PreSonus rides well. The $400 price tag is much easier to take for most home studio budgets.
- 2-in/4-out analog unit with an additional 8 ADAT inputs available.
- Very high-quality preamps at a $300 street price.
Apogee Element 24
- Mac platform only, Thunderbolt interface. $600 price point.
- 10-in/12-out, 2 analog and 8 ADAT inputs. Also SMUX and S/PDIF optical compatible.
RME Fireface UCX
- USB 2.0, 3.0 and FireWire compatible, 18-in/18-out analog/digital mix.
- Onboard DSP, ultra transparent audio, latency-free, $1,600.