by Craig Anderton
I was a little taken aback recently when talking to a software developer, who estimated that somewhere between 60\\\% to 80\\\% of his company’s user base was connecting with a basic 2 x 2 interface. Maybe that explains why there are so many of them! But that does make sense. One of the changes computers have brought is making it possible for soloists and singer/songwriters to record their music simply and inexpensively—and if only one person is generating sound, you don’t need a lot of I/O.
The 2i2 is part of Focusrite’s Scarlett series; it’s the least expensive Focusrite interface, as well as the most portable. Suitable for Mac 10.6.5 and above (including Lion) and Windows XP SP3 and 7 (32- or 64-bit), it connects via USB 2.0 and is bus-powered. It’s also compatible with USB 3.0, but for the fourteen of you out there who are still using Windows Vista, note that it’s not officially supported. However, it’s been my experience that most interfaces that work with Windows 7 will work with a fully updated version of Vista, because (according to people who know more about this than I do) many of Vista’s later updates simply consisted of replacing sections of it with the code that would become Windows 7.
Focusrite makes the point that the 2i2 is "Pro Tools Ready," so of course, I had to test it with Pro Tools. It worked fine with PT 10.2, although I couldn't use a sample buffer lower than 256 samples (I had no problem getting well under 100 samples with other programs).
We can dispense with the rear panel (Fig. 1) in very few words: USB connector, 1/4” balanced TRS in and out, Kensington lock slot. Done.
Fig. 1: The 2i2 rear panel.
So, let’s move to the more interesting front panel. Each of the two inputs has a Neutrik combo jack that accepts XLR mic-level signals; if you use a 1/4” plug, a small toggle switch chooses between instrument or line-level input (Fig. 2).
Fig. 2: The 2i2 front panel. Note the “halos” around the knobs (the left one shows signal present, the right one indicates clipping).
A single +48V button applies phantom power to both inputs simultaneously, which I measured as +45.5V—unlike some USB interfaces, which deliver considerably less despite saying “48V” on the front panel. Each input also has its own gain control with a +10 to +55dB range. Conversion goes up to 24-bit/96kHz, with a choice of 44.1/48/88.2/96kHz sample rates (Fig. 3).
Fig. 3: The 2i2’s ASIO Windows control panel. The 2i2 also works with WDM on Windows, as well as Core Audio on the Mac.
The remaining controls are a large knob for the monitor output level, separate headphone jack with level control, and a direct monitor switch that runs the input directly to the output so you can monitor without latency. Of course with direct monitoring you won’t hear the effect of any plug-ins used in the computer, as direct monitoring bypasses the computer itself.
There’s no fancy mixing applet (as you’ll find with other Focusrite interfaces) because with two ins and outs, there’s really nothing to mix. However, this does mean that if you’re using the unit’s direct monitoring and, for example, plugging guitar into the left input and a vocal mic into the right input, you’ll be hearing them split in stereo. You can’t monitor them in mono unless you monitor through your DAW, as there’s no way to alter the stereo placement.
A very cool eye candy feature (hey, I’m easily amused) is an illuminated “halo” around the input knobs. It glows green with signal present, and red when the levels are just about to clip. Given that we’ve had red clip LEDs since interfaces were steam-powered, the variation is welcome.
The case is anodized metal, with a unibody design that wraps around the entire unit. The rear panel jacks use lockwashers (always appreciated!), and the input jacks and knobs have a solid feel. The switches wiggle around a bit, and don’t feel solid; while this probably doesn’t affect reliability, it’s a bit disconcerting at first. But overall, this is no cheap plastic piece of gear, and is actually quite substantial.
First of all, the specs I measured are generally better than what Focusrite quotes officially. For example, with the line input the quoted frequency response is ±0.1dB from 20Hz to 20kHz; that’s true, but what they don’t tell you is that with moderate gain, the response is down by only -0.3dB at 5Hz, so the extended low frequency response is excellent. Similarly, they quote noise at below -100dB but an average of -113dB is more like it.
For the mic inputs, I wanted to get as real-world a spec as possible. If the gain is way up, you’ll by definition get more noise than if the levels are low. Therefore, I set the mic gain so that when singing into the input with a dynamic mic, the peak levels hit a little higher than -6dB. I then took measurements based on that setting.
The frequency response was again within ±0.1dB from 20Hz to 20kHz, but the extended low end didn’t go quite as low—down about -2dB at 5Hz, and down only about -0.8dB at 10Hz (Fig. 4).
Fig. 4: Frequency response with the mic input at a typical gain setting for vocals. The line input has even slightly more extended low-frequency response.
For noise, the signal-to-noise ratio was comfortably below -110dB at typical gains (Fig. 5), and rising to below -90dB at maximum gain.
Fig. 5: The 2i2’s noise levels are extremely low.
THD and intermodulation specs were extraordinarily low, with a barely visible THD distortion product around 2kHz and not much else (Fig. 6). These increased somewhat at higher levels, but overall, distortion just isn’t there.
Fig. 6: The distortion products are essentially non-existent.
Distortion with the line-level inputs was equally low, although as expected, the noise floor is down somewhat—about 7dB (Fig. 7).
Fig. 7: Distortion graphs for the line-level inputs.
The only spec that fits with the 2i2’s low cost is the stereo crosstalk, which has a U-shaped curve. With line levels the minimum stereo crosstalk is a very respectable -85dB around 1kHz, but rises up to about -60dB at the lower and higher frequencies (Fig. 8).
Fig. 8: Stereo crosstalk for the line-level inputs.
With the mic inputs, the crosstalk didn’t dip down as low in the midrange, but the high and low extremes were pretty similar. These specs are respectable; you’d need a higher-end unit to get a significant improvement. Bottom line: Focusrite didn’t skimp on the preamps.
The package comes with a CD-ROM that includes Mac and Windows drivers, but of course, savvy users will immediately go to the Focusrite web site to check for the latest versions. Focusrite makes this easy by including a convenient “get the latest version” button on the CD-ROM. There’s also Ableton Live Lite, and the Scarlett plug-in suite (VST/AU/RTAS) with Compression, EQ, Gate, and synthesized (as opposed to convolution) Reverb.
Don’t dismiss these just because they’re free; they provide a useful alternative to equivalent plug-ins you may already have, and they’re quite efficient so you can sprinkle them liberally amongst your tracks.
The EQ (Fig. 9) has two parametric mids (100Hz - 3.2kHz and 2 – 12 kHz), and high and low bands.
Fig. 9: The Scarlett Suite EQ.
These have two responses, shelving and cut (e.g., low cut filter on the low band). In addition to each band having a frequency control (40 – 320Hz low, 6 – 18kHz high), another knob controls shelf boost/cut for the band, or the cut filter slope. There’s no brittleness in the high end, a smooth low end, and a “warm” character; there’s a distinctive character that’s a useful alternative to the average EQ bundled with DAWs.
The dynamics plug-in (Fig. 10) is designed to emulate the vintage 1960s “opto” sound. When pushed, it does have a recognizable vintage sound that’s good for “sucking” effects; it also handles being pushed more elegantly than some other compressors.
Fig. 10: The Compressor has the expected complement of controls.
However, you can also apply a much lighter touch, and add pretty much transparent dynamics processing. It has all the usual controls: threshold, ratio, attack, release, input/output gain, and metering.
The Gate’s main attraction is multiple modes (Fig. 11). Both channels can trigger themselves (like a standard noise gate), or one channel can trigger the other.
Fig. 11: The Gate plug-in is the most adventurous of the four.
Furthermore, with the latter, you can listen to the triggered signal just by itself, or with the “trigger” channel too. However, it doesn’t do this by sidechaining; you need to have separate left and right mono channels, then load the Gate into this stereo track. Aside from the mode options, Gate offers gain reduction amount, threshold, and attack/hold/release times.
The control set for the Reverb is limited, but relatively effective. There’s no choice of algorithms, but you can change size and there’s a dry/wet mix (Fig. 12).
Fig. 12: The Reverb controls are basic, although the Pre-Filter control is a welcome addition.
The Pre-Filter control is very useful, as it can emphasize (via lowpass or highpass filtering) which part of the frequency spectrum gets the most reverb. An “Air” parameter controls damping. While not very versatile, Reverb is a good match for certain sounds—particularly drums and voice. I had less luck with guitar, where the periodicity is more obvious.
The 2i2 is clearly intended to be all about price/performance. The preamp specs are excellent by any standard—not just “for the price”—particularly with respect to distortion.
One limitation is that there’s no MIDI I/O, so if MIDI is part of what you do, you need to look for an interface with MIDI built-in, or add separate MIDI I/O (with inexpensive USB-to-MIDI adapters like the E-Mu Xmidi 1X1 V3, adding MIDI isn’t a big deal).
It’s also worth noting that the 2i2 is eminently portable, not just because of its size, but because of being bus-powered. If you want to record rehearsals or a live performance, connect the 2i2 to a laptop, plug in a couple of mics, and go. The relatively light weight and compact footprint means it may even fit in a laptop bag compartment.
The 2i2 is a bit of a surprise. It’s not because expectations are low with Focusrite gear; quite the contrary. But with the 2i2, Focusrite has shown that they know how to keep the price low without sacrificing performance.
Craig Anderton is Editor Emeritus of Harmony Central. He has played on, mixed, or produced over 20 major label releases (as well as mastered over a hundred tracks for various musicians), and written over a thousand articles for magazines like Guitar Player, Keyboard, Sound on Sound (UK), and Sound + Recording (Germany). He has also lectured on technology and the arts in 38 states, 10 countries, and three languages.
Great review, especially the technical details. I was interested in the response curve and noise figures as I'm looking for an interface for acoustic measurement. It appears this interface would be just fine for such applications.
It wasn't what you reviewed, obviously, but the Scarlett 2i4 has some added features that would remove many of your stated downsides to the 2i2. The monitoring capabilities are improved, with a monitoring blend control and stereo-mono direct monitoring switch, so in your scenario of recording vocals on channel 1 and guitar on 2, you set the switch to "mono" and you get a summed signal in both ears. You also get the ability to adjust the overall mix of playback and direct input at the box itself, without fiddling with computer playback volume. The 2i4 has MIDI I/O as well, though as the unit is not its own synthesizer I do not believe you get direct monitoring of MIDI input (though with the all-digital signal of MIDI, latency should be drastically reduced).