Universal Audio Volt 2 USB-C Interface Review: Portable Power

Founded in 1958 by audio engineer Bill Putnam, Sr., Universal Audio is known in the professional audio world for making top-shelf outboard gear (preamps, compressors, and the like) and best-in-class audio converters found. in the Apollo interface bar. In late 2021, the company announced its new Volt series, which aims to deliver UA’s sought-after analog audio and high-quality conversion in its most affordable and travel-friendly audio interfaces. I recently spent some time on the road recording and traveling with the Universal Audio Volt 2, a 2-in/2-out model focused on delivering the cleanest signal in a compact format. Here are my thoughts on the sound, design and workflow of the interface to assess how it stacks up against similar USB interfaces in its price range.

Drawing of the Universal Audio Volt 2

The Volt line runs the gamut in size and price, from the 1-in/2-out Volt 1 at $139 to the 4-in/4-out Volt 476P at $469. While each of the Volt interfaces is bus-powered via USB-C and includes a unique “vintage” tone option—more on that later—some of the models also include an integrated FET compressor in the style of the company’s 1176LN compressor. relatively powerful and bright compressor capable of producing response, transparent signal leveling, but costs several thousand dollars. The defining characteristic of the Universal Audio Volt 2, however, is its versatility and portability: its clean rectangular chassis measures approximately 7 x 5 x 2 inches, weighs just 1.4 pounds, and requires no wall warts thanks to its USB power supply -C bus. plan.

Design-wise, the Volt 2 improves significantly Universal Audio’s latest portable offering, the 6 x 6 x 3-inch, 2.4-pound Apollo Twin X, which requires wall power. The Volt 2’s control panel is also organized in a simple and easy-to-use manner, with most of the gain controls and monitoring options clearly labeled and placed next to the interface’s two XLR/¼-inch combo inputs, which accept microphone, instrument, and line level signals. A few backlit buttons offer access to 48-volt phantom power, instrument signal selection, and the Volt’s signature “vintage” mode, which activates solid-state electronics to add smooth clipping and warm saturation to input signals in the style of the Universal Audio Solo 610 Tube Preamp.

Like the Focusrite Scarlett 2i2, PreSonus AudioBox GO (which I reviewed in 2022), and other similarly sized 2-in/2-out USB interfaces, the Volt 2 features a switchable 48-volt phantom power that sends voltage to both inputs AT THE SAME TIME. This won’t be a problem for most users, but this limitation is something to keep in mind if you’re using vintage ribbon mics or other equipment that can be damaged by phantom power. On the conversion side, the Volt 2 features an impressive maximum audio conversion rate of 24-bit/192kHz, matching that of Universal Audio’s flagship Apollo series of interfaces, and allowing users to record extremely high-fidelity audio with a very small footprint.

A major design limitation of the Volt 2 is its lack of onboard DSP processing, which is required to run Universal Audio’s massive library of over 200 plug-ins. While none of the Volt series interfaces can run Universal Audio’s plug-ins, this points to a larger caveat in the company’s ecosystem. to run most UAD plugins, you need an Apollo series interface or an external UAD accelerator. This is somewhat rectified, but further complicated by the recent introduction of UAD Spark. This new subscription service offers access to around 20 of the company’s plug-ins without an Apollo interface or other external processors. In short: you’ll save a lot of money by choosing a Volt series interface over an Apollo, but you won’t be able to use it to run most of Universal Audio’s plug-ins.

Starting with the Universal Audio Volt 2

Setting up the UA Volt 2 for recording is easy thanks to its bus-powered design. To get started, I removed the interface from its packaging, unpacked the supplied USB-C cable, and plugged the Volt 2 into a USB port on my MacBook Pro. The Volt 2 turned on immediately and appeared as an available device for audio input and output in Logic Pro, the digital audio workstation of choice. If you’re using the Volt 2 in an older USB hub or want to save battery on your device, the included 5VDC to USB connector lets you power the interface with your own USB wall power supply.

I mostly tested the Volt 2 while traveling, which required setting it up and packing it in several different hotel rooms with different sized workspaces. Next to a 13-inch laptop, the Volt 2 is an ideal-sized interface for assembling a lean and mid-range mobile recorder, and because it doesn’t require a wall power supply, it’s easy to install almost anywhere. While on the road, I only had an electric guitar and a bass available for recording, and I plugged both directly into one of the Volt 2’s 1/4-inch instrument inputs while monitoring through the interface’s headphone output using a pair of KRKs KNS 8400 over-ear headphones. I also used the Volt 2’s direct monitoring feature, which offers lag-free monitoring of input signals via a front-panel switch to ensure a natural and comfortable performance experience.

Let’s say you’re setting up the Volt 2 as part of a larger studio setup. In this case, the interface has left and right TRS outputs on its back for connecting to studio monitors, and two MIDI ports for connecting older synths and other MIDI-compatible devices. Some smaller two-preamp interfaces, such as the Apollo Twin, include ADATs to allow users to expand their setups with additional inputs and outputs. While I would like to see this feature included in the Volt instead of the older and less used MIDI jacks, it would likely mean a significant increase in cost.

The sound of Universal Audio Volt 2

The UA Volt line promises clean, high-resolution audio conversion that follows in the footsteps of the company’s industrial Apollo series, and the Volt 2 fares very well in comparison. Compared to audio recorded with similar two-input interfaces, the Volt 2 sounds distinctly “open” in its high-frequency range with a relatively detailed midrange that does not suffer from the dark and “muddy” character that is often characteristic of the range its prices. In these respects, the transducers on the Volt 2 sound remarkably close to those on the Apollo, although I found the low-mids on the Apollo transducers to be slightly more subtle and focused. Although these differences are relatively small, this effect can sometimes be exacerbated when multitracking and can create extra mixing work on the back end.

The Volt 2’s unique “vintage” feature also adds another level of creative flexibility to the equation, and it was great to have that option while traveling with limited gear. With the feature on, the Volt’s inputs sound distinctly analog and old, replacing its clean and pristine default sound with a warm, round, saturated tone. Vintage mode also activates a soft clipper to flatten peaks in the input signal with analog tube-like behavior, giving a character that’s particularly great for early rock and Motown-style bass and guitar tones. While probably not a sound for everyone, the vintage mode is devastating for adding an extra layer of character and ‘glue’ to minimalist demo recordings and overdubs.

So, who should buy the Universal Audio Volt 2?

The Volt 2 has some of the cleanest and most musical converters I’ve tested in its price range. If you’re looking for a simple two-input travel interface, you’d be hard-pressed to do better. Its vintage preamp is also incredibly versatile. It adds a distinctly pleasant ‘pre-mixed’ analogue quality to input sources, saving time on mixing and bouncing, particularly when recording demos or overdubs. I wish the Volt 2 had included ADAT or S/PDIF to add additional inputs instead of MIDI—the tiny, forward-facing design of the Volt 2 seems to go against everything the old bulky MIDI tool stands for—and, unfortunately , the interface cannot perform UAD plugins. However, if you can get past these design limitations, the Universal Audio Volt 2 is an incredibly versatile and relatively affordable travel interface capable of delivering studio-quality recordings on the go.