USB Audio Interface

Audio Interfaces

Published March 2025

Black Lion take a different approach with their latest audio interface.

What does ‘better’ mean in the world of audio interfaces? For most manufacturers, the answer seems to boil down to measurable numbers. With every new generation, we are promised more dynamic range, lower distortion, less noise, and so on. But is that actually what we want?

The thriving market for vintage‑style mic preamps would suggest that customers often have a slightly different understanding of ‘better’. Many of us are happy to enjoy a bit of non‑linearity and noise if it contributes to the sound we’re looking for, and there are a few interface manufacturers who acknowledge this preference, such as Universal Audio with their Unison modelling preamps and Heritage Audio with their i73 range. Even then, though, any departure from the usual numbers game applies only to the input stage. It’s assumed that although we might want to add colour on the way in, the rest of the circuitry should score as highly as possible when faced with an Audio Precision test kit.

Over in Chicago, Black Lion Audio are taking a slightly different approach. As well as offering vintage‑style preamps, they emphasise the primacy of subjective sound quality over quantifiable performance throughout their designs. Interestingly, though, the sonic benefits they claim for this are actually the same ones you’d usually associate with better specifications; the phrase “crystal clear” appears many times throughout their product literature. Of the product under review here, Black Lion maintain that careful design and component choice reduces “noise contamination” and “is optimised for best signal‑to‑noise ratio”, but they also say “We found that the best‑sounding parts in the output path weren’t necessarily the lowest noise components but they resulted in an optimal tone and signal purity that is instantly apparent to the listener.”

So what is the Revolution 14x16, and does its collection of “hard‑to‑get Vishay, Wima, and Nichicon capacitors and thin film resistors” actually make it sound better than rival products? The first of these questions is much the easier to answer, so let’s start there.

Revolution In The Head

The Revolution 14x16 is a USB audio interface that, as the name indicates, offers a total of 14 inputs and 16 outputs at base sample rates. Ten of each are accounted for by a single ADAT Lightpipe input and output and a stereo coaxial S/PDIF input and output. There is also word clock in and out on BNC connectors, which employ Black Lion’s proprietary Macro‑MMC clocking technology. Connection to the host computer is made through a single USB‑C socket. All of this digital I/O is located on the rear panel of the 1U chassis, which is sturdily made of metal and has integrated, non‑removable rack ears. Next to the USB‑C connector you’ll also find a socket for the ‘wall wart’ DC power supply. Given the emphasis on things like “highly filtered power rails” and “full‑circuit power decoupling”, the use of a generic external PSU is perhaps surprising, and although the rear‑panel socket has threads to accept a locking connector, the PSU doesn’t have one. Black Lion told me that this is a deliberate choice, as they often encounter stripped or damaged locking connectors on other interfaces sent to them for modding.

The Revolution 14x16’s front panel features two combi‑jack inputs for channels 1+2, along with three — count them — headphone ports.

Things get a lot more interesting, and unusual, when we turn to the Revolution’s complement of analogue I/O. On the output side, a conventional pair of rear‑panel monitor outputs on balanced quarter‑inch jacks is complemented by an additional pair of balanced line outputs, and no fewer than three front‑panel headphone sockets. The arithmetic behind the 14x16 designation would suggest that Black Lion are counting these as a single stereo pair, which is fair enough, since they all deliver the same signal. This maths is reflected in the number of inputs and outputs presented to the DAW, so on the output front, your software ‘sees’ a single stereo headphone output in addition to the monitor and line outputs and digital I/O.

It’s on the input side that the Revolution 14x16 gets really generous with the socketry. Whereas inputs 3+4 use the clean preamp design found in BLA’s existing Revolution interfaces, the first pair of inputs feature Black Lion’s Auteur preamp circuit, which is interestingly different from other ‘vintage‑style’ designs. For manufacturers like Heritage Audio, the mojo resides in the input stage, and the key component is the input transformer — which, under normal circumstances, is the very first thing the signal from your mic or instrument ‘sees’. By contrast, the Auteur design features a “modern front end that’s best described as fast and transparent”. Any vintage quality is conferred instead by the output stage, which features a Cinemag CM‑18313 transformer.

This sort of design choice is the subject of endless debate, but Black Lion’s approach makes sense to me. The sonic contribution of an input transformer is essentially fixed, and determined purely by the characteristics of the source signal. Locating the transformer on the output stage instead means that the user has some control over how hard it’s driven, and thus how much it colours the sound. You can deliberately apply more gain than is strictly needed in order to push a transformer‑balanced output stage, then compensate for excess level using a fader or other output attenuator if one is available.

At the back we have a USB‑C port, ADAT I/O, word clock I/O, S/PDIF I/O, a host of audio I/O on quarter‑inch jacks and, finally, another four combi‑jack inputs.

The Revolution 14x16 doesn’t have built‑in output attenuators, but Black Lion have gone one step further by providing balanced insert points on all four analogue inputs. These could be employed to insert an attenuator between preamp and A‑D converter, allowing the preamps to be overdriven, but you could also patch in EQs, compressors and other outboard gear. What’s more, the inserts are switchable from the front panel, so you can leave outboard or synths permanently plugged in and use the front‑panel buttons to decide what should be recorded. On top of that, the two Auteur preamps have combi XLR/jack sockets on both front and back panels. The availability of dedicated insert‑returns‑cum‑line‑inputs on all four input channels means that the jack part of each combi socket is given over to high‑impedance signals, so you can record up to four electric guitars at the same time. You can also use the Revolution 14x16 as a standalone mic preamp by treating the insert sends as analogue outputs. Consequently, although there are only ever four analogue inputs available for recording and monitoring, the Revolution 14x16 is uniquely flexible in terms of what and how much gear can be connected at once.

Numbers Up

As I’ve already mentioned, Black Lion Audio downplay the significance of audio specifications, and in some cases this leads them to be rather terse or obscure on the matter of measured performance. Thankfully that’s not the case with the Revolution 14x16, for which reasonably complete specifications are available. These suggest that the maximum input level for the two Auteur preamps is a meagre +6.5dBu at minimum gain, but Black Lion confirmed that this measurement ignores the 10dB pad, so in practice there shouldn’t be any problem accommodating hot signals. The variable gain control spans 60dB (albeit with some bunching towards the top of the dial), producing a total gain range of 70dB for inputs 1+2. Inputs 3+4 are less versatile, spanning a 55dB gain range with a maximum input level of +8.1dBu. All four preamps have individually switched +48V phantom power, which can produce a brief but slightly alarming burst of noise if toggled whilst a mic is connected. The Auteur preamps also have front‑panel buttons to switch polarity and toggle between front and rear inputs.

In other respects, the Revolution 14x16’s specifications are roughly in line with those of rival interfaces from the preceding generation. Whether you see that as a criticism will depend on whether you buy into Black Lion Audio’s conviction that one interface can sound subjectively better than another despite measuring less well. Dynamic range, for example, is given as 107 and 111 dB on mic inputs 1+2 and 3+4 respectively, 111dB on the line input, and 109dB on the line outputs. These figures are bettered on paper by most current alternatives, even more affordable ones such as the Focusrite Scarlett 4th Gen line, but they’re still objectively good, and miles above what’s needed to represent any real‑world audio signal.

Black Lion’s blurb describes the headphone outputs as being “plenty‑loud”; they actually deliver a maximum signal level of 2.65 Volts RMS, which equates to 10.7dBu. This is about the same as the Scarlett 4th Gen models and short of the SSL 18’s +18dBu or the Focusrite Clarett+’s 16dBu. I’ll give them “adequately loud in most circumstances”. Also worth noting is that 0dBFS corresponds to a line‑up level of +16dBu on both the input and output side. In and of itself this isn’t an issue, and as Black Lion pointed out to me, it maintains consistency across their own range, but most pro studio hardware is designed to operate at somewhat hotter levels, so this is perhaps not ideal for integrating outboard via the insert points.

Listen Here

Small audio interfaces, such as Black Lion’s Revolution 2x2, typically handle direct monitoring using a basic internal mixer that is controlled from the front panel. This has the advantage that there’s no need to install, learn or use a software control panel in order to interact with the interface. However, once you have more than a handful of inputs and outputs, this approach usually becomes impractical; a more complex digital mixer is needed to set up cue mixes and so on, bringing with it the need for a software utility to control this mixer. I was therefore fully expecting to have to get to grips with a software control panel for the Revolution 14x16, and was surprised to find that on macOS, there is none (Windows users do get a fairly straightforward software mixer).

Instead, there’s a simple onboard mixer that allows the user to set up a single cue mix from sources that comprise the four analogue inputs, the main stereo playback signal from the DAW and the two additional DAW playback signals that feed line outputs 3+4. Each of these can be switched into or out of the cue mix by pressing a button, with its level set using a dial that runs from zero to 100.

This is super simple to use, but of course the price you pay for not having to install a software control panel is some fairly obvious functional restrictions. For one thing, the cue mix is hard‑wired to all three headphone outputs, where it is summed with anything sent direct from the DAW to the Headphones L/R output, and can’t be routed to the monitor or line outputs. So if you want to listen to input signals on speakers, you’ll have to do so via your DAW and the Revolution 14x16’s buffers. For another, odd and even numbered sources are hard‑panned left and right in the cue mix respectively, and the only alternative is a single button that sums the cue mix as a whole to mono (though this, thankfully, leaves the Headphones L/R feed in stereo). A third consequence is that there’s no way to audition the digital inputs other than through the DAW.

So although the Revolution 14x16’s built‑in mixer is easy enough to use, you’re likely to do more monitoring through your DAW than is the case with other large interfaces, which makes low‑latency performance more important than usual. The 14x16 uses the standard XMOS/Thesycon ASIO driver on Windows, and the built‑in Core Audio driver on macOS, meaning that its performance is pretty much identical to that of most other current USB interfaces, albeit without the additional latency that built‑in digital mixers can introduce. At the lowest buffer sizes, it should be possible to achieve a round‑trip latency of under 8ms at 44.1kHz, which is plenty low enough for most purposes. As ever, though, lower buffer sizes mean higher CPU load, so if you need to increase the buffer size in order to get a big mix to reliably run, you may find your options limited if you want to record a last‑minute overdub.

Talking of monitoring, built‑in ‘master section’ control consists of a large dial governing the level of the monitor outputs, plus a mono button. There’s no talkback or speaker switching, nor even a mute button. Monitor control features on interfaces are rarely as comprehensive as you’d find on a dedicated unit or a large‑format mixer, but even so, this feels a bit parsimonious. On the plus side, level control takes place in the analogue domain, which is in keeping with Black Lion’s audiophile ethos.

Striking Out

And so to the question I’ve been avoiding so far. How does the Revolution 14x16 sound? Well, as far as the input stage is concerned, channels 1+2 basically reproduce Black Lion’s Auteur MkIII two‑channel mic preamp, but with insert points and built‑in A‑D conversion. And that’s a good thing. The documentation suggests that at moderate gain levels, you should be able to achieve “the fast attack of American‑style preamps”, while pushing harder can deliver “the warmth and colour of classic British preamps”. However, unless you patch an attenuator into the insert points, you’ll likely clip the A‑D converter before warmth and colour becomes particularly prominent. The best I was able to achieve was a subtle but attractive low‑mid bloom on sources such as vocals. The preamps on inputs 3+4, meanwhile, are fairly typical of modern audio interface designs, and sound very clean to my ears.

Do Black Lion’s audiophile component choices give it a subjective edge over competing products?

What, then, of the rest of the unit? Do Black Lion’s audiophile component choices give it a subjective edge over competing products? Or do its slightly less impressive audio specs manifest in audible issues? For me, the answer is ‘no’ in both cases. Whilst it might concede a few dB of dynamic range to rival interfaces, the Revolution 14x16 still has far, far more on offer than you need to either record or mix music of any sort. In the real world, its technical performance is more than adequate for any application. And when it comes to subjective sound quality, reliable A/B comparisons with other audio interfaces are very hard to make. Some people may have golden ears that can detect the alleged sonic imprint of different D‑A converters, but I’m not one of them. In all honesty, I didn’t hear the Revolution as sounding better, worse or significantly different from other interfaces that have crossed my path recently. In my view, audio interfaces in this price bracket have long since left behind the point where sonic integrity was an issue, and the Revolution 14x16 is no exception.

For me, in fact, the main factors that differentiate the Revolution 14x16 from other interfaces are less to do with sonics and more to do with functionality. This is a product that really doesn’t have any direct rivals. Like the similarly priced Heritage i73 Pro Edge, it boasts two channels of transformer‑based preamps, but it’s very different in other respects, and even the preamps themselves aren’t that similar. And compared with other rackmounting interfaces, its feature set is completely different. Even if you set aside the Auteur preamps, there’s nothing else I know of that has three headphone sockets, or switchable insert points on all four inputs; but equally, the Revolution is more limited in terms of direct monitoring than other rackmount interfaces. If you’re considering the Revolution 14x16, I actually think the comparison that makes most sense is not with any other interface alone, but with the combination of an Auteur MkIII plus a third‑party interface. Either way, Black Lion Audio have done very well to find an unfilled niche in a crowded market.

Pros

Switchable inserts on all four analogue inputs, plus duplicate front and rear sockets for the first pair, make for very flexible connectivity.
Transformer‑balanced Auteur preamps on inputs 1+2 add a touch of character.
Three headphone outputs.
No software control panel to learn, at least on macOS.

Cons

Direct monitoring is limited, and there are minimal ‘master section’ features.
Wall‑wart PSU with non‑locking connector.
Line‑up level of +16dBu is on the low side for interfacing with pro audio gear.

Summary

Black Lion’s rackmounting audio interface combines vintage‑style mic preamps with a unique feature list that sets it well apart from any competition, both in terms of what it will do and what it won’t.