A pro-grade interface with classic SSL tone
Review By David Blascoe
With nearly five decades of experience crafting some of the world’s most respected recording consoles, Solid State Logic (SSL) has, since 2020, also turned its attention to the project and home studio market with a line of affordable yet unmistakably “SSL-centric” audio interfaces. At the top of this range sits the well-connected, feature-rich SSL 18 USB-C audio interface.
Past Featured Reviews
Number Eighteen
Building upon the features and functions initially found in the SSL 2 and SSL 2+ (reviewed June 2020), and further refined in the company’s SSL 12 released in 2022, the first SSL interface to take advantage of the SSL 360 ecosystem, the new SSL 18 is the first full-scale 19″ rackmount member of the family.
We Got Connections
The SSL 18 is a 26-in/28-out, 32-bit/192 kHz, USB-C audio Interface. Analog inputs are by way of nine analog XLR/TRS 1/4” mic/line inputs (two on the front and seven on the rear), one of which is dedicated to talk-back.
Next are 10 balanced TRS line outs, two of which can be designated as insert sends along with a pair of adjacent 1/4” TRS balanced returns. These outputs are DC-coupled, allowing them to be used for sending CV signals to your favorite CV-equipped synthesizers and modules.
The analog I/O is completed on the front via a pair of TRS 1/4” headphone outs, each with its own level control.
On the digital side, the SSL 18 offers 16 channels of ADAT-based I/O (perfect for expansion with the SSL Alpha 8, which gets its own review next month), phono-based S/PDIF, BNC word clock out, as well as 1/8” TRS breakout cable-based MIDI I/O. There is also a 3-prong IEC mains socket and a UCB-C jack.
Controls and Monitoring
Across the front of the unit, each input has its own dedicated level knob and a push button. Pressing this button selects that channel, which then allows you to engage that channel＊s phantom power, polarity invert and a high-pass filter.
A fourth button engages the Legacy 4K mode, inspired by the legendary SSL 4000-series consoles. Flip it on, and the sound picks up extra harmonics and a subtle high-frequency boost. It＊s not heavy-handed, but it gives sounds that “console finished” quality.
You can monitor each input’s settings in a comprehensive LED-based display window, as well as view the unit’s input, output and clock settings.
Output monitoring is via a dedicated level control with cut (mute), alternate monitor selection, and talk back. Finally, there are the aforementioned headphone outs and a master power switch.
Conversion and Clarity
The SSL 18 offers 32-bit/192 kHz conversion with a 120dB dynamic range on the inputs (and headphone paths) and 125dB range on the monitor and line outputs. Thanks to this clarity and headroom, I noticed that the vocals felt clear and open, cymbals retained their shimmer, and synth bass remained round and defined, as just three examples. In other words, conversion-wise, the SSL 18 stays out of the way in the best possible sense.
Preamps
The SSL microphone preamps offer 67dB of gain, meaning even lower-output ribbon and dynamic mics are covered, and the noise floor is impressively low. As mentioned, two physical preamp – 1/4” combo inputs are available on the front of the unit. In addition to mic and line level, these can accommodate Hi-Z instrument sources as well.
On Drums
As a session drummer, one of my first tests was throwing a drum kit at the SSL 18, and it handled it like a champ. Overheads sounded clear and natural, with no harshness creeping in even on bright cymbals. The 4K mode on the room mics was a highlight—adding just enough grit and energy to make the drums feel bigger and gently more aggressive without losing definition. I tracked everything from soft ghost notes to full-on crashes, and the interface accurately captured the full range of dynamics.
The onboard SSL 360 mixer software (more on this later) made monitoring easy. I set up a dedicated cue mix with extra “room” in the headphones, and I noticed I instantly responded by playing harder and more bombastic. That kind of flexibility in real time really drives home how much SSL thought about workflow here.
On Vocals
In my opinion, vocals are where preamps are truly tested, and the SSL 18 didn‘t disappoint. With a condenser mic plugged into Input 1, I had more than enough gain to capture quiet passages without noise creeping in. Breaths and subtle vocal inflections came through with lifelike realism, while louder sections never felt pinched or compressed by the front end.
Engaging the 4K mode brought a nice lift to the vocal, which the vocalist really responded to—a little extra sheen in the highs and just enough harmonic saturation to make it sit forward in the mix.
On Synths
Running my Moog Sub Phatty through the SSL 18 showed off the clarity of the converters nicely. The synth‘s sub-bass had a solidity that didn‘t blur into the rest of the mix, and the filter sweeps retained their smooth, liquid quality even when pushed hard. It felt like the SSL 18 gave me exactly what the instrument was producing.
I also found the unit’s latency was low enough that playing felt immediate. I also appreciated that the SSL 18 offers MIDI I/O for syncing gear; it kept the Moog perfectly in step with the DAW clock.
On Acoustic Guitar
For acoustic guitar, I set up a simple stereo mic pair, and the SSL 18 captured every detail. Pick attacks felt crisp but not brittle, while the body of the guitar came through warm and full. With the high-pass filter engaged, low-end thumps and room rumble were cleaned up before they ever hit the DAW.
On another pass, I tried the 4K setting on one of the channels. The slight lift in the highs gave the guitar just a bit more sparkle. It‘s a small thing, but it can save time by giving you a head start toward a polished tone.
Monitoring
The monitoring section is both simple and effective. The alternative speaker switching allowed me to easily compare mixes between my mains and a smaller set of reference speakers. Output level options (+9dBu or +24dBu) let me match the interface to my monitors without distortion or guesswork.
The two independent headphone outputs deserve praise too. Each has plenty of clean power, and you can choose between different impedance modes depending on the headphones you‘re using—a feature rarely found in interfaces of this style. Whether I plugged in sensitive in-ear monitors or high-impedance studio cans, the SSL 18 drove them confidently and without hiss.
SSL 360 Software
While the hardware is impressive, the SSL 360 software is just as important. It‘s the control center for routing, monitoring and metering, and it‘s one of the most user-friendly mixers I‘ve seen bundled with an interface. I quickly built separate mixes for myself and for performers, each with different balances, without ever touching my DAW. The Mirror Routing option is a clever touch—you can send any input or aux directly to an output, which is perfect for creating custom monitor feeds or sending signals to external devices later on.
Profiles can be saved and recalled, so I created templates for tracking, mixing and writing sessions. That way, I don‘t lose time reconfiguring things when inspiration strikes. Add in the stereo loopback feature, and it‘s also simple to capture audio from a browser or another software app.
The Production Pack
Registering the SSL 18 unlocks the SSL Production Pack, a suite of plug-ins worth over $1,100. These include a selection of SSL channel strips, compressors and equalizers. Essentially, it provides a virtual SSL console experience that, through the SSL 360 software, integrates seamlessly with the SSL 12, SSL 18, and/or the company’s range of SSL U-Series controller surface options (which our Editor, Paul Vnuk Jr., is a big fan of and a daily user).
Conclusion
After several weeks, the SSL 18 proved itself to be a well-balanced workhorse, which I found quite inspiring to use.
The SSL 18 is well designed and feels built to last. It offers pristine conversion, versatile preamps, intuitive software and thoughtful features that make daily studio life easier. Whether you‘re tracking a singer-songwriter, producing electronic music or mixing full band sessions, the SSL 18 has the tools to keep up.
It doesn‘t just carry the SSL name—it lives up to it.
David Blascoe is a Nashville-based session drummer and engineer. He records and tours with a roster of artists, including his personal project, Black Fuse. @blackfusemusic @davidblascoe
Price: $1,199.99
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