Review: Neural DSP Nano Cortex Guitar Amp Modeler

The Neural DSP Quad Cortex is undeniably one of the finest guitar amp modelers in the world. For a certain kind of gigging musician who wants to minimize bulk and doesn’t require much in the way of effects, it can pretty convincingly re-create any number of amps, and has plenty of options for bread and butter effects like delay, reverb, and chorus. Plus, its Neural Capture feature allows you to quickly and easily make bespoke presets based on your own gear, or even download captures from other users.

If you’ve got a vintage Big Muff and a Marshall half stack that you love but don’t want to drag around for simple club tours, you can create a model of your specific Marshall and Big Muff with just a few button presses on the Quad Cortex. There’s just one problem: It’s $1,699.

The Nano Cortex is Neural DSP’s effort to bring its unique capture abilities and powerful amp modeling to the masses. At $549 it’s still not cheap. You don't get a screen, or some of the more advanced functionality from the higher-end model, but my experience tells me it could be an incredible stage and studio companion.

No Screens

The most obvious sacrifice made in the name of size and cost-cutting is that lack of a touchscreen. The Quad Cortex is an absurdly complex device that would be impenetrable without the touchscreen. The Nano Cortex strips down the feature set down enough that navigating the pedal with just a few knobs, buttons, and footswitches is reasonable.

Where the Quad Cortex provides you with more than 90 amp models, 1,000 impulse responses, and 100 different effects, the Nano sticks with the greatest hits from that massive library. It ships with 25 amp models, 300 impulse responses (IRs), and single options for chorus, delay, and reverb, based on classic pedals.

That’s still quite a lot of potential combinations to contend with, and doesn’t account for the ability to load custom captures and impulse responses that you’ve either created yourself or downloaded from other Cortex users. Navigating them can be a little confusing since the only indicators on the pedal are five LEDs over each footswitch, and all your captures and IRs are divided into color-coded banks. But if you’re primarily sticking to a few core combinations it’s not too bad.

If you find yourself wanting to switch things up a lot, there is an excellent companion app. I’ve tested a number of pedals with mobile apps and they’ve always been pretty unreliable. They’re often buggy and the Bluetooth connections are finicky at best. I had no such issues with the Cortex mobile app. It connected quickly and reliably every time, and everything worked exactly as expected.

My one complaint is that searching for user captures is a bit of a crap shoot. Captures can be labeled with gain level, source (amp, cabinet, drive pedal, etc.), preferred instrument, and a detailed description. But, often they’re not, and there’s no way to preview a particular capture without going through the hassle of downloading it, sending it to your pedal, and assigning it a slot in one of the banks.

Fantastic Sounds

The Nano Cortex sounds every bit as good as the Quad Cortex. The straight-out-of-the-box amp sims and captures cover a decent variety of tones, and they’re all pretty usable. How close do the Mesa Boogie JP2C or Fender Princeton 65 come to the real deal? That I can’t tell you from personal experience. I don’t own these amps to do a side-by-side comparison. There are plenty of videos out there though on YouTube that do direct shootouts if you’re interested, and the results are usually pretty impressive.

I’ve been particularly impressed with the Ampeg and Aguilar bass amp emulations. For tracking and playing bass I rely almost entirely on plug-ins. They get the job done, but I’ve never been blown away by the results. The Nano Cortex, however, has been truly impressive. It delivers reliable tube-esque low-end thump without the four figure price tag or any latency.

Captures that you download from users via the Cortex app can vary greatly in quality, but it’s easy enough to find some really great ones. You can sort by popularity, and unsurprisingly you’ll find the Holy Grail of drive pedals, the Klon Centaur, at the top of that list. There are also well-established users on there like Tone Junkie and Rabea Massaad, whose uploads are always guaranteed to be of excellent quality.

While the Nano Cortex lacks the 100-plus effects of the Quad Cortex, the three it includes are really excellent. The delay is a generic though convincing emulation of a BBD (bucket-brigade device) analog delay. It’s nothing fancy, but it gets the job done. The reverb is a re-creation of the hall setting from the iconic Lexicon 224, an early digital reverb unit from 1978 that has been used on records by U2, Peter Gabriel, Pink Floyd, Kate Bush, the Talking Heads, and many more. Then there’s the chorus, a take on the Boss DC-2W Dimension. While personally I think the Lexicon 224 is a touch overrated, the DC-2 is a gorgeous effect, and Neural DSP does its lush and unique character surprising justice.

Capturing Your Amp

One of the biggest draws of the Nano Cortex is Neural DSP’s capture technology. There’s no denying it’s powerful, and it’s pretty simple to use. Plug in a couple of cables, press a few buttons, and you’re off. That being said, I find it much easier to do using the app than the onboard controls. Here you get much clearer feedback about your levels, and you can name and add descriptions to your capture, which is essential for managing your library.

In general the quality of the captures was also pretty damn impressive. It was able to create a nearly indistinguishable emulation of both the boost and drive channels on my Matthews Effects Architect at low- and mid-gain settings. It even did an admirable job at re-creating the near-fuzz of stacking both those channels at full tilt. Even my Fender Blues Junior miked up with a Shure SM57 fared pretty well, despite the acoustics in my attic studio being pretty trash. Obviously, though, if you’re trying to capture an amp using a mic, the acoustics of a room will make a big difference. And as I moved the mic further and further back the quality of the capture quickly deteriorated.

The Cortex also struggles with some more out-there fuzzes and distortions. For example, my favorite dirt pedal of all time is the Smallsound/Bigsound Fuck Overdrive. It’s inspired by the sound of William Basinski’s classic Disintegration Loops and attempts to capture the vibe of ancient tapes, blown-out amps, and fuzz pedals with dying batteries. In short, it sounds broken, and that’s the point. But the Cortex Neural Capture program ignores these sorts of dropouts, and what it gives me instead is a decent but pretty bog standard drive tone without the deeply flawed character that makes it so special.

A Place on Your Board?

Whether or not the Nano Cortex deserves a place on your board will depend a lot on what you’re looking for. If your preference is for set-it-and-forget-it pedals that do one thing with minimal fuss, you might be happier with something like Universal Audio’s UAFX lineup. I think they respond slightly more naturally to playing dynamics, but at $400 they’re still not cheap, and you’re only getting one amp sim for your money.

The Nano Cortex gives you an arsenal of classic amp and drive pedal emulations, and lets you easily model your own amp and pedals. It’s all the same high-quality sounds of the Quad Cortex, in a stripped-down package at about a third of the price.

It’s probably the most cost-effective and space-efficient way to stock your home studio with vintage amps sounds in hardware form. The benefits should be even greater for a gigging guitarist. Even if you just want to take your own rig with you on the go, this is a great and affordable option.