What is it?
Neural DSP has fast become a household name on the new frontier of amp modelling and guitar effects but hitherto its rep had been built on the back of its range of plugins, many of which were designed in collaboration with high-profile artists such as Gojira, Cory Wong and Tosin Abasi.
Its first foray into hardware, the Quad Cortex, is a floor-based unit that presses all that next-gen algorithmic sorcery into service for what is quite possibly the most exciting amp modeller yet.
What makes it so exciting? After all, there is no shortage of powerful tech-forward modelling options on the market. Well, quite simply it's the power, the options, the functionality and the compact form that's created a buzz – and a design that places this embarrassment of riches within easy reach of the guitar player with a super-intuitive design.
Housed in an anodised aluminium unibody, the Quad Cortex features a bright seven-inch LED touch-screen that allows you to adjust parameters and arrange your signal chain.
The Quad Cortex derives 2GHz of DSP power from SHARC+ processors that gives it its name, and this puts a lot of sounds on the menu, and that's pretty awesome, but what will really blow your mind is how intuitive the Quad Cortex is. You won't need a degree in audio engineering to access all quarters of its formidable tool set.
You can adjust these sounds and access all the functions from the touch-screen. Alternatively, the stomp+rotary actuators sees the footswitches double as dials for a more hands-on experience. The screen is bright, clear and, crucially, it is big. There's no cycling back and forth through menus – you can lay it all out there on the screen, amps, cabs, effects all sharing space on one big desktop.
The Quad Cortex divides its operations into three modes: Preset, Stomp and Scene. Preset mode is, as you'd imagine, all about the presets, arranging each of the eight stomp buttons for selecting a preset, with presets stored in banks that can be accessed via the up and down stomp buttons.
There are 32 banks available to the user, which, with eight stomp buttons [marked A to H], makes for – yes, math fans – 256 presets. But wait, there are also 10 Setlist slots, making for 2560 presets in total. That is a lot of tones. Of course, you can create your own, and switch presets around easily with the Cortex app.
Stepping on the two footswitches to the right of footswitches A to H changes the mode (alternatively, use the touch-screen). In Scene mode, you can have eight different twists on the one preset, which means you could set up a scene for a song and then switch between sounds, say, for a mids-boosted sound during a chorus, a modulated tone a bridge section, or simply for applying a boost during a solo.
Being able to have eight iterations on the one core preset sound is for many an easier way of navigating the idea of presets. And once more, cycling through your scenes you can programme it to get you through a setlist.
Stomp mode takes a more granular approach to the idea of presets. You can assign effects, amps, IRs and your Neural Captures to a stomp switches and then use it like an analog pedalboard, using rotary encoders to adjust settings within each effect/amp. No matter how you use the Quad Cortex, the workflow is uncomplicated, and the experience lends itself to experimentation.
Neural Capture is another one of the Quad Cortex's features that'll make your jaw drop. Using Neural DSP's biomimetic AI technology, the unit can accurately capture the sonic characteristics of any physical amplifier, overdrive and cabinet.
The biomimetic part is worth emphasising, as this is what helps set Neural's tech apart, using a digital methodology to profiling gear that mimics the human ear. Neural says it is "the most natural-sounding capture solution on the planet."
Performance and verdict
The Neural Capture function is fast, easy and to our ears very accurate. There is an active community of users sharing their own captures online, making for another great source of fresh tones. Sadly, there's no desktop app just yet – it is in the works – but using the Cortex Android/iOs app, you can browse Neural Captures and add them as favourites.
When you check in with the unit, look them up under the "Starred and Shared With Me" menu and download them at will. Uploading your own is a drag and drop activity, and like most things with the Quad Cortex, it couldn't be easier.
Indeed, how Neural DSP has integrated all this bleeding-edge tech into a user-friendly package is quite an achievement. It allows you to experiment, of course, and in doing so you might lose the odd afternoon falling through the rabbit hole as you chase tones, but translating the sound in your head to a sound from the unit is as easy as it could be.
• Kemper Profiler Stage (opens in new tab)
Despite a couple of niggles, the Kemper Stage is an awesome all-in-one floorboard that we’d happily recommend as the core of any digital rig.
• Fractal FM3 (opens in new tab)
Compact and portable but packing enough functionality to for the gigging musician to use it as an all-in-one rig, the FM3 is another exceptional offering from Fractal. And it's a little more approachable in terms of price, too.
• Line 6 Helix (opens in new tab)
The Helix is a real powerhouse that can be used on its own or as the centre piece of an extended gear system.
The quality of the sounds is exceptional. That processing power is really brought to bear on the signal path. Even the most complex rigs are rendered with superb fidelity, and with the promise that more is to come (the unit will be updated over time, keeping it current) it suddenly begins to look like money well spent.
No, it's not cheap per se, but how much money have you wasted on physical gear that for one reason or another does not get much of an airing? Here, you have all your options on tap, and the Quad Cortex makes the case that you might never need anything else. This, indeed, could be your rig, and it's about the size of a laptop and weighs under 2kg.
The build quality is incredible, and is such that you could take this on the road with no trouble. The rotary footswitches are incredibly hardy and even more clever, affording the Quad Cortex an extra level of tweakability from such a small footprint.
There is also a veritably feast of connections here. A pair of XLR outs, MIDI in/out, two expression pedal inputs, USB, two effects loops for integrating with your pedalboards, a Capture output, stereo outputs and two combo inputs with high-grade microphone preamps, phantom power supply, and variable impedance controls so you can lay down vocals or put your synth through it. Neural DSP says it will be adding vocal effects to the unit in due course.
What doesn't it do? What doesn't it do? Well, it doesn't include the Neural DSP plugins. If you already have these, Neural DSP has promised they will make them available to QC users in the future. And it won't play the songs for you. But it will give you the sounds to play them. Indeed, play anything. And that's pretty cool. You might never need to buy another amp or stompbox again.
MusicRadar verdict: A pro-quality amp modeller and effects unit that presents its many features in an easy-to-use format, the Neural DSP Quad Cortex is a triumph of design. The sound quality is incredible, the user experience unsurpassed. This is the sort of kit to make a digital convert of the most devoutly analogue player.
- TYPE: Amp modeller and multi-effects
- KEY FEATURES: 50+ amp models, 70+ effects, 1000+ Impulse Responses, 7” display with multi-touch sensors, AI-powered Neural Capture, proprietary stainless steel stomp+rotary actuators, 2GHz Quad-Core, SHARC architecture, anodized aluminum, unibody, WIFI for wireless preset sharing, cloud backups and firmware updates, extra control via the Cortex app
- CONNECTIONS: Dual combo inputs, Dual effects-loops, 2x 1/4” output jacks, 2x XLR output jacks, headphone output,MIDI in, out/thru, Dual expression inputs, USB audio interface with Cirrus Logic codecs
- CONTACT: Neural DSP (opens in new tab)