The Neural DSP Quad Cortex is a powerful, compact amp modeler that combines high-quality modeling, its own amp capture system and a touchscreen interface. It has quickly become one of the most talked-about units for both home recording and live use. This guide explains what the Quad Cortex does, how it captures amps, and how to record great tones with it.
What is the Neural DSP Quad Cortex?
The Quad Cortex is a floor-based amp and effects modeler from Neural DSP, the same company behind the popular Archetype amp sim plugins. It models amps, cabs and effects, lets you load impulse responses, and can capture real amps using its Neural Capture feature. It also functions as a USB audio interface, so you can record straight into your DAW. If the concept is new, our explainer on what an amp sim is covers the fundamentals that apply here.
Neural Capture: profiling on the Quad Cortex
One of the Quad Cortex’s headline features is Neural Capture, which creates a digital snapshot of a real amp or pedal — similar in concept to the profiling in our Kemper Profiler guide. You connect the amp, run the capture process, and the unit reproduces that specific tone. This sits alongside a library of built-in modeled amps, so you can use the unit fully without capturing anything yourself, then add captures of gear you love.
The touchscreen workflow
The Quad Cortex is built around a touchscreen. You drag and drop amp, cab, drive and effects blocks to build a signal chain, much like working on a tablet. Many players find this faster and more intuitive than menu-diving on knob-driven units, and it is a big part of why it competes so well against dedicated multi-effects pedals. It is one reason the Quad Cortex ranks highly in the best amp modelers.
Cabs, IRs and tone shaping
Like other top modelers, the Quad Cortex supports third-party impulse responses for the cabinet stage. Since the cab and mic carry much of the realism, loading quality IRs is one of the best upgrades you can make. Start with what impulse responses are and browse the best guitar cab IRs. A typical high-gain chain might run a noise gate, a Tube Screamer-style boost, an amp, a cab/IR, then EQ and time-based effects.
The Neural DSP ecosystem
The Quad Cortex connects to Neural DSP’s wider world of software. If you also use their plugins, you will recognise the tonal philosophy and some of the gear. We cover the software side in the best Neural DSP plugins, which is a natural companion if you want the same sounds in a plugin format for mixing.
How to capture an amp well
Neural Capture is only as good as the signal you feed it, so a careful setup pays off. Place your microphone on the speaker cab exactly as you would for a real recording — the same care you would take when learning how to mic a guitar cab — because the capture freezes that mic position and tone in place; if the mic is dull or harsh, the capture will be too. Let valve amps warm up for a few minutes so the tone has settled, and set the amp to the gain and EQ you actually want, rather than capturing a neutral starting point and hoping to fix it later.
Run the capture in a quiet room with stable mains power, and keep your monitoring level sensible so you can hear what the unit is doing. When the capture finishes, A/B it against the real amp at matched volume; small differences in brightness usually come down to mic placement rather than the capture itself. Save and clearly name each capture, including the amp, channel and rough gain setting, so your library stays usable as it grows.
How to choose between captures and modeled amps
There is no single right answer, and most users end up mixing both. The built-in modeled amps are convenient, fully adjustable, and cover a huge range of classic and modern voicings, so they are the fastest route to a usable tone. Captures shine when you have a specific amp whose exact character you want to preserve — a friend’s vintage combo, a studio amp you rented, or your own rig dialled in just right.
Remember that a capture is a snapshot of one setting. If you change your mind about the gain or EQ, a modeled amp lets you simply turn the knobs, whereas a capture would need to be redone. For most home recording, that flexibility makes the modeled amps the sensible default, with captures reserved for tones you cannot get any other way.
Recording with the Quad Cortex
The Quad Cortex doubles as an audio interface, making home recording simple:
- Connect it over USB and select it as your audio device in your DAW.
- Set levels with healthy headroom — see gain staging.
- Record the processed tone, and capture a dry DI on a separate channel where possible so you can re-tone later without replaying.
- For wide rhythm guitars, double-track and pan apart using how to double track guitars.
To slot it into a complete setup, see how to set up a home guitar recording rig.
Quad Cortex tips for better tone
- Audition tones in a mix, not just soloed, so they sit with bass and drums.
- Experiment with captures vs modeled amps — sometimes a built-in model nails a sound faster than capturing.
- Swap IRs to fine-tune brightness and body before reaching for EQ.
- Dial methodically using our guide to dialling in amp sim tones.
Common mistakes to avoid
- Stacking too much gain. Modeled high-gain amps already have plenty of saturation. Adding a heavy boost on top often turns clarity into mush; back the drive off and let the amp do the work.
- Judging tones at the wrong volume. A tone that sounds huge soloed at low volume can disappear in a busy mix. Always check it in context.
- Ignoring the dry DI. Recording only the wet, processed signal means you are locked into that tone forever. Track a DI alongside it so you can re-tone later.
- Neglecting the noise gate. High-gain chains pick up hum and hiss between notes. A correctly set gate cleans this up without choking your sustain.
- Hoarding presets. A handful of well-organised, well-named tones beats hundreds of half-finished ones you can never find.
Frequently asked questions
How is the Quad Cortex different from a Kemper?
Both can capture real amps. The Quad Cortex pairs capture with a large library of modeled amps and a touchscreen workflow, while the Kemper built its reputation primarily on profiling and its huge profile library. They are different routes to a similar goal.
Can the Quad Cortex be used as an audio interface?
Yes. It connects over USB and lets you record directly into your DAW, often capturing both the processed tone and a dry DI for re-amping later.
Do I need to capture amps to use the Quad Cortex?
No. It comes with modeled amps, cabs and effects you can use straight away. Neural Capture is an extra feature for snapshotting gear you own, not a requirement for getting good tones.
Can I use the Quad Cortex without a guitar amp or cab?
Yes. Many players run it directly into studio monitors, headphones or front of house, with the modeled cab or an impulse response handling the speaker stage. This is the most common way to record at home and means you do not need a physical amp at all.
Do third-party impulse responses make a real difference?
They can. The cab and mic stage shapes a large part of the final tone, so swapping in a quality IR often does more for realism than tweaking the amp itself. It is one of the easiest upgrades to a flat or boxy sound.
