Neural DSP · Amp

Neural DSP Quad Cortex Settings Guide

The leading floor-based neural amp modeler. Captures real amp and pedal DNA via machine learning. The Quad Cortex runs as a complete amp + effects system — settings refer to the amp block parameters that match traditional controls.

The best Neural DSP Quad Cortex settings start with: Input Level at 6/10, Gain at 5/10, Bass at 5/10, Mid at 6/10, Treble at 5/10, Presence at 5/10, Depth at 4/10, Master at 7/10. Adjust from there based on your amp, guitar, and room volume. For Blues: Input Level 6/10, Gain 4/10, Bass 5/10, Mid 7/10, Treble 5/10, Presence 4/10, Depth 5/10, Master 7/10.

What Each Control Does

Input Level
Low
Hot
Input gain before the signal chain. Set so the input meter peaks yellow, never red. Critical for accurate captures.
Gain
Clean
Saturated
Amp block drive. Behaves identically to a real amp's gain knob. Interacts with the modeled preamp circuit.
Bass
Thin
Heavy
Low-frequency EQ within the amp block. Affects the preamp character, not just the output.
Mid
Scooped
Forward
Midrange character. The most important EQ for mix presence on any amp model.
Treble
Dark
Bright
High-frequency response. Controls clarity and articulation. High settings add presence; low settings add warmth.
Presence
Smooth
Aggressive
Power amp treble resonance. Adds edge and definition above what Treble controls. Critical for metal tones.
Depth
Tight
Loose
Power amp bass response. Controls low-end bloom and tightness. Keep low for metal, push for blues/rock warmth.
Master
Silent
Full
Amp block output level. Setting this high and Input Level moderate drives the virtual power amp harder — adds compression and character.
Output Level
Quiet
Loud
Final output to interface or PA. Set to match your interface's nominal level (typically -18dBFS for 0VU).

Recommended Starting Settings

Safe starting positions for any style. Adjust from here based on your amp and room.

6
Input Level
5
Gain
5
Bass
6
Mid
5
Treble
5
Presence
4
Depth
7
Master

All values on a 0–10 scale. These are starting points — fine-tune by ear.

Settings by Genre

Blues
Input Level6
Gain4
Bass5
Mid7
Treble5
Presence4
Depth5
Master7

Use a clean Fender or Dumble-style amp model. Moderate gain, mid-pushed. Keep Depth at 5 for warmth. Recommended captures: Fender Deluxe Reverb, Two-Rock.

Rock
Input Level6
Gain6
Bass5
Mid6
Treble6
Presence6
Depth4
Master7

British crunch model (Marshall, Matchless). Moderate Gain — let the amp model do the work, not the input level. Presence around 6 adds Marshall clarity.

Metal
Input Level5
Gain8
Bass5
Mid5
Treble6
Presence7
Depth3
Master8

High-gain model (Rectifier, 5150, ENGL). Tight Depth (3) for palm-mute clarity. High Presence (7) for definition. Add a noise gate block before the amp at -40dB threshold.

Clean Studio
Input Level5
Gain2
Bass5
Mid6
Treble6
Presence5
Depth5
Master9

Low gain, high Master to drive the virtual power amp naturally. Use a clean Fender model. Add reverb and delay blocks after the cab IR.

Artist Settings

Documented settings used by professional guitarists on this unit.

Input Level6
Gain5
Bass5
Mid6
Treble6
Presence6
Depth4
Master7

Govan (Neural DSP endorsee) uses the QC live with a mix of clean and light-crunch captures of real amps. Mid-forward, responsive to dynamics. He typically runs Gain lower than most players expect.

Input Level6
Gain4
Bass5
Mid6
Treble5
Presence5
Depth5
Master7

Pierce (session guitarist) uses the QC primarily for studio direct recording. Clean to light crunch. High Master for virtual power amp saturation. He notes the captures behave like miked real amps — EQ accordingly.

Tips & Common Mistakes

  • Set Input Level so the LED meters peak yellow (not red) on hard playing. Too hot = distortion before the amp model; too low = noise floor issues.
  • Use "Captures" (neural recordings of real amps) for the most authentic response, or "Neural Amps" (built-in models) for versatility without captures.
  • The Quad Cortex runs better with a flat power amp + FRFR speaker than through a traditional guitar cab — the cab IR block is designed for a flat response system.
  • In the effects loop of a real amp, bypass the amp + cab blocks — run only effects. This is not a common QC use case but it works.
  • For metal, add a noise gate block (pre-amp) with threshold at -40dB and release at 50ms. Without it, high-gain captures hiss noticeably.
  • Gain on QC captures behaves exactly like the real amp — a capture of a JCM800 with Gain at 7 sounds like the real JCM800 at 7. Trust the model.

Neural DSP Quad Cortex — Common Questions

Best starting settings for Neural DSP Quad Cortex: Input Level at 6/10, Gain at 5/10, Bass at 5/10, Mid at 6/10, Treble at 5/10, Presence at 5/10, Depth at 4/10, Master at 7/10. Adjust from there based on your guitar, room, and playing style.

For Blues: Input Level 6/10, Gain 4/10, Bass 5/10, Mid 7/10, Treble 5/10, Presence 4/10, Depth 5/10, Master 7/10. Use a clean Fender or Dumble-style amp model. Moderate gain, mid-pushed. Keep Depth at 5 for warmth. Recommended captures: Fender Deluxe Reverb, Two-Rock.

For Rock: Input Level 6/10, Gain 6/10, Bass 5/10, Mid 6/10, Treble 6/10, Presence 6/10, Depth 4/10, Master 7/10. British crunch model (Marshall, Matchless). Moderate Gain — let the amp model do the work, not the input level. Presence around 6 adds Marshall clarity.

Input Level: Input gain before the signal chain. Set so the input meter peaks yellow, never red. Critical for accurate captures. (Low to Hot). Gain: Amp block drive. Behaves identically to a real amp's gain knob. Interacts with the modeled preamp circuit. (Clean to Saturated). Bass: Low-frequency EQ within the amp block. Affects the preamp character, not just the output. (Thin to Heavy). Mid: Midrange character. The most important EQ for mix presence on any amp model. (Scooped to Forward). Treble: High-frequency response. Controls clarity and articulation. High settings add presence; low settings add warmth. (Dark to Bright). Presence: Power amp treble resonance. Adds edge and definition above what Treble controls. Critical for metal tones. (Smooth to Aggressive). Depth: Power amp bass response. Controls low-end bloom and tightness. Keep low for metal, push for blues/rock warmth. (Tight to Loose). Master: Amp block output level. Setting this high and Input Level moderate drives the virtual power amp harder — adds compression and character. (Silent to Full). Output Level: Final output to interface or PA. Set to match your interface's nominal level (typically -18dBFS for 0VU). (Quiet to Loud)

Set Input Level so the LED meters peak yellow (not red) on hard playing. Too hot = distortion before the amp model; too low = noise floor issues. Use "Captures" (neural recordings of real amps) for the most authentic response, or "Neural Amps" (built-in models) for versatility without captures. The Quad Cortex runs better with a flat power amp + FRFR speaker than through a traditional guitar cab — the cab IR block is designed for a flat response system. In the effects loop of a real amp, bypass the amp + cab blocks — run only effects. This is not a common QC use case but it works. For metal, add a noise gate block (pre-amp) with threshold at -40dB and release at 50ms. Without it, high-gain captures hiss noticeably. Gain on QC captures behaves exactly like the real amp — a capture of a JCM800 with Gain at 7 sounds like the real JCM800 at 7. Trust the model.

Guthrie Govan settings: Input Level 6/10, Gain 5/10, Bass 5/10, Mid 6/10, Treble 6/10, Presence 6/10, Depth 4/10, Master 7/10. Govan (Neural DSP endorsee) uses the QC live with a mix of clean and light-crunch captures of real amps. Mid-forward, responsive to dynamics. He typically runs Gain lower than most players expect.