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Reference
Reference

The Grid and the DSP budget

Thirty-two slots, four rows, two parallel paths. Understand the pairing and most of this device's mysteries stop being mysterious.

The Grid
Gridleak diagram, not a screenshot

How to get hereThe Grid is the Quad Cortex's home screen — it's what you see when a preset is loaded.

1AUnsavedBank / slot · preset name↶ ↷undo / redoAsceneSave☰main menuPresetmode selectorTap a + to add a block · 8 slots per rowsignal flows →Pair 1 — one reverbPair 2 — one reverbIn1Out1/2Row 1Path A · mainGATESCREAMERBRIT 2203ampCABRow 2Path B · from row 1SsplitterDELAYREVERBMmixerRow 3Path A · mainRow 4Path B · from row 3SsplitterMmixer

  1. Row 1 is your main path

    Signal enters at the left and runs right. Amp and cab go here. If you never touch a splitter, this row is your whole rig and the Quad Cortex behaves like an ordinary pedalboard.

  2. The splitter sends a copy down

    It takes what has reached this point on row 1 and drops a duplicate onto row 2. Both then run in parallel. The S icon lives at the far left of row 2 and cannot be deleted — only dragged.

  3. Row 2 is the parallel path

    Reverb and delay here sit alongside your dry signal instead of on top of it, so ambience gets big without smearing note definition. This is the single most common reason to touch the Grid at all.

  4. The mixer merges it back

    Row 2 rejoins row 1 here. Set the wet row well below the dry one — a parallel path 3 dB hot sounds fine in a bedroom and like mud through a PA.

  5. Rows 3 and 4 are a second, unused pair

    A whole other main-plus-split pair, empty in this preset. When the unit refuses a second reverb while the CPU meter reads a third, this is where it goes — the limit is one per pair, not one per preset.

Quad Cortex User Manual 4.0.0 · Quad Cortex Wiki: FAQ
Shape

Four rows that behave as two paths

Four rows of eight slots

Thirty-two device block slots in total. Neural's own wording is “four rows, each containing eight device block slots”.

Quad Cortex User Manual 4.0.0
Rows 1 and 3 are main rows; rows 2 and 4 are their split rows

Neural call rows 1 and 3 “Path A” and rows 2 and 4 “Path B”, which reads as though 1 and 3 are joined to each other. They are not. Path A means main row and Path B means parallel row: row 2 splits from row 1 and merges back into it, row 4 does the same for row 3.

Quad Cortex User Manual 4.0.0 · Quad Cortex Wiki: FAQ
So the pairs are 1 with 2, and 3 with 4

That pairing is the unit everything else is enforced against — it is why the reverb limit is “one on the 1/2 pair and one on the 3/4 pair” rather than one per preset.

Quad Cortex User Manual 4.0.0 · Forum: the limit of gears
Two side-chain devices per row pair

Up to two side-chain devices per pair of rows within the same preset.

Quad Cortex User Manual 4.0.0
Dragging a block between paired rows creates the split for you

Move any block vertically between rows 1 and 2, or between 3 and 4, and a splitter/mixer path is created automatically. You do not place them by hand — which is why they seem to appear from nowhere.

Quad Cortex User Manual 4.0.0
Input and output blocks turn red when they clip

That is the clipping alert, and it is per-block: a red input block means lower IN 1 LEVEL in I/O Settings, while a red output block on a row means something on that row is too hot and the device parameters are where to look.

Quad Cortex User Manual 4.0.0
Splitters and mixers cannot be fully deleted

Rows 2 and 4 carry a splitter and a mixer that will not go away. To clear a split, drag the S icon fully left and the M icon fully right, then exit to Grid view and delete the empty split rows.

Quad Cortex Wiki: FAQ
DSP

The CPU meter is not the thing stopping you

The most common Quad Cortex frustration goes like this: you try to add a second reverb, the unit refuses, and the CPU meter is showing a third. So you start deleting things, which does not help, and you conclude the meter is broken.

It is not broken. It is simply not the constraint you have hit. Read these four rules in order — the second and third are the ones nobody tells you.

01

Bypassing a block does not free any DSP

Neural state it plainly: bypassing or disabling blocks does not reduce CPU consumption. A bypassed delay costs exactly what an active one costs.

Do thisTo reclaim processing, delete the block. Bypass is a performance control, not a budget control.

Quad Cortex User Manual 4.0.0
02

The CPU meter is not the binding constraint

Owners routinely hit “cannot add device” at around a third of the meter. The meter is real, but it is rarely what stops you first — the per-path limits below usually bite long before the total does.

Do thisWhen you are refused a block at low CPU, stop trying to make the preset smaller. Look at which path the blocks are on.

Forum: the limit of gears
03

Reverbs are limited per path, not per preset

The reported limit is one reverb on the row 1/2 pair and one on the row 3/4 pair, with spring reverbs excepted from the count.

Do thisMove the second reverb onto the other path rather than deleting it. This is why two-reverb presets are possible at all.

Community-sourced from Neural's own forum, not stated in the manual. We have flagged it rather than presenting it as a published spec — but it matches the behaviour owners describe consistently, and it is the only explanation that fits refusals at low CPU.

Forum: the limit of gears
04

Global EQ and the Input Gate get dropped silently

When a preset exceeds available processing resources, the Global EQ and Input Gate blocks are automatically disabled. The unit does not make a fuss about it.

Do thisIf your global EQ has mysteriously stopped applying on one preset and works on others, that preset is over budget. Delete something.

Quad Cortex User Manual 4.0.0
How to read the labels
Measured
Read off the hardware by us, not taken from a document.
Official
From the manufacturer's manual, FAQ, guides or release notes.
Community
Reported by owners. Corroboration, not a primary spec.
Our reading
Our interpretation, not something Neural DSP states.
Unverified
We could not confirm this, or sources disagree.
Routing

Four things worth building

Parallel wet path

You want big ambience without the reverb eating your note definition — the standard reason to touch the Grid at all.

  1. 1Build your amp and cab on row 1.
  2. 2Add a splitter after the cab so signal continues on row 1 and also drops to row 2.
  3. 3Put the reverb and delay on row 2 only.
  4. 4Mix the two rows back together and set the wet row's level well below the dry row's.

CheckSolo each row before you commit. A parallel path that is 3 dB hot sounds like a fine idea in a bedroom and like mud through a PA.

Quad Cortex User Manual 4.0.0

Two reverbs in one preset

The unit has refused to let you add a second reverb and the CPU meter is nowhere near full.

  1. 1Check which rows your existing reverb sits on — rows 1 and 2 count as one pair, rows 3 and 4 as the other.
  2. 2Put the second reverb on the other pair.
  3. 3If you genuinely need both on the same pair, make one of them a spring reverb, which is excepted from the count.
Forum: the limit of gears

Into the front of a real amp

You are using the Quad Cortex as a pedalboard, not as the amp.

  1. 1Run a TS cable from OUT 3/L to your amp's input.
  2. 2Do not put a cab block in the preset — a real cabinet is doing that job.
  3. 3Do not leave an amp block in the preset either. Two amps in series causes phase problems.
  4. 4Turn on Global Bypass to kill every cab, IR and capture block across all presets at once rather than editing them one at a time.
Quad Cortex Wiki: Using the Quad Cortex with a Real Amp · Quad Cortex Wiki: FAQ

Into a real amp's FX return

You want the amp's power section but not its preamp — usually the better-sounding of the two real-amp options.

  1. 1Run a TS cable from OUT 3/L to the amp's FX loop return.
  2. 2Leave the cab block out, as above.
  3. 3Expect the power amp to add some colour. It will be far less than running through the preamp.

CheckRemember the TS penalty: a TS cable on OUT 3/L costs you 6 dB against a TRS one.

Quad Cortex Wiki: Using the Quad Cortex with a Real Amp · Quad Cortex Wiki: Gain Staging

Global Bypass

Global Bypass disables every cabinet simulation, IR loader and Neural Capture block across all presets simultaneously.

This is the correct control for playing through a real amp and cab. The wrong way — the way most people do it first — is opening every preset and switching cab blocks off by hand, which you then have to undo before the next session.

Quad Cortex Wiki: FAQ
Where to go next