Playing through a real amp
Which output, which jack on the amp, and the one switch that saves you editing every preset by hand.
Turn on Global Bypass. It disables every cab, IR and capture block across all presets at once — which is the job, and the alternative is editing them one at a time and undoing it later.
Use Global Bypass, not brute force
The wrong way — and the way most people do it first — is opening every preset and switching its cab block off by hand, then undoing all of that before the next session at home.
Global Bypass disables every cabinet simulation, IR loader and Neural Capture block across all presets simultaneously. One switch, reversible, no editing. This is what it exists for.
The reason to bypass cabs at all: a real cabinet is already doing that job. Leaving a modelled cab in front of a real one is the classic “why does this sound like a blanket” problem.
Quad Cortex Wiki: FAQ · Quad Cortex Wiki: Using the Quad Cortex with a Real AmpTwo ways in, and one is better
Both use a TS cable from OUT 3/L. The difference is what you plug it into.
- Into the amp's input — simple, and your amp's preamp colours everything the Quad Cortex sends it.
- Into the amp's FX loop return — this bypasses the preamp entirely. The power amp still adds some colour, but far less. This is usually the better-sounding option.
Remember the TS penalty: a TS cable on OUT 3/L gives you half the output voltage, so you need 6 dB back for unity. This is the most common cause of “it sounds weak through my amp”.
Quad Cortex Wiki: Gain StagingTake the amp block out too
Cab blocks are the obvious one, but the amp block matters just as much. Two amps in series — the modelled one and the real one — causes phase problems, and the result is a thin, hollow sound that no amount of EQ fixes.
If you are using a real amp, the real amp is the amp. Build the preset as pedals and effects only.