devices · Quad Cortex · learn · 03 of 10 · 9 min
gain staging, properly
the one thing
Start at 0 dB, then check that your loudest playing sits just below clipping. One is the default, the other is the check.
two pieces of advice, one procedure
There are two common answers. One says leave input gain at 0.0 and stop fiddling. The other says set it just below clipping.
Both are right, in order. 0 dB is the design target: the modeler is built to handle a hard-strummed humbucker there. “Just below clipping” checks that this holds for your guitar, and it is the adjustment to make when it does not.
One is a starting point and the other is a test. In sequence, they take two minutes.
the five stages, in order
Work these top to bottom. Each assumes the ones above it are already set.
- Input: I/O Settings, IN 1 LEVEL, start at 0 dB.
- Verify: same screen, play harder than usual, and the meter should just tickle the red. Adjust only if it does not.
- Preset output: the lane output at the end of the Grid row. Match levels between presets here.
- Device output: the output level in I/O Settings. Set it to 0 dB and leave it. It is a device-wide trim, not a per-preset one.
- The knob: VOLUME to maximum while you set all of the above, then trim it for the room.
With the volume knob halfway, no meter on the modeler shows what front of house receives. Max it, get the levels right, then trim.
Quad Cortex Wiki: Gain Stagingheadroom: 12 dB clean, 6 dB distorted
Clean tones have a far higher peak-to-average ratio than distorted ones. Distortion is compression: a saturated patch does not spike the way a clean one does.
So presets matched by ear at the same apparent loudness leave the clean ones clipping in the room while the high-gain ones are fine. Leave 12 decibels of headroom on cleans and 6 on distorted. Use the meter for this, not your ears.
three traps that are not your fault
Each of these is how the modeler works, not something you set wrong.
- The output meter and the lane output control are on different pages, so you cannot see both at once. Turn the lane output up until it flashes red, then back it off a known number of decibels. You find the ceiling instead of watching a needle.
- A TS cable on OUT 3/L or OUT 4/R halves the output voltage. Those jacks are balanced. You need 6 dB back to reach unity, and that costs 6 dB of headroom.
- The FX loop sends run at line level by default. Pedals expect something much quieter, so pull the send down, starting around −5 dB.
Do not reach for a limiter to tame a chain that is too hot. Digital clipping does not soften the way analog clipping does, and limiting trades a level problem for a tone problem. Find the stage that is too hot and fix it there.
Quad Cortex Wiki: Gain Stagingoutput level
1. the lane output lives on the Grid
It's at the end of the row, and it matches one preset's loudness to another's. This is the one to move.
2. the output meter lives in I/O Settings
Swipe down, then I/O Settings. Only this screen shows how hot the signal is, and it is a different screen from the control above.
3. you cannot see both at once
There is no combined view, so you cannot nudge the control and watch the meter. No setting adds one.
4. so measure by finding the ceiling
Turn the lane output up until the meter flashes red and note that number. Then back it off a known amount: 12 dB for clean presets, 6 dB for distorted. You measure against the ceiling instead of watching a needle.