Levels
Two settings decide whether the Helix Stadium Floor sounds like the demo or sounds broken. Neither of them is a tone control, and both are buried in a menu.
Almost every "it sounds thin", "it sounds quiet", "it sounds harsh" or "it sounds fizzy" report comes down to two settings, and neither is a tone control. One is what you told the box your instrument is. The other is what you told it your speakers are. Get both right and the preset that sounded broken sounds like the demo.
Helix Stadium Owner's Manual 1.3.2First, tell it what you plugged the outputs into
Global Settings > Ins/Outs. The 1/4" and XLR outputs each get their own setting, so you can feed a stage rig from one and the desk from the other without compromising either.
- Stompboxes, or the front of a guitar or bass amp
- Instrument
- Studio monitors, or the line inputs on a mixer
- Line
- The XLR mic inputs on a mixer
- Mic
- A mixer, studio monitors, or an audio interface
- Line
Then tell it what your guitar is
Global Settings > Ins/Outs — Inst/Pad. The Stadium folds the pad into an instrument-versus-line choice and adds a third option that hands the decision back to the preset.
- A normal guitar or bass
- Off/Inst — instrument level
- Active or high-output pickups that clip the input
- On/Line — line level
- You want it decided per preset
- No Offset, then set Pad in the Input > Instrument block
The Matrix Mixer meters every channel, and its metering is pre-fader — it shows the level before that channel's fader. So a channel can read hot while sounding quiet, which is exactly the case where pulling the fader down hides the problem instead of fixing it.
The FX loops have the same choice
Each FX Loop is set to Instrument or Line on the same page — Instrument for external stompboxes, Line for rack processors, keyboards, drum machines or mixers. An FX Loop block can then trim its own Send and Return on top of that global choice.
The Volume knob follows the lit output button
The big knob controls one output pair at a time. Press the 1/4", XLR or Phones button to choose which, and the knob moves that one; link two or three and it moves them together. Worried about a boot or a cable bumping it mid-show? Press and hold the lit output button to disable knob control entirely — pressing any output button re-enables it. Line 6's own words: stop taping it down.
Three outputs, three separate mixes
Each output gets its own Matrix Mixer layer, so the 1/4" feed to your stage rig, the XLR feed to front of house and the Phones feed to your in-ears can carry completely different mixes of the same performance. Worth knowing before you try to solve a monitoring problem by editing a preset — the level you are unhappy with may only exist on one of the three.
There are three Global EQs, not one
One per output, even when the outputs are linked, so you can compensate for a boomy stage without sending that compensation to the desk. Copy EQ and Paste EQ move a curve between outputs when you do want them to match. One catch: Reset EQ leaves the Low Cut and High Cut bands active, so to get genuinely no Global EQ you have to bypass it rather than reset it.
Watch the block levels too
One more level worth knowing about: every block has its own Level parameter, and Line 6's advice is to leave it at 0.0 dB on most of them. Nudging three or four in a row is a common way to clip the output while every individual setting still looks reasonable.
Levels are half of it. The other half is the cab block — on into anything full-range, off into anything that ends in a real guitar speaker. Get both right and almost nothing else can make it sound broken.