Universal Audio OX Stomp — MIDI Editor & CC Reference

Control the Universal Audio OX Stomp from your browser — full MIDI CC reference for 10 parameters, interactive editor, and AI-generated presets. Free, no install.

Nitelite gives the OX Stomp a full browser-based control surface: turn every knob, flip every switch, describe the tone you want to the AI Tone Terminal, and save the results — all sent to the pedal live over MIDI (default channel 1). Works free in Chrome, Edge, Opera, or Brave — no install required.

Knobs

Control	MIDI CC	Description
ROOM	CC 35	Amount of mic'd studio ambience and air. Increase for more room ambience, decrease for a drier, close-mic'd tone.
SPEAKER DRIVE	CC 21	Dynamic response and breakup of the speaker cabinet. At low settings the cab sounds like a new speaker; raising it makes the cab softer and spongier with more breakup. At higher ranges, breakup is more obvious. At the top, the speaker approaches end-of-life — weaker, looser, darker, with possible sub-octave cone cry.
OUTPUT	CC 7	Pedal output level. OX Stomp's output is intentionally lower than other UAFX pedals to preserve the headroom of its complex modeling; typically unity lands between 3 o'clock and maximum.
MIC 1	CC 23	Level of Mic 1 in the overall pedal mix.
RIG	CC 2	Selects one of six Rigs assigned to the Rig knob positions in the UAFX Control app. Factory defaults: 1 = 4x12 Green Punch, 2 = 1x12 50s Twang, 3 = 2x12 Honkin Silvers, 4 = 4x10 Pristine Clean Room, 5 = 1x10 Roomy Tiny Combo, 6 = 2x12 Comfortable Lead. For full access to all 128 Rig slots, use MIDI Program Change. Note: the Rig knob is hardware-only and does not transmit on a real MIDI CC (this CC assignment is a display placeholder).
MIC 2	CC 29	Level of Mic 2 in the overall pedal mix.

Switches

Switch	MIDI CC	Positions
MIC 1 SELECT	CC 22	Dynamic 421 / Dynamic 57 / Condenser 414 / Ribbon 160 / Ribbon 121 / Condenser 67 / Direct Box
MIC 2 SELECT	CC 28	Dynamic 421 / Dynamic 57 / Condenser 414 / Ribbon 160 / Ribbon 121 / Condenser 67 / Direct Box
CABINET	CC 20	1x10 Black Cha / 1x12 Black GB30 / 1x12 Black D-UX / 1x12 JBG125 / 1x12 Blu 15 / 1x12 GB25 / 1x12 Blue J / 2x10 V-UX / 2x12 Ace Top / 2x12 Alnico 50 / 2x12 Black 8h / 2x12 D65 / 2x12 Two Verb / 2x12 JBF120 / 4x10 BMan / 4x12 GB30
ROOM MIC	CC 34	Condenser Stereo / Ribbon Stereo / Condenser Mono / Condenser 67 Mono / Ribbon 84 Mono / Ribbon 121 Mono

Footswitches

A — bypass on CC 12
B — bypass on CC 13

Special MIDI Functions

Delay Enable — CC 40. Toggles the master delay effect on/off independent of the Rig's stored state.
Reverb Enable — CC 60. Toggles the master plate reverb on/off independent of the Rig's stored state.
Mic 1 Mute — CC 25. Mutes Mic 1 without changing its level.
Mic 1 On Axis — CC 26. Sets Mic 1 on-axis (127) or off-axis (0). Off-axis softens the top end and tames presence.
Mic 1 Low Cut — CC 27. Engages a low-cut filter on Mic 1. Helpful with condensers on bassy cabs.
Mic 2 Mute — CC 31. Mutes Mic 2 without changing its level.
Mic 2 On Axis — CC 32. Sets Mic 2 on-axis (127) or off-axis (0).
Mic 2 Low Cut — CC 33. Engages a low-cut filter on Mic 2.
Room Mute — CC 37. Mutes the room mic(s) without changing the Room knob.
Room Damp — CC 38. Adds baffles and carpeting to the room to tighten and even out the room sound (Damped mode vs. Live).
Room Low Cut — CC 39. Engages a low-cut filter on the room mic(s).
Delay Time — CC 41. Master delay time (0.14 ms to 3 s depending on the delay type).
Delay Feedback — CC 42. Master delay feedback (-100% to +100%). Positive feedback is typical for delays; negative feedback gives more interesting chorus/flanger results.
Delay Mix — CC 44. Master delay dry/wet mix. Fully wet = only the delayed signal.
Reverb Decay — CC 61. Master plate reverb decay time (0.5 s to 5.5 s).
Reverb Mix — CC 63. Master plate reverb dry/wet mix. OX Stomp's reverb is 15% wet at the halfway point to allow finer control over lower mix settings.
Mic 1 Pan — CC 24. Stereo panning of Mic 1 (0 = hard left, 64 = center, 127 = hard right).
Mic 2 Pan — CC 30. Stereo panning of Mic 2 (0 = hard left, 64 = center, 127 = hard right).
Room Pan — CC 36. Stereo panning of the room mic(s).

Hardware Presets

The OX Stomp has 128 hardware preset slots. Nitelite can save your current settings to a slot and recall slots via MIDI program change.