Faders

A fader turns a run of pads into one control. Pressing a pad sets the level: the first pad is the minimum, the last pad the maximum. The pads blend between two colours up to the level and dim above it, so you can read the level on the Launchpad.

Use a fader for anything with a range: the volume of your microphone in OBS, the system volume, a light’s brightness through a web API.

Create a fader

1. Right-click the pad where the fader should start (its minimum) and choose New fader here….

2. Give it a Name, for example mic. The name is how other actions find it.

3. Pick a Direction (Up, Right, Down or Left) and how many Pads it uses. The label shows how many fit from this pad.

4. Set the range with Value at the first pad and Value at the last pad, and the Unit and Decimals of the level shown on the pad.

5. Switch to the Actions tab at the top of the editor and add the actions the level should drive under When the level changes. For a microphone: OBS: set audio on your mic source, with Volume from variable set to value.

6. Click Save.

The fader editor has two tabs: Fader for where the fader sits, how it looks and its range, and Actions for what it does. The Actions tab shows how many actions the fader has, for example Actions · 1.

Fader settings

The Fader tab:

Setting	What it does
Name	Identifies the fader for Set fader and in the fader list.
Variable name	What macros read the level as: fader. plus this name. Empty uses the fader’s name (spaces become underscores); a fader without a name is published under its id.
Direction, Pads	Where the fader runs from its first pad, and how long it is (at least 2 pads).
Preview	Shows the pads with the current colours and the level.
Colour at the minimum, Colour at the maximum	The pads blend from one to the other.
Brightness above the level	How bright the pads above the level stay, 0 to 60 %.
Value at the first pad, Value at the last pad	The range of the level, from the pad the fader starts on to its last pad. The two must differ.
Invert	Swaps the two values (and the display scale), so the fader counts the other way. See below.
Unit, Decimals	How the level is written on the pad, for example % with 0 decimals.
Show the level on another scale	Shows the level on a different scale than the real value, for example a −100 to 26 dB range shown as 0 to 100 %. The actions still get the real value.

The level is remembered, so a fader keeps its position across restarts.

Counting down

The first pad of a fader is the one you created it on; the run continues in its direction. Normally the first pad is the low end. Click Invert, or enter a Value at the first pad larger than the Value at the last pad, and the first pad becomes the high end: a fader from 100 to 0 has 100 at its first pad and 0 at its last. The editor then says Counting down under the range.

The actions and the fader. variable get the values as the fader shows them, so a counting-down fader sends 100 from its first pad.

What the actions receive

The Actions tab holds one list, When the level changes: the actions that run whenever the level changes. It works like a button’s action lists, with the same + Add action menu. (A fader on a touch strip has three lists instead.)

These actions can read the level as placeholders or in From variable fields:

Name	Value
value	The level in the fader’s own range, for example -12 for a −60 to 0 dB fader.
percent	The level from 0 to 100.
fraction	The level from 0 to 1.
step	Which pad is lit last, counted from 0.
steps	How many pads the fader has.
display	The level on the display scale, if you set one.

Match the unit to the action: a 0 to 100 fader fits a volume action set to %, a −60 to 0 fader fits one set to dB.

Every macro, not just the fader’s own, can read the level as fader. plus the name, for example {{fader.mic}}.

On a knob or a touch strip

A Launchkey has knobs, encoders and touch strips instead of pads for continuous control. Right-click one and choose Assign a fader… (a plain click on a free knob does the same): it holds exactly one fader, and the hardware supplies the value, so the editor drops Direction, Pads and the colours and keeps the range, the variable and the actions.

The level follows your hand at once — the LEDs, the on-screen control and the fader. variable are never behind a sweep. The actions wait until the movement comes to rest, so sweeping a knob across its range runs them once, with the value you stopped at, instead of hundreds of times on the way.

A touch strip has three lists instead of one, because it knows when a finger lands on it and when it leaves: When touched, While moving and When let go. The pitch strip springs back to the middle and its released actions get the value you let go at, not the middle. See a touch strip has three lists.

A knob or strip works even without a fader on it: it shows a position and you can drag it, it just has nothing to run.

Pads under a fader

The pads inside a fader belong to it. Buttons on those pads are hidden while the fader exists, and colour actions aimed at them are ignored. The fader editor warns you when a fader would cover buttons, and refuses to overlap another fader.

Remove the fader, and the buttons underneath come back.

Move, edit and remove

• Ctrl or ⌘ and drag any pad of the fader to move the whole fader. It only lands where every pad is free.
• Right-click a fader pad for Edit fader… and Remove fader, or Ctrl/⌘ and double-click it.

Set a fader from other buttons

The Set fader action moves a fader to a value, as if its pad had been pressed. It can also move it silently, without running the fader’s actions.

Writing to the fader’s variable works too, with the scope Everywhere. A button with Add to variable fader.mic, amount -5, scope Everywhere, turns the mic down by 5 on every press.

Tip

A pair of buttons with Add to variable fader.volume, amounts 5 and -5 and scope Everywhere, makes a volume up and down control, and the fader shows the result.