Adding a VST3 effect

Every source, Master and every bus can have its own chain of VST3 effects. Only VST3 effects: instruments are not supported, and only plug-ins built for Apple Silicon will load.

Master’s effects work on everything Master carries, the buses that return into it included, and come before Master’s fader, as in a recording app. So a limiter on Master catches a host who reaches Master only through a bus.

Adding one

Press the FX button on a source’s strip, or a bus’s, in the audio mixer. In the sheet that opens, press Add Effect… and choose a plug-in from what is installed on this Mac.

The FX button itself turns orange once a chain is not empty, so you can tell which sources and buses are being processed without opening anything.

Working with a chain

Each effect in the chain can be switched on and off on its own, without removing it, to compare with and without.
Editor opens a plug-in’s own interface, exactly as the plug-in itself draws it.
Changes apply live, while audio keeps running.

Presets

A plug-in’s editor window has a bar across the top, above the plug-in itself:

The preset menu shows the preset you last loaded or saved for this effect. Open it to see this plug-in’s presets and choose one to load it. Presets the plug-in’s maker installed for everyone are listed under Installed.
Save saves the current settings under the preset’s name, or asks for a name if there is none. It asks before replacing a preset that already exists.
⋯ has Save As…, Load from File… for a preset kept anywhere else, and Show in Finder.
Bypass switches the effect off and on, the same switch as in the FX sheet.

Presets are standard VST3 preset files (.vstpreset), kept where macOS keeps them for every app. Presets you saved in other audio apps on this Mac appear in the menu, and the ones you save here appear in those apps. A preset made for a different plug-in is refused.

Loading a preset sets the plug-in’s controls in place, and saving one reads them in place, with its window open and the sound running.

Saving a whole chain

The Chains menu in the FX sheet saves and loads a whole chain: every effect, in order, with its settings and whether it is bypassed.

Save Chain… keeps it on this Mac under a name, and it is then listed in the menu for any source or bus.
Save Chain to File… writes it anywhere, to take to another Mac, and Load from File… loads one from there.
Loading a chain replaces the effects that are there, after asking if there are any.

A plug-in the chain needs that this Mac does not have stays in the chain, shown as unavailable, and works again on a Mac that has it.

New and updated effects

Install or update an effect and start InterDirector: it finds it by itself as it starts, before any Show opens, so the Show you open can use it at once. Only what is new or changed is read, and a window shows the progress while it is; with nothing new, there is no wait. A notice names what it found. Rescan, in Settings ▸ Effects, reads every effect again.

Effects and the picture

Many effects delay the sound a little, to look ahead: a limiter, a linear-phase EQ, noise reduction. InterDirector lines every source and every mix up with the slowest, and holds every picture back by the same amount, so Program and every output stay in step with the sound however many effects you add, and without measuring again. Settings ▸ Audio, under the buffer, says how much the effects add. An effect switched off adds nothing. Adding, removing or switching an effect on or off on air makes each picture and sound jump a few frames once, as any delay change does. This trusts what each effect says it delays; one that delays more than it says is not covered.

Effects made for live shows

Any VST3 effect built for Apple Silicon works here. Our own InterPlugins are made for live sound, and add no delay at their usual settings, so no picture waits for them:

InterMic, on a presenter’s or singer’s microphone: rides its level, takes out the room or stage around the voice, and catches feedback as it starts.
InterMaster, on Master: pulls the mix together and limits its peaks before the stream and the recording. Its true-peak setting looks ahead 1.5 ms, which every picture waits for as above.
InterStream, in a DAW: sends a mix to InterDirector, or takes InterDirector’s sound back to the DAW. See Sound from a DAW.

If a plug-in misbehaves

Effects are read in a process of their own, so one that crashes or hangs while being read cannot take InterDirector with it. It is left out, a notice says so, and Settings ▸ Effects lists it with why and a Try Again button. It is read again by itself once it is updated. Everything else carries on.

The audio mixer, for the routing a chain sits on top of.