Effects
openDJ has four kinds of effects:
- Deck effects: three on each deck, in the FX bar.
- Beat FX: one effect for the main mix or a deck, under the mixer.
- Color FX: one on each channel's filter knob.
- Pad FX: played from the pads while you hold them.
All of them follow the tempo of the track, so echoes and gates stay on the beat. Gates, flangers, phasers, the chorus and rolls also lock to the track's beat grid: a gate opens on the beat, and a roll starts on it.
The FX bar
The FX button in the top bar, beside WAVEFORMS, shows or hides the FX bar. It runs the width of the window, under the decks and above the browser: each deck's three effects across that deck's width, and the Beat FX in the middle, under the mixer.
Each effect has:
- Its name. Click it for the list of effects, or step through them with the arrows either side.
- ON to switch it on and off.
- Its length in beats, with ◀ and ▶ to halve and double it. Effects that have no length show a slider instead, for their main setting: reverb's decay, the filter's resonance, the bitcrusher's bit depth, the noise's sweep, the drive's tone, the ladder's resonance, the hall's decay.
- D/W, how much of the effect you hear over the dry track.
A deck's effects start as Reverb, Echo and Gate. They play one after another, so you can stack them.
In 4-Deck each deck's three effects are stacked in three short rows under that deck.
The effects
| Effect | What it does |
|---|---|
| Echo | Repeats the sound on the beat, fading out |
| Reverb | Puts the sound in a room or a hall |
| Filter | Low-pass and high-pass, with resonance |
| Flanger | A sweeping jet sound |
| Bitcrusher | Lo-fi: fewer bits and a lower sample rate |
| Phaser | A softer sweep than the flanger |
| Gate | Cuts the sound in and out on the beat |
| Roll | Repeats a short slice, for a stutter |
| Echo Out | Lets the track go, leaving its echo |
| Brake | Slows the track to a stop, like a turntable |
| Noise | A white noise sweep, for build-ups |
| Spiral | An echo that rises in pitch |
| Drive | Warm overdrive, from a little grit to full crunch |
| Chorus | Thickens the sound with slowly drifting copies, wide in stereo |
| Ladder | A resonant analogue-style low-pass that closes as you turn it up |
| Hall | A big, smooth concert hall, with pre-delay |
| Rev Roll | Repeats a short slice backwards |
| Filter Echo | An echo whose repeats get thinner (or darker) |
Switching an effect off fades it out quickly. On a DDJ-FLX4, SHIFT + BEAT FX ON/OFF releases the Beat FX instead: it stops taking in the track, and its echo or reverb rings out for a few beats.
Beat FX
The BEAT FX cell under the mixer is one effect on its own. Pick it by name, choose where it plays with 1, 2 or 1&2 (deck 1, deck 2 or both), then use ON, its beats and D/W as on a deck effect. On a DDJ-FLX4 the BEAT FX section of the controller plays it.
Color FX
Each channel's filter knob plays a Color FX. The small ▾ beside the knob picks which. Each deck keeps its own. The knob does nothing in the middle and more the further you turn it either way.
- Filter: a low-pass to the left, a high-pass to the right.
- Space and Dub Echo: the same filter, gentler, sent into a reverb or an echo on the beat. The tail rings on for a few seconds after the knob is back in the middle.
- Noise: adds filtered white noise.
- Crush: lowers the bit depth and sample rate.
On a DDJ-FLX4, SHIFT + SMART CFX steps through the Color FX.
Pad FX
The PAD FX 1 and PAD FX 2 pad pages play an effect while you hold the pad, and stop it when you let go: quick throws without touching the FX bar. See Pads for how to open them.
| PAD FX 1 | PAD FX 2 |
|---|---|
| Echo | Roll |
| Reverb | Gate |
| Low pass | Echo Out |
| High pass | Brake |
| Flanger | Noise |
| Phaser | Spiral |
| Crush | Gate Fast |
| Echo Max | Reverb Max |
When you load a track
Loading a track switches its deck's effects off, so the last track's echo doesn't carry over. Their beats and dry/wet stay as you set them. Turn this off in Settings › Decks under Auto reset on load (see Decks and mixer).
Plugins
openDJ runs CLAP and VST3 plugins, and Audio Units on a Mac. Nothing is loaded until you ask:
- Open Settings › Plugins, check the folders on the Folders tab and press Scan. Each file is opened once in a separate helper, a few at a time, so a broken plugin only fails its own row.
- On the Effects tab, tick the effects you want. Plugins are grouped by maker: tick a maker to take all of theirs, or open it with the arrow. The CLAP, VST3 and AU chips narrow the list to those formats (none lit shows all), and the search box finds a plugin or a maker. Only ticked effects show in the effect lists, under a line after the built-in effects, in every slot: decks, Beat FX, Mic and Aux. A plugin's first four settings follow the slot's parameter knobs.
The plugin's own window
When a slot plays a plugin, an EDIT button shows beside its ON (in the FX bar, the Beat FX and the Mic FX). Press it to open the plugin's own window, with its presets and every setting; press it again, or close the window, to put it away. The window floats above openDJ and is titled after the plugin and where it plays, for example "Pro-Q 3 · Deck 1 · FX 1". Closing it leaves the plugin playing.
When an FX unit plays on more than one deck, each deck has its own copy of the plugin and EDIT opens the first one's window. Changes made in the window last while the plugin stays loaded; openDJ doesn't keep them when it restarts the plugin or quits yet. On Linux the windows need X11 (XWayland on a Wayland desktop).
Each plugin runs in its own helper process. If it crashes, openDJ restarts it once with the slot switched off; if it crashes again, or keeps the audio waiting, it is switched off and a message says so. The music keeps playing either way.
Instruments
Tick an instrument on the Instruments tab of Settings › Plugins, then click Jam in the rail and drag it from the list onto a deck (see Jam on a deck). It plays through that deck's channel, with its EQ, filter, effects and fader.
The deck's header shows the plugin's format (CLAP, VST3 or AU) and its preset, with ‹ and › to step through the instrument's presets in the order the browser lists them. SAVE has Save, Save as new…, Rename… and Tags…, which sets what the preset is and how it sounds for the browser's chips. openDJ keeps the plugin's state, so the sound comes back next time. Right-click the cover to choose an image for the instrument, or drop one on the deck.
In 2-Deck the deck shows:
- A scope of what the instrument plays, and its level.
- TRIM and PAN. A safety limiter keeps the deck from clipping whatever the trim.
- Eight knobs for the plugin's settings. When it has more than eight, the page buttons 1 to 4 beside them show the next ones. Right-click a knob to pick the setting it turns; The plugin's own choice puts it back.
- OPEN, which opens the plugin's own window for every setting.
- KEYS ON PADS, which makes the decks' KEYBOARD pads, on screen and on your controller, play the instrument instead of the deck's hot cue (see Keyboard and key shift).
- A row under them with Scale, Chord, Arp, OCT − and +, and a keyboard that lights the notes held.
A 4-Deck strip shows the scope, OPEN, the first four knobs and TRIM, with the preset in its header.
Scale moves each note you play to the nearest note of a scale, so every key sounds in key with the mix. Off plays notes as they are. Auto takes the master deck's key. Or pick a root (C to B) and Major, Minor, Major pentatonic or Minor pentatonic. The keyboard on the deck marks the scale's keys and dims the rest.
Chord plays a chord built on the scale from each key: Triad, Seventh, or Power (root, fifth and octave). For a chord of your own, choose Learn a chord, hold its keys and let go; Mine then plays it from any key. Off plays one note per key.
Arp plays the notes you hold one at a time, on the mix's beat. Pick Up, Down, Up and down, Random or Order played to turn it on (Arpeggiator on turns it off and on), then RATE (1/4 to 1/32, with triplets), GATE (how long each note sounds, 25% to 100%) and OCTAVES (1 to 4). Hold keeps it playing after you let go, until you play new keys. It plays the chords from Chord too.
OCT − and + move the KEYBOARD pads up or down an octave, three at most each way. The pads play the white keys from middle C.
Any MIDI keyboard without a mapping plays the instrument. The keyboard button in the deck's header picks which one (Any keyboard or one by name) and which CHANNEL (Any channel or 1 to 16), and shows which keyboard played it last. See MIDI keyboards for which devices play instruments and which deck each one plays.