VIRTUAL DJ

MASTER

0:00

DECK A

No Track Loaded

0:00 / 0:00

BPM: ---

PITCH 0%

DECK B

No Track Loaded

0:00 / 0:00

BPM: ---

PITCH 0%

MID

LOW

FX A

FX B

A B

MID

LOW

SAMPLE PADS

▼

Record from: 0.0s

Set IN/OUT points on deck, then click

1 Z

Empty

2 X

Empty

3 C

Empty

4 V

Empty

5 B

Empty

6 N

Empty

7 M

Empty

8 ,

Empty

EFFECTS

▼

FILTER

TYPE

FREQ

RES

ECHO/DELAY

TIME

FEEDBACK

MIX

REVERB

SIZE

DECAY

MIX

FLANGER

RATE

DEPTH

MIX

BITCRUSH

BITS

RATE

MIX

VOCAL ISO

MODE

LOW

HIGH

MIX

Virtual DJ Help

Welcome to Virtual DJ

Virtual DJ is a browser-based DJ application with dual decks, a mixer, and effects rack.

Getting Started

Load a track - Click "LOAD TRACK" on either deck or drag & drop an audio file
Press Play - Click the ▶ button or use keyboard shortcuts (Q for Deck A, P for Deck B)
Mix between decks - Use the crossfader at the bottom center
Add effects - Toggle effects in the Effects section and adjust parameters

Features

Dual turntable decks with vinyl simulation
Pitch control with sync functionality
Key Lock - change tempo without affecting pitch
Loop controls with multiple beat divisions
3-band EQ per channel
Multiple effects: Filter, Echo/Delay, Reverb, Flanger, Bitcrusher
Visual waveforms and spectrum analyzer
Slip mode for seamless scratching
Mix recording with WAV and MP3 export
8 sample pads with keyboard triggers

Decks

Each deck has a turntable, transport controls, and a waveform display.

Transport Controls

▶ (Play/Pause) - Start or pause playback
CUE - Return to cue point; hold to preview
SYNC - Match tempo to the other deck
REV - Reverse playback direction
SLIP - Enable slip mode (timeline continues during scratching)
KEY - Key Lock: change tempo without changing pitch (preserves vocals)

Pitch Control

The pitch slider adjusts playback speed from -50% to +50%. The percentage display shows current pitch offset.

Key Lock (Master Tempo)

Key Lock allows you to change the tempo of a track without changing its pitch. This is essential for beatmatching tracks with different BPMs while keeping vocals sounding natural.

Without Key Lock: Speeding up a track raises the pitch (chipmunk effect), slowing down lowers it
With Key Lock: The original pitch is preserved regardless of tempo changes
The KEY button glows green when active
Uses real-time time-stretching (SoundTouch algorithm)

Loop Controls

IN - Set loop start point
OUT - Set loop end point and activate loop
EXIT - Exit the current loop
× / ÷ - Double or halve loop length
Beat dropdown - Set loop length in beats

Vinyl Scratching

Click and drag on the vinyl record to scratch. The tonearm follows playback position.

Waveform

Click anywhere on the waveform to seek to that position. The waveform shows the full track with the current position highlighted.

Mixer

The central mixer section controls volume levels and EQ.

Channel Controls

Volume Fader - Controls individual deck volume (vertical slider)
HI / MID / LOW - 3-band EQ knobs for each channel

Master Section

Crossfader - Blend between Deck A (left) and Deck B (right)
FX A / FX B - Effect send levels for each deck
Visualizer - Shows real-time spectrum analysis of master output

Effects

The effects rack provides five audio effects that can be toggled on/off.

Filter

TYPE - Low Pass, High Pass, or Band Pass
FREQ - Cutoff frequency
RES - Resonance (emphasis at cutoff)

Echo/Delay

TIME - Delay time
FEEDBACK - Number of repeats
MIX - Wet/dry balance

Reverb

SIZE - Room size
DECAY - Reverb tail length
MIX - Wet/dry balance

Flanger

RATE - Modulation speed
DEPTH - Effect intensity
MIX - Wet/dry balance

Bitcrusher

BITS - Bit depth reduction (lower = more distortion)
RATE - Sample rate reduction
MIX - Wet/dry balance

Recording

Record your DJ mix directly in the browser and export it as an audio file.

How to Record

Start Recording - Click the red REC button in the header
Mix Your Set - Play tracks, use effects, and mix between decks
Stop Recording - Click the REC button again to stop
Export - Choose WAV or MP3 format to download your recording

Recording Controls

REC Button - Start/stop recording (turns red when active)
Time Display - Shows current recording duration
WAV - Export as uncompressed WAV file (best quality)
MP3 - Export as compressed MP3 file (smaller file size)
✕ - Discard the current recording

Tips

WAV files are larger but preserve full audio quality
MP3 files are smaller and easier to share online
Recording captures everything you hear through the master output
Make sure your levels aren't clipping (watch the VU meters)

Sample Pads

Create and trigger audio samples from your tracks. Samples are saved automatically and persist across sessions.

Recording Samples

There are two ways to create samples from a playing track:

Real-time Recording: Select a deck, then hold the REC button while the track plays. Release to stop (max 8 seconds).
From Loop Points: Set IN and OUT loop points on a deck, then click "Sample from Loop" to capture that section.

Loading Samples

Click the 📁 button on any pad to load an audio file directly
Supported formats: MP3, WAV, OGG, M4A, and more
Samples longer than 8 seconds are automatically trimmed

Triggering Samples

Click a loaded pad to play the sample (one-shot)
Use keyboard shortcuts: Z X C V B N M ,
Samples play through the master output and are included in recordings

Managing Samples

Click ✕ to clear a pad
Green pads indicate loaded samples
Samples are automatically saved to browser storage
Click the section header to collapse/expand the sample pads

Keyboard Shortcuts

Key	Action
`Q`	Play/Pause Deck A
`W`	Cue Deck A
`P`	Play/Pause Deck B
`O`	Cue Deck B

Sample Pad Triggers

Key	Pad
`Z`	Pad 1
`X`	Pad 2
`C`	Pad 3
`V`	Pad 4
`B`	Pad 5
`N`	Pad 6
`M`	Pad 7
`,`	Pad 8

Tips

Use SYNC to match tempos quickly
Enable SLIP mode before scratching to maintain timing
Enable KEY lock to change tempo without chipmunk vocals
Double-click a track name to see file info