Leekboard is an online synthesizing software that uses the advanced
web audio API to play and combine different sounds to a song. Just throw
in your kicks, snares, vocals and other samples and create a song in no
How do I start?
First of all, you need to register a few keys using the button in the top
A popup will appear. Now, just press any key on your keyboard to register
it for playing. It will appear in the top left corner, you can just drag
it aroung on the screen. If you have found a position for the button,
press Save button layout to save its position. However, nothing will
happen yet when you press this key.
When you have registered a few keys, you need to set a sound for every
one of them. Click on one of the buttons you have created and a popup
will appear. It contains a list of settings:
After you have set your sound, you can close the popup by clicking
somewhere next to it in the gray area. Wait for the sound to load(until
the button turns from red to gray) and press the corresponding key on your
keyboard to play the sound.
Like mentioned before, sounds can have different modes:
Repeat repeats the sound until the key is pressed again. If
finish afterwards is activated, the current iteration will finish
playing before the sound stops.
Once plays the sound exactly once. It can be played multiple
times at once by pressing the key again if Repeat on multiple presses
Hold loops the sound as long as you hold the button. Finish
afterwards has the same effect as with repeat.
Sync is a more advanced mode. For it to work, you will either
need another sound that is either in repeat or in song mode or
a metronome. Any sound set to sync will
automatically be cut to fit the length of a playing repeat/song sound or
the metronome and tries to start on matching rhythm. While it waits on
the next beat, the button will be yellow. Finish afterwards has the same
effect as with repeat.
Song plays a complete song in the background. If a sync sound
is started while a sound that is set to song is playing, it will
automatically sync to the beat of the song. This takes precedence over
any sounds on repeat.
Alias lets the button mimic another button which can be
chosen by pressing the for-button. To cancel the process of
selecting a button, press the same button again.
Sequence plays a sequence of events (button
presses/releases). This sequence can be specified in
the sequence settings.
A metronome plays a beat at a given tempo. It is always given preference
over repeating and song sounds when a sound is synced. In addition, a
major beat can be specified to achieve specific rhythms. If Allow sync
only on major beats is turned on, the sounds will only sync to these
major beats. The metronome is not included if a song is recorded.
Just above the settings menu, the sequence editor
can be accessed. Here, sequences of key events (key pressed - key
released) can be specified. To do that, first create a sequence using
the New-button. Sequences can also be cloned
and deleted, but be careful as they can not be recovered once
Once you have created a sequence, events can be added to it. There are two
ways to do this:
Add a single event by clicking the Add event-button and
selecting one of your buttons.
Add multiple events by clicking Record events, playing some
samples as you normally would and pressing the Save-button when
you are done.
If you accidentally added an event, it can be removed using the
corresponding button or the delete key on your keyboard.
After you have added some events, they can be changed by dragging or
resizing. In addition, they can be selected in order to either change
multiple events at once (press shift while selecting) or to accurately
change the start and end of a single event by entering numbers. When you
press escape, the process of moving/resizing or the selection is
cancelled. In addition, the a-key can be pressed in order to
either select or deselect all events.
When moving or resizing events, the can be configured to snap
either to time intervals (specified in seconds) or to other events.
In the bottom right corner, you can open the settings:
You can switch between Button mode and Piano mode. In
piano mode, a keyboard is displayed which can be used together with a
If you turn on live preview, settings like volume,
start/stop, pitch or time displacement are previewed if the sound is
If automatic reload is turned on, sounds are immediately
loaded when you specify a source. Otherwise, they are loaded when you
either press the reload button or you close the settings window. When
the sound is not loaded, previews are not available. However, automatic
reload might use more data so if you are on a mobile network, you might
want to consider switching to manual reload.
If you have a MIDI keyboard, you can turn on MIDI Input. Just
select your device in the drop down list or press the reload button if
it is not displayed.
You can sign in to your Dropbox-account in order to be able
to load your sounds from dropbox. A new button will appear in the button
settings menu that allows you to browse your dropbox-folders and select
a sound file from there.
You can also load sounds from your Google Drive account. The
procedure is the same as with dropbox.
Of course, you can delete all buttons and start over from
If you have a button layout you like to use and want to work on another
computer, you can press Export layout to get a copyable string for
your layout. You can then press Load layout on any other (or the
same) browser window and paste your string there.
When you have gotten used to playing on leekboard for a bit, you may
want to record your own song. This is done in a quite simple process:
Press the record button on top of your screen:
Play your song
Press the record button again
Wait for your song to process
Now you can save your song and share it with everyone else.