PercX Manual


The Edit Page lets you edit and completly customize an intruments rhythmic pattern. These patterns are small MIDI clips that trigger samples from a multisampled instrument. The "drum roll" in the center of the Edit Tab shows the rhythmic pattern of the selected track on the x-axis and the Round-Robin index of the instruments samples on the y-axis.

It also features a lot of tools to edit these MIDI clips as comfortably as possible. In this regard it is not intended to replace a DAWs Midi Editor but to assist in quick & dirty variations and adaptations of rhythmic material focussed on the key features of the PercX Engine (pre-roll- and round-robin aware, velocity-modulation).

Track Edit Controls

At the top of the edit track you can see a truncated version of the Mix track controls of the selected track. With Pan, PowerButton, Volume, Shaping and a small version of the Dynamics knob.

Use the Dynamics Knob in the Edit Tab to see the effect of its relative velocity scaling (white over grey) on the Velocity display in the Edit Window.

If you multi-select [Ctrl or Shift + click] different tracks the track-name will display the last-selected track-information and waveform with a little "+" icon that show the number of additional selected tracks.

Variation - Allows you to store up to four different MIDI patterns variations. When you click on Variation 2 it will copy the current pattern into the second variation slot.

With a right-click you can delete or reset the variation or create keyswitch controls to switch between the variations with a keyboard key.

Bars and Time - Allows you to adjust the length of the loop in number of bars, along with the time signature of the bars. You can create any time signature that you want in this way.

You can achieve a broad spectrum of rhythmic variation when you change the timing of an individual track against its neighbors. In PercX each track has its individual play-back position. You can observe this with the shifting speed of different playback-bars on the Mix page.

Edit Modes - The three edit modes are the main tools to edit the notes in the drum-roll.

  1. Select Mode [1] - Click on a note to select it. Drag a selected note to move it. You can shorten/lenghten a note with a handle on the end of the note. Start draggin in empty space to draw a selection zone to select multiple notes. As it's common: You can delete selected notes with the [DEL] key.
  2. Pen Mode [2] - Click on emtpy space to create a note. Click and drag to lengthen that note (this will snap to the active raster). Click on a already existing note split the note according to the active raster. Right-click a note to delete it. Right-click in empty space to drag a deletion zone and delete every note in it.
  3. Play Mode [3] - Click on a note with the right-ward facing peak of the play-button triangle to prelisten the note. Click anywhere on the window to start the global play position from there. (Great to prelisten to passages that you're editing right now.)

Shortcuts: The Pen Mode and the Play Mode each have an additional shortcut to the 1/2/3 keys. When you're in Select Mode. You can toggle these modes with [Ctrl]Play and [Alt]Pen.

Window display options - The display options show four small icons that toggle the different parts of the Track Edit Window on and off. Drum-Roll, Velocity-Bars and ENV-Table. Only the Auto-zoom does something different. It toggles the auto-zoom mode to reduce the y-axis when zooming into the Edit window.

Track Edit Window

In the center of the Edit Window you can see the Drum Roll. It shows the MIDI notes of the currently selected rhythm with the distinction that the y-axis represents not pitch but Round Robin samples.

On top of that you can see three distinct elements: The Single-Row that reduced the 2D Map to only the rhythmic dimension. (You'll also see this featured when selecting multiple tracks), the Loop-Zone with which you can shorten the instruments loop, and the waveform that you know from the Mix Page.

Under the Drum-Roll you can see a Velocity Slider belonging to every note. You can drag it up & down to change the velocity of each note. Right-Click and drag on the velocity sliders row to draw a straight line into the velocities.

When you open the ENV-Table in the Window display options a new row with an Envelope Table will appear. This table can used in conjunction with the Automation Matrix .

Multiple Track Edit

When you select many tracks or use the ALL Button, the window will collapse all up-to-eight tracks into one single-row display of all tracks. All Edit Modes also work in this view.

Because its kind of difficult to select notes in a too crammed view in Select Mode there's an additional shortcut: If you hold the [Shift] Key down, you can drag a selection zone from anywhere (Even if you're hovering a note). This is very practical if you want to move whole parts or cut holes into an arrangement.

Track Edit Tab

At the bottom of the Edit Window you can find the Edit Tab.


The controls here allow you to create, save and load patterns into the selected instrument track. Selecting new pattern will clear the existing one and allow you to create a new one from scratch. Patterns can also be saved and loaded, and revert pattern allows you to re-load the default, preset pattern for the instrument currently loaded into that track.


The record function allows you to record your own patterns in by simply playing them in with your MIDI controller.

The record function works as follows.

  1. Activate record mode by clicking on the REC button. The control and piano roll will turn red signalling that you are now in record mode. You will notice that the keyboard footer now also also has a small red target on two keys, the same note, an octave apart. Both the original key used to play that instrument track, and an extra key one octave below can now be used to play this instrument in record mode.
  2. Try and play these keys, you will notice the instrument is now fully playable by you, the same way it would be in manual mode (see here).
  3. In order to start the recording process, you will need to hold down any other key without a red target on it, and you will also hear a click/metronome begin as a rhythm guide. The click can be turned on or off by clicking on the metronome icon, and turned up or down with the slider beneath.
  4. Once you hold down another key, you can play in your own rhythms and patterns using the red targeted keys. As soon as you press one of the record keys, recording will begin (indicated by a stronger shade of red), and the pattern will continue to loop until all keys (except the record keys) are released. If you are unhappy with your recording take, simply continue to allow the pattern to play until it loops back, and you can record something in again, overwriting the previous take automatically.
  5. When satisfied with your recording, turn off record mode.

After recording, in order to quickly clean up your pattern and avoid any unnatural RR repetition, simply select all notes, click "fill gaps", followed by "distribute RR".

In seldom cases "Quantize" may also be appropriate :)


Distribute RR will automatically move notes which use the same round robin/sample to different samples, to provide an easy and quick way to remove all potential unnatural duplicate/repeated samples from sounding.

Duplicate - Duplicates the selected notes immediately to the right of the selection, overwriting the pre-existing material.

To quickly duplicate your groove and get it sounding natural, select your groove, duplicate it for the full length of your loop, and then select all (CTRL+A) and hit "distribute RR" to ensure that the repeating pattern uses different samples each time to prevent it from sounding artificial and robotic.

Fill Gaps - Fills the gap between the notes.

Double/Halve - Converts the selected notes into either double or half their time.


Grid - Turns the grid on or off. Adjust the slider to add swing to the grid.

Raster - Select a raster that the current rhythm should snap to. The raster is set to 1/16 by default.

Humanize - This function allows you to add slight random offsets to the position of midi notes. To use this function, first set the intensity with the slider, and then click the icon to apply.

A great scenario in which the humanize function could come in handy is if you hav a lot of instrument tracks playing the same rhythm. Unless they are ensembles with natural flam, they may be so snappy and perfectly timed that they sound unnatural and robotic. To fix this and make it sound more real, simply select all the stame with the same pattern (CTRL click each stem), select all notes (CTRL+A) and apply humanization to taste until the sound has a nice natural amount of natural and random flam.

Quantize - The opposite of humanize. This function allows you to quantize the start positions of notes to the grid lines, at varying intensities. Set the quantization intensity first (100% is full snap to the nearest gridline), move the slider, select the notes you wish to quantize, and click the icon.

Automation Matrix

The Automation Matrix takes input from two track specific modulation sources and applies them to up to five different aspects of each track. Click on the matrix crossing-points to add the modulation values to their destinations.

The Velocity row takes the Velocity values of the currently selected track as input. You can route this values to Volume, Pan and the three Shape FX slots. Theres a little RND slider that lets you add a randomization amount to the modulation (try it with HiHats and PAN..)

The Envelope row takes the Track Envelope modulation as input (You can open it by clicking on the little ENV icon on the top right of the Window Display options). You can use it to automate fades etc.. on track level.

Drag to DAW

The 1.2.0 update added the ability to create and drag MIDI clips from PercX to your DAW. This is useful for two use cases:

  1. You prefer editing the MIDI in your DAW. Since the playback engine in PercX is loop-based, some composition & editing styles that may require a more linear technique tend to be difficult to achieve inside PercX. In this case you might want to drag & drop the MIDI data out of PercX onto the track in your DAW that contains PercX, to power it from the outside.
  2. You want to layer / double some patterns with other sound sources. Therefore the drag target will be any other virtual instrument plugin / sampler.

There are various options for customising the content of the MIDI clip that you will drag, but most of the options are suited for one of those two use cases.

In order to access the drag and drop functions, click on the Drag icon in the Edit tab and you'll see these tools:

Just select one or more tracks that you want to "export" (or press the ALL button to select all tracks), then start dragging one of the two big buttons outside of PercX' interface (to the DAW or Desktop). Each button will create a different MIDI clip out of the instruments pattern data and the easiest way to explain this is to look at the MIDI file itself:

Trigger Mode

The trigger mode will just create one single note that has the exact same duration as the pattern in PercX. This is being used to trigger the track in PercX. It's not a "real" MIDI export with all the instruments pattern data but rather an extremely handy tool, because the days of creating/recording these MIDI trigger clips yourself in the DAW are finally over.

Be aware that if you have selected all tracks, the MIDI clip will just contain the single C note that is used to trigger all tracks at once.

Pattern Mode

Now the pattern mode would be what you expect from a MIDI drag 'n drop function: it contains the pattern of each selected track as distinct MIDI notes including velocity and duration. If you want to drop this MIDI clip on the PercX track itself, PercX needs to bypass its playback engine and react on external MIDI input. Therefore, all tracks that have been included in the export will be automatically switched to Manual Mode .

If you don't want PercX to automatically switch to Manual mode (eg. because you drop the clip on another track), you can deactivate this by clicking on the Switch after Export button on the left. If you're using one of the mapping modes suitable for external sources, this option is automatically deactivated.

Prerolls and MIDI export

As you probably know, PercX automatically handles the prerolls for each sample automatically. You can read more about this feature and its implications here, however it's important to understand that the MIDI clip from the Pattern mode export cannot be guaranteed to sound exactly the same as the pattern inside PercX:

All prerolls are completely truncated for each track so that the MIDI notes will always be on the "hit". This is necessary in order to ensure the correct timing because there are tracks with varying amount of preroll time. However this truncation can have a drastic impact on the sound of the track and some FX tracks that have a reverse buildup will get completely silent.

There is no way around that problem except for not using the Pattern Mode for tracks with a high preroll time.

In this case that particular track is exported it the same manner as the trigger clip mode: it will just contain a note that triggers the playback inside PercX. The other tracks are exported as patterns.
By default, PercX uses a sensible default that detects tracks with prerolls and automatically switches to trigger mode for tracks with high prerolls. You can always see which track is being exported in which mode using the indicators below the drag icon. If you load up eg. Achilles, you will see this setting:

and if you drag the Pattern clip to a DAW, it will look like this:

so as you can see, the first track (B2) is a single note while the other tracks are being exported as proper MIDI patterns.
You can change which tracks should be exported in which mode by using the Preroll Threshold slider on the left:

Changing the slider will update the icon indicators in realtime so you can always see how this setting will affect the track export.

Note Remapping Matrix

If you're using the MIDI export in order to trigger sounds from an external source, the chances might be high that the MIDI notes which trigger the tracks in PercX do not match the notes that trigger the sounds you want.
You can of course manually edit the MIDI output in order to match these notes, or you can use the note remapping matrix that will do this automatically.

Be aware that the remapping matrix only affects the MIDI clip generated when you drag the icon and will not change the actual mapping in PercX.

There are 5 modes that cover most use cases that you can select by clicking on the Mode icon:

Icon Name Description
PercX The default mode that maps each note to the default note.
Deinterleaved Maps every odd track an octave below in order to improve the editibility of the MIDI clip (see below).
4x4 Maps the notes to the default 16 pad arrangement so it can be used by drum machines like the MPC (or the Ableton live drum rack)
GM Maps the notes to match the usual GM Midi mappings for drumkit (more or less)
Custom A user defined mapping to match any arbitrary MIDI target.

The first two modes are intended to be used to export MIDI to the PercX track itself, while the other modes are used for exporting the MIDI pattern to an external target.

You can take a look at the note numbers in the matrix pads in order to see the effect of the different modes.

Deinterleaved mode

The second mode is a bit special and deserves some explanation. By default, PercX uses consecutive note numbers for each track, starting with B2 / B3 downwards until E2 / E3. However if you export a full kit in the default mode, it will look like this:

Since the notes are chromatically ordered, there is no space inbetween them which makes editing the clips a bit tedious (selecting a certain range might be annoying depending on your DAW).

The Deinterleaved Mode addresses this issue. As you might know already, the manual mode adds a second note one octave below (or aboeve for Player B) that triggers the same note so you can play flams and rolls. The mode just uses this "secondary" note for every odd track in order to make some space between the tracks. The same rhythm looks like this:

There is absolutely no difference in sound, but the order of the notes is a bit messy:


instead of


However the space between the notes makes the editing much more easy. So if you intend to edit the MIDI clips afterwards, using this mode might yield a better workflow if you can live with the inconsistent order of tracks.

Custom Mode

The custom mode lets you map every track to any arbitrary note to match your external source:

  1. Select a single track (either by clicking on the row or clickin on the "pad" in the matrix)
  2. press the Learn button
  3. Press any key on your MIDI keyboard

or alternatively, select the respective note directly in the context menu of each pad.

As soon as you have changed one note, the mode will be automatically set to Custom.

You can load / save / clear custom mappings as XML file by clicking on the mode button and choose one of the export options at the bottom.