Music for Tablets – XotoPad 2


Presenting an amazingly useful utility program that turns your Windows Touchscreen into a full-featured touch-sensitive MIDI controller.


by Warren Burt, Sept 2016


The Windows platform has been making the transition from pure keyboard-and-screen control to a hybrid of that and touchscreen control for some time now, but what has been lacking, for music applications, is a program that gives one the capabilities of touch-screen controls, as Android and iOS tablets have, for music applications.  German developer FeelYourSound ( ) have now stepped into the breach with XotoPad, which is a program that allows you to set up multiple touch-screen controllers and quickly and easily switch between them.  You can set up keyboard programs for pitch, including isomorphic keyboards (more on that later) with ease, but you can also set up arrays of continuous controllers, switches, sliders, etc. also.  Up to four of these can be programmed and switched between.

For example, one could set up a keyboard tuned to any scale you desired for one screen, then have another screen turning on, say, 10 different sounds (with CC on-off switches) and have volume controls for those sounds below them, then another screen with a customized set of drum pads, and a fourth screen with chords, with each key triggering off a different chord, and each key also having position-sensitive glide controls associated with it.  For those Windows users with touch screens, this will be a boon.  And with the proliferation of Microsoft Surface (TM) machines and machines with similar capabilities, this program has arrived at just the right time.

For example, here’s a 4 octave keyboard tuned to the Phrygian mode.  The number of rows of keys and the number of octaves per row is user specifiable, as is the color scheme for each key.  Sliding one’s finger across the keys produces successions of notes, if the expression control – the asterisk in the upper left of the screen – is off.  If the expression control is on, then moving one’s finger after the initial touch, produces either pitch bends, or glides of a continuous controller, or both.  The user can specify which of these options applies to that screen of keys.  With both pitch bend and MIDI CC control activated, the keyboard can control MPE-capable synths.  This keyboard is in Edit mode, so that you can see some of the controls that you can alter, either on a per-pad basis or for the whole keyboard.  The software provides patterns for over 300 different scales.  If you want other ones, you can define those yourself.

A different use is shown here.  This controller consists of ten on-off toggle push-buttons, and ten corresponding sliders.  The idea would be to have individual sounds triggered off by the top row of toggle-switches, and volume controls for the sounds controlled by the sliders below them.  The sliders are made by selecting an X-Y pad kind of controller, then turning off the X-axis.  This makes a slider with only the Y-axis active.  You could of course have the Y axis turned off and the X-axis active, in which case you get a horizontal slider control.  MIDI CC and its behavior is specifiable for each pad, of course.

And this illustration shows that mixer panel as used in conjunction with AudioMulch, as used in the production of the Tess de Quincey/Peter Fraser dance-theater-multimedia piece  “Moths and Mathematics,” performed in Melbourne and Sydney in early September.  Note the cue and timing instructions that I’ve placed on the on/off switches for each sound cue.


If you’re using the pads to control pitch, you can specify multiple pitches on each pad, so you could get a custom keyboard with each key controlling a custom chord.

There is also a custom chord page, where Xotopad 2 will generate all the three and/or four-note chords in your chosen scale. You can also define a keyboard on one page, and chords on another, then copy and paste the chords into the keyboard page, or vice-versa. This will produce a page where you can have an exotic scale being performed on a keyboard on top of the page, with all the available chords on buttons below the keyboard.

You can either set up a specific MIDI velocity for each pad, or you can set up, for example, the Y-axis to control velocity, so the higher you are on the key, the greater the velocity.  Pads can also act as X-Y controllers.  In this layout below, we have four X-Y pads, each axis of which controls a different aspect of a sound.  Here, the pad on the top-left controls volume and modulation amount of the sound.  The pad on the upper right controls a filter bandwidth and center frequency of the sound.  The lower left pad controls a bit crusher (two parameters), and the lower right pad controls panning and reverb amount.  So on one page, you can have controls for multiple aspects of a sound.

One of the attractions of this software is that it makes available “isomorphic” keyboards to experiment with.  An “isomorphic keyboard” is made by having a grid of keys, each axis of which has a single interval between each pitch in each direction.  For example, a 3-5 isomorphic keyboard would have minor 3rds (3 semitones) between each key on the vertical axis, and a perfect 4th (5 semitones) between each key on the horizontal axis.  In [FIG 4] you can see a D-F-A-C minor 7th chord illuminated in the center of the screen.  Because the keyboard is isomorphic, if you play that combination of keys anywhere on the keyboard, you will still get a minor 7th chord.  And this is the case for any chord.  It will always have the same shape (iso-morphic = same shape) no matter where you play it on the keyboard.  If you want an easy shape for a particular chord, just specify the intervals you want for your axes until you find the shape you want.  For those who want to “try before you buy”, there’s a free version of some of the isomorphic pad layouts from XotoPad available here:


The software is very simple, one could even say basic.  There could be many bells and whistles added to it to make it more subtle and useful.  But it works well, and it makes up in efficiency what it might lack in sophistication.  That is, Lemur (which provides dozens of options on the iOS platform) it isn’t.  But it’s incredibly easy to learn, easy to program and it immediately makes a Windows computer with a touch screen able to act in a similar manner to an Android or iOS tablet.  And the price is right.  In short, I recommend it highly.  I’ve already used this in a couple of pieces, and I’m currently using it to mix sound in the dance-theatre production I mentioned above.  It’s that reliable.  So, for what are you waiting? €35 EUR/$39 USD. Windows 8, 8.1, and 10.  Touch-screen required.


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