Discover ROLI Piano’s four Dimensions of Touch
A handy guide to MPE gestures on our most expressive piano keyboard ever
Our flagship piano keyboard, ROLI Piano, is on its way (and early batches are selling out fast!). So, in anticipation of the first keyboards shipping, we thought it’d be the ideal time to recap some of ROLI Piano’s most expressive features.
The first thing you’ll likely notice about ROLI Piano is the RGB lighting on each key. What we’re interested in here however, is a little less obvious, at least until you start playing. We’re talking about ROLI Piano’s four Dimensions of Touch.
"4D Touch”, pioneered on Piano M and now perfected for the full-size ROLI Piano, is our implementation of MPE (MIDI Polyphonic Expression) for piano keyboards. MPE, in a nutshell, means sending MIDI information on a separate channel for each and every note you play. This means you can add the same — or an even greater — amount of expression for each note individually as you’d normally be able to for all the notes you’re currently playing.
Consider a three-note chord, for example. On an acoustic piano, you can play each key harder or softer, affecting the balance between each note. Standard MIDI controllers and synthesizer keyboards behave similarly but often add pitch and mod wheels. These give you the ability to bend notes up or down or modulate your sound — by opening a filter for example. The limitation of these controls is that they apply to all three notes equally; the whole chord will bend up or down, and the filter opens for each note in the same way.
With 4D Touch, you can bend each note in a different direction, to a different degree, at different times. You can also, to give just one example, open up the filter for each note separately. It’s a little like having a separate pitch and mod wheel for each and every key, though playing with 4D Touch is more intuitive in practice. Rather than using your other hand to manipulate pitch or mod wheels, you express yourself through natural gestures with each finger as you play.
Read on for a rundown of how each Dimension of Touch works, together with a short video demonstration and some examples of good potential uses for each. We’ve also included a bonus guide to the Dimensions of Air that you can unlock by pairing ROLI Piano with Airwave.
Strike
Strike works like velocity on a piano keyboard. It’s how fast you press a note (what we commonly think of as playing harder or softer). Normally this would be assigned to the volume of a sound: faster means louder.
With the expressivity opened up by 4D touch, however, you might find more creative uses. Striking harder to create a shorter attack feels very natural, for example, and you can map additional parameters too: perhaps causing effects to trigger more strongly on louder notes, or subtly opening a filter (mimicking the tendency of louder notes to sound brighter on an acoustic instrument).
Press
Press is also known as polyphonic aftertouch. It doesn’t strictly require MPE, but it is still relatively rare on non MPE-compatible keyboards. Press is a measure of how hard you press a key down after the initial velocity registers. You can push the key further down into the keybed to varying degrees to modulate whatever aspect of your sound you like.
A common mapping for Press is to the aforementioned filter cut-off of a synthesizer, but it has many more uses. Press is perhaps the most important Dimension of Touch when it comes to emulating expressive acoustic instruments with ROLI Piano; consider the ability of a violinist or flautist to vary the timbre of a single note over time. Press allows you to do the same thing, independently for multiple notes at once.
Glide
Glide is where a lot of ROLI Piano's magic lives. If you’ve played a high-quality, semi-weighted keyboard before, the previous dimensions ought not to feel too unfamiliar. Now imagine that, instead of just moving up and down, your keys could pivot from side to side as well.
That’s Glide. Effectively, it’s polyphonic pitch bend. You can now add vibrato with a wiggling motion, just like on a stringed instrument. With a little practice, you can bend between notes, even within a chord, turning a minor chord major with a slight shift of a single finger, for example. In practice, many players find that subtle use of the Glide dimension allows for a great deal of added expression and sonic movement — particularly useful when emulating the sound of an acoustic instrument.
Lift
Lift is less about how you play a note and more about what happens after you stop. It's the opposite of Strike, in that it’s a measure of how fast you take your finger back off the key again. This is also known as release velocity.
What can we use it for? There’s no one default here, and experimentation is encouraged. You’ll often find Lift used to add resonance, reverb, or delay to the end of a sound, but you can also use it to trigger entirely new sounds.
A common application for this use is acoustic instruments that make a distinct sound when a note is released. Good virtual pianos, for example, will typically include “release samples” — separate recordings of the sound each key makes when it’s let go and lifts back up. In this case, a faster Lift gesture can be assigned to trigger a louder release sample.
Add Airwave for even more dimensions of expression
ROLI Piano and Airwave have been designed with one another in mind, and the pairing of the two makes for an incredibly flexible and expressive keyboard setup. Powered by ROLI Vision, it tracks both of your hands in 3D space above your ROLI Piano Keyboard, allowing you to use a range of natural gestures to further sculpt your sound.
Here’s a quick summary of what each of Airwave’s Dimensions of Air adds to the ROLI Piano playing experience.
Air Raise
Air Raise is the primary Dimension of Air. Like a conductor raising her arms to lift the energy of an orchestra, Air Raise is ideal for grand gestures and not-so-subtle increases in intensity. Use it to add volume, fade in new layers, and generally amp things up.
Air Tilt
Air Tilt is a rotation of the wrist, and it’s great for things you need fine, real-time control over. From filters to drives to effect levels and more, Air Tilt is an expressive alternative to more traditional synthesizer knob twiddling. It’s often used in conjunction with Air Raise.
Air Glide
Air Glide looks a lot like ROLI Piano’s physical Glide gesture, but it has different uses. Rather than bending pitch up or down, Air Glide alters the sound of the notes you’re already playing on ROLI Piano. Given the expansive gestures involved, it’s a great fit for stereo effects and anything that increases or decreases a sonic sense of space.
Air Slide
If you’re familiar with Seaboard, you may have noticed that ROLI Piano features four Dimensions of Touch to Seaboard’s five. The additional dimension you’ll find on Seaboard is Slide, which is a forward or backward movement along each key. Via Air Slide, Airwave gives us a way to add an approximation of Seaboard’s Slide abilities to ROLI Piano too. Moving your hands from above the front edge of ROLI Piano’s keys towards the back, or vice versa, is a great way to modify sounds produced by other gestures.
Air Flex
Air Flex is about the angle, upwards or down, of your hands at the wrist. It makes a great, subtle, addition to gestures you’re already making in the air. By assigning Air Flex to the balance of two different layers, for example, Air Raise can now be used to create a much wider range of sounds; you might fade in only sound A, only sound B, or any mix of the two.
Air Grasp
We're constantly making updates to Airwave, and the newest Dimension of Air to make the cut is also one of the most intuitive. With Air Grasp, you can cut a sound completely by closing your fist, which makes for a great dramatic ending. Opening and closing your hand is also an intuitive way to create stuttering staccato rhythms.
Save on ROLI Piano
ROLI Piano preorders are open now, and you still have time to get a great deal. Order now to save $200 / £180 / €200, or unlock all of the dimensions above with a ROLI Piano and Airwave bundle, currently with $300 / £250 / €300 off.
