Reimagining The Keyboard: Alternative MIDI Controllers for Expressive Performance

The 12-note musical keyboard has remained largely unchanged since the 14th century. Arguably this is because they got it right the first time. Even today it fits the needs of most keyboard customers who walk into a music store: They’re looking for a piano to learn on, a do-it-all synth for their weekend cover band, or a note-entry device for computer music-making.

However, some synth-focused musicians have long felt that the traditional keyboard under-utilizes the power of synthesizers and virtual instruments. Even a pretty basic synth offers lots of parameters that can mold the sound in real time. However, the musical interface – the keyboard – offers relatively few means to affect those parameters. Synths make up for this with other controls you can grab, and sequencers and LFOs can add animation to the sound. But for playing synthesis like you play notes, the black-and-white slab remains fairly limited. What’s more, what you can do usually affects all currently heard notes at the same time. Wouldn’t it be great to add expression note by note?

A passionate group of hardware manufacturers thinks the answer is yes, and has answered this call with MIDI controllers that rethink what the keyboard is supposed to be. Likewise, a growing number of software instrument developers are working to optimize their products to take full advantage of the increased musical expression these controllers offer.

One half of the equation here is Multiple Polyphonic Expression (MPE), a.k.a. “Expressive MIDI.” Basically, it’s a way to use the existing MIDI spec to get a synthesizer to do things to individual notes – bending, adding vibrato, brightening up the filter, or really anything – based on some way in which your finger is interacting with the key. The other half of the equation is mechanical: A controller has to be able to sense types of finger interaction on a per-note basis: aftertouch, where the fingertip is actually touching the key surface (in terms of both X and Y axes), and more. The good news here is that because manufacturers are collaborating and the whole thing doesn’t use any proprietary messages beyond good old MIDI 1.0, performance should be consistent across brands and across different supporting soft synths. Retail-wise, differentiation is about how they look, feel, and play physically, which is how things should be!

Haken Continuum

The Continuum is the grand dame of alternative expressive controllers. Its first commercial sale was in 1999(!) as an input device for the highend Kyma sound design system. Not only is it still made today, but it has a large and loyal enough user base that the first music convention dedicated to it, ContinuuCon, happened in June of this year in Asheville, North Carolina.

Unlike a conventional keyboard, its neoprene playing surface is continuous (hence the name) and could rightfully be called the first “fretless keyboard.” Underneath this is a matrix of magnetic sensors that allow it to detect finger pressure, X position, and Y position – all with true per-note polyphony. (In fact, it’s been capable of this since well before MPE existed.) Experienced Continuum players like Chris Stack and my fellow music tech journalist Geary Yelton tout its resolution as well, which is still among the highest in the business.

Though part of its original appeal was that it could be set up to play microtonal scales, the familiar chromatic keyboard layout is indicated by the subtle stripes which indicate the positions of the “black keys.” Musical benefits include being able to glide between notes without lifting one’s fingers, apply bend or vibrato similarly to a guitarist, and use the pressure and Y-axis for, well, anything you’d care to assign. For example, pressure could increase filter cutoff while vertical position morphs the sound between different waveforms.

The Continuum also offers internal sounds via its Eagan Matrix synth engine, which is of course hyper-optimized for its hardware. Included editor software lets you customize your control assignments and set up templates for soft synths. The only downside is that it’s a handmade, boutique instrument with a price to match: $5,290 for the full-sized version (about seven and a half octaves) and $3,390 for the half-sized (about three and a half octaves). For this reason it has been more in the purview of direct sales than retail placement, but no discussion of expression-enhanced MIDI controllers is complete without it. | hakenaudio.com

Roli Labs Seaboard Grand and Seaboard Rise

Relative newcomer Roli has been making a lot of waves. Actually that’s literal, because “Keywaves” is what they call the keyshaped undulations on the playing surface of their Seaboard line. The concept is similar to the Continuum, but where it’s a flat surface with solely visual cues as to where conventional keys would be, the Seaboards provide tactile feedback via those bumpy Keywaves. It’s still easy to glide around without lifting your fingers, but playing the Seaboard as though it were a piano or organ is somewhat easier for traditional keyboardists. Doing nothing but that is a waste of its abilities, but the point is that some familiarity in look and feel lowers the barrier to entry.

The Seaboard Grand debuted first, and comes in 37, 61, or 88 keys. It offers four dimensions of touch, all with per-note polyphony: velocity, aftertouch, X-axis finger position, and release velocity. (In Roli’s parlance: Strike, Press, Glide, and Lift, respectively.) The flat areas of the playing surface above and below the Keywaves serve as ribbon controllers that let you do big portamento sweeps, but the Grand’s keys don’t sense Y-position. It’s also a self-contained hardware synth with internal sounds thanks to its Equator sound engine. You select presets via the minimalist “Sound Dial,” and can do much deeper editing by connecting to a computer. Notably, the Equator editor window has panes that let you determine which sound parameters respond to the various touch gestures and how. Beyond specs, one cannot overemphasize the overall impression of quality and futurism the Seaboard makes on a first-time user: The playing surface feels fantastic – you just want to keep touching it – and the whole unit seems carved out of a single block of some space-alien material.

The Seaboard Rise (shown) is the more affordable follow-up, but it’s more its own instrument than a “lite” version of the Grand, and actually adds some features. It does sense Y-axis position (“Slide) in addition to all the dimensions of touch of the Grand. To the left of the Keywaves is a cluster of useful controls, including an X/Y pad and three sliders that set the sensitivity of Glide, Slide, and aftertouch. This is especially useful with Glide; there’s a definite technique to hitting proper pitches and shallowing out the sensitivity really helps traditional keyboardists feel they can master the instrument. What do you give up on the Seaboard Rise compared to the Grand? The Keywave surfaces are about three-quarters the size of the Grand’s. And, it’s a controller only with no internal sounds, but instead comes with a soft synth version of Equator you can run on your laptop. For iOS devices, you can download the free app Noise, which includes all the Equator sounds but has a parameter set focused on live performance. You can play Noise from the Seaboard or right on your device’s touchscreen. The Seaboard Rise is available in 25 or 49 keys for $799 or $1,199 respectively.

CEO Roland Lamb is really out to establish a new milestone in the future history of the keyboard. He’s also fond of pointing out that the piano itself was once considered radical compared to the harpsichord and organ. When you hear what a Seaboardist can do with a bit of practice, you know he’s onto something. | roli.com

Roger Linn Design LinnStrument

Though he’s most famous for inventing the modern drum machine, Roger Linn is both a guitarist and a huge advocate of alternative controllers. That’s why the LinnStrument, which I reviewed in Keyboard magazine in June 2015, departs from a piano-like layout and instead uses a grid of 200 note squares arranged in eight rows of 25. Though the squares have tactile borders, the overall surface is continuous so pitch gliding is no problem. You can set it down in front of you, but Roger’s preferred way to play is to strap it on like a guitar with the left hand approaching the playing surface from the rear and the right from the front. The LinnStrument is a controller only, with no internal sounds, but can be USB bus powered.

Each square senses X and Y position as well as velocity and aftertouch and, again, all with per-note polyphony. As on all the controllers we’ve looked at so far, X is intended for pitch, Y defaults to filter cutoff (brightness) or modulation, and pressure is for modulation or expression, though of course you can re-assign things. The note layout is chromatic from left to right, and in guitar- like fashion, ascends in fourths within any column of squares.

Notably, the squares light up. By default, C is blue and the rest of the C major scale is green. (You can reprogram the LinnStrument to display any scale you like.) Touch a square, and every other one that plays the same pitch turns red. You can split the playing surface into two zones to play different sounds, and retask the bottom row to act as a ribbon controller or trigger things like strums and the built-in arpeggiator. We’ve only scratched the surface, which is all we have room to do here.

One of the LinnStrument’s big advantages is that chords and melodic lines have the same physical shape in all musical keys: Learn something in C and you can play it in F#. That can’t be said of the piano, and though I’m a keyboardist, I wrapped my head around Roger’s machine very quickly – and had fun. In practiced hands, the LinnStrument is uncannily expressive on sounds such as saxophone and acoustic guitar. Its best customers will likely be not only guitarists, but anyone who wants an expressive way to interact with synthesis but isn’t necessarily invested in a keyboard layout. Its typical street price is $1,499. | rogerlinndesign.com

Keith McMillen Instruments QuNexus and K-Board Pro 4

The $179 QuNexus may come in at the more affordable end of our spectrum here, but it’s not lacking in power. It looks like an ultra-slim two-octave controller keyboard made of drum machine- like pads, and that’s certainly where it starts. The keypads feel very good, responding to finger pressure very smoothly. Each pad senses velocity, pressure, and what McMillen calls “tilt,” which functions mostly like Y-position sensing. All these are pernote polyphonic. Because these are separate keys, left-and- right gliding isn’t implemented like on the Continuum, Seaboards, or LinnStrument. Instead, a dedicated pitch-bend pad resides at the lower left corner. In addition to USB MIDI (bus-powered, natch), the QuNexus directly outputs CV/gate signals, making it a great controller for anyone just getting into Eurorack synths. Adding KMI’s MIDI expander box ($59) is how you hook it up to gear that uses 5-pin MIDI ports.

Though not available yet for retail sale, the experimental “Labs” section of McMillen’s website teases the compelling K-Board Pro 4. I got my hands on a prototype in San Francisco recently, and it aims to provide Seaboard-like multi-dimensional control in a more traditional keyboard form factor. The four octaves of discrete keys sense velocity, aftertouch, X position, and Y position, all polyphonically. Four horizontal ribbon controls above the keys (arranged end to end) are freely assignable. Keep an eye out for this one. | keithmcmillen.com

CME Xkey and Xkey Air

These almost weren’t included as they don’t offer the multiple means of expression of the other controllers in this roundup, but the slim and sleek Xkeys deserve an honorable mention for one big reason: They offer polyphonic aftertouch, which not so long ago was the exclusive domain of pricey bucket-list synths like the Prophet-T8 and Yamaha CS-80. These may be “chiclet” keys, but they’re the best chiclet keys I’ve ever played. The 25-key length ($99) disappears into my laptop bag and goes with me everywhere. Need more real estate? The 37-keyer ($199) tucks nicely into a carry-on sized airport roller. Add $100 to either of those prices and you get the same length in the “Air” version, which adds wireless Bluetooth connectivity to your computer or mobile device. | cme-pro.com