Review: Keith McMillen Instruments K-Board Pro 4

Keith McMillen Instruments’ latest keyboard has been a long time coming, but delivers MPE control, a solid build and unique feel for an attractive price.

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Keith McMillen Instruments K-Board Pro 4

Price $895
Contact Keith McMillen Instruments

Keith McMillen Instruments has fast become well known for its innovative and well-designed controllers. It’s made a big impact with a range that includes everything from the K-Board mini keyboard that I reviewed a couple of years back, through to the more colourful K-Mix which covers your mixing, interface and control needs. The company also produces pad and foot controllers, all with a unique KMI look and feel.

Such is the company’s reputation that when it announced a Kickstarter campaign for a
new K-Board around three years ago, it quickly reached its target, although the wait for the
end result – the K-Board Pro 4, on test here – has obviously been a very long one. Happily,
it seems to have been largely worth it…

Board walking

K-Board Pro 4 is what KNI calls an ‘Expressive Smart Sensor Keyboard’ and utilises the same Smart Sensor Fabric technology that is used in other KMI products to give them an expressive feel and with no moving parts. Yes, this is not a traditional keyboard by any standards, although with practice, it can easily be played like one.

It also incorporates the MPE (MIDI Polyphonic Expression) standard that I have had a lot of experience with over the last few years, thanks to ROLI’s various Seaboard controllers – and it seems to be a technology that is being used by more and more software and hardware companies.

Keith McMillen Instruments K-Board Pro 4

It is essentially an extension of the MIDI standard that offers more expressive playing and manipulation over your sounds and incorporates what ROLI and others call ‘the five dimensions of touch’. These are ways of playing notes – and recording the results – and are: Strike, the same as velocity (or volume); Press, the same as aftertouch (or pressure); Glide, a left/right horizontal X-axis control initiated by wiggling a finger left or right, or sliding a controller left/right (think of it as pitch bend per note); Slide, a vertical up/down Y-axis controller, typically used by sliding fingers up and down the keys; and finally Lift, which is the speed at which your finger leaves a key – great for getting fast pluck effects. So we’ve got a slick look, innovative design, KMI’s expressive playing, the latest MPE compatibility and a keen price. What’s not to love, right?

No moving parts

K-Board Pro certainly feels ‘pro’. It’s solid and weighty with a rugged aluminium construction, and lights up, although not as much as other KMI products. Secretly, I was hoping for the more illuminating experience of the K-Mix, but only the four programmable slide controllers are backlit, which is a shame.

As to the feel of the keyboard, this might take some getting used to for players. There really are no moving parts here, so the experience can’t be described as a keyboard ‘action’, as such, that you’d get on a fully weighted keyboard. Here, there is a slight give on the white keys, more so on the black. But the keyboard itself is surprisingly playable, just a little different, although not the more alien, silicon experience offered by ROLI.

Keyboard experiences are very personal, so I’d always suggest trying a new one out like this. It takes a bit of getting used to, but I like it. I start out trying K-Board out with Korg’s Gadget that I happen to be testing at the same time. Expecting K-Board to play Gadget like a normal controller, I was surprised to see it change the filter frequency of the first Gadget I loaded with the Slide control – Gadget is MPE-compatible, it seems. Who knew? (Well,
not me, obviously!)

One synth I know definitely is MPE compatible is ROLI’s own Equator, so this is next on my list to test K-Board Pro 4 with. Equator is a synth that was largely designed to show off how expressive ROLI’s keyboards can be when using their MPE features, so comes loaded with some great sounds that can be tweaked using the five dimensions of touch to sound ultra-real or completely out of this world.

Keith McMillen Instruments K-Board Pro 4

I’m happy to report that K-Board Pro 4 plays the Equator synth easily as well as ROLI’s own hardware, with all of the articulations of the acoustic and not-so-real sounds coming through. The five dimensions of touch are clearly doing their thing on Equator’s UI as I step through the sounds and the overall playing experience with K-Board is as expressive and nuanced as you could wish for.

What you might find using MPE controllers on standard synths is that they can be rather confused if you start chucking MPE data at them – you might get the odd drop-out as the software struggles with extra data it’s perhaps not used to.

It might be best, then, to use K-Board in non-MPE mode (which you can select in the free editor – see below) when using such software. It certainly doesn’t happen with all non-MPE synths – FM7 played back fine in either mode – but the option is there should you need it.

Pro editing

And talking of the editor, this is an excellent free download for Mac (72MB) and PC (54MB). As well as toggling the aforementioned MPE Mode, the software allows you to alter a number of other parameters and create keyboard setups, and it’s well worth detailing some of its other functions. First up, you can set up how the X-axis (wiggle), Y-axis (Slide) and Z-axis (press) parameters function, adjusting parameters such as Gain and Threshold.

Keith McMillen Instruments K-Board Pro 4

The four main lit-up sliders can be programmed under the Sliders & Pedals tab, which also gives you access to what optional pedals can control, for which the K-Board has two slots. The four Sliders each have drop-down menus to select one of eight different functions that they control (including preset selection and assignable MIDI CC) and over which keyboard zone they control it (Upper, Lower or both).

A third tab, Advanced, gives you access to parameters like Pitch Bend Slider Range and Transpose functions. You can save all setups that you make and overall, the editor looks great – with a virtual keyboard showing which notes you are hitting and sliding – and functions well.


K-Board Pro delivers MPE and style in large amounts. Its price is keen, although the street price of the ROLI Seaboard Rise 49 (see Alternatives below) puts it in direct competition. If MPE is what you are after, it’s a straight slog between the different playing styles of these two – and the winner will be totally down to you, as these really are keyboards that are different from traditional controllers so you’ll need to experience them before buying.

Overall then, this is another innovative controller from Keith McMillen Instruments that maintains its design flair and taps into the MPE standard for some brilliantly nuanced playing.

Do I really need this?

K-Board Pro 4’s big pulls are its innovative design and MPE compatibility. You might have been tempted with the latter by ROLI’s extensive range of products and perhaps been put
off by their arguably unusual feel. If that’s the case, then K-Board Pro 4 will give you a different but equally versatile playing experience. Having a controller that looks a little different can also be a draw – it is for me, anyway.

Yes, I know looks should take second place to functionality, but the music-gear world can be very black and bland (albeit less so recently) and something that looks good and plays well can always be an attractive proposition. If you have a more standard controller that you are happy with, then this may not be essential, but it does make MPE accessible and fun.

Key features

● MPE ’Expressive Smart Sensor Keyboard’ controller
● Four octaves of Smart Sensor keys
● Plug ’n’ play and USB powered
● Responds to five dimensions of touch – Strike, Press, Glide, Slide and Lift
● Rugged aluminium construction with no moving parts
● USB and MIDI Expander outputs
● Comes with Bitwig Studio 8-track
● Software editor included
● Requires Windows 7 or Mac OSX 10.9 or later, Pentium 4 processor


BLOCKS from £155

There are several other companies adopting MPE control – from Modal to Linn – but the cheapest way in is with ROLI and its BLOCKS, which even include a Seaboard keyboard (£225) for the MPE experience in miniature.

Read our full review here.

Seaboard RISE 49 £860

This is more of a direct alternative, with the full-sized ROLI 5D touch and soft-silicone experience in a solid keyboard that comes with many extras like the fabulous Equator synth. It’s a different feel but worth trying out.

Read our full review here.


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