Regularly attending events held by the London Hackspace, I was blown away by the demo of the TouchKeys system. Andrew McPherson, working out of Queen Mary, University of London, has put together a kit which a key shaped Printed Circuit Board(PCB) can be stuck onto every key on a midi keyboard, and once wired to the control board and plugged in, can give the exact finger position on the keys. It use the same technology as the touch screens on our phones, measuring the capacitance changes in the circuitry when a finger is introduced in the keys vicinity.
By cleverly segmenting the board in to zigzags and diamonds, and employing the use of dedicated capacitive sensing chips on every key, a high degree of accuracy in finger position can be obtained. Not only that, Andrew has developed the system to have two dimensional sensing, so not only can it know the up-down position but also the left-right position on the key. I almost forgot to mention the system can even interpolate the contact area and have multiple fingers per key!! It’s obvious that Andrew McPherson has really tried hard in making various avenues of interaction available such that the artists using the system can have a multiple ways of modulating the sound. A traditionally one dimensional soundscape has now been transformed into a world with many, it hurts my brain just thinking of the plethora of possibilities.
One of the intuitive ways to map the touch data, and one that Andrew has used in his demos is to make a sliding up and down action to pitch bend the notes, and a wiggle in the left and right creating a vibrato; a recurring slight pitch bend either side of the note. The unnamed notes in between the ones you know are now available to hear. Bending a note up, and its corresponding sharp down, in just the right amount can produce a beat frequency, an interesting sound artifact that composers would rarely put in their pieces as its difficult to recreate with traditional equipment. In choosing the route he did to produce his product, Andrew has made clear he doesn’t want to completely get away from the idea of a traditional keyboard, giving the user responsibility in deciding how and how much they would like to augment their work. Other continuous keyboards do exist such as the notable Seaboard by Roli in which the contours of the keyboard are rippled into the surface of a continuous spongy membrane. This keyboard can be considered completely analogue, meaning you may need to place you’re fingers more strictly to produce the sound you’re expecting.
TouchKeys is on KickStarter! At the time of writing this there are nine days left. It is performing well but still a short distance away from acquiring the funding. TouchKeys has received a great deal of press coverage, many listed on his website here. Have a read of the great thing they say about it! The kit may be a bit expensive, but rest assured it is at an amazing value, there is not any mark-up added to what it costs to produce, the boards have been produce to a very good standard and reliable parts have been chosen to do the job right. If you know a musician who wants to be at the forefront of technology make sure you spread the word and divert them to this page or the KickStarter. It would be a shame if this amazing piece of technology failed to reach the market.