Keyboard Touch and Feel, Position and Orientation

Various internet sources attribute the adoption of the autoharp as a “held” rather than a table-top instrument to one Sara Carter, some time in the 1920s. Sara Carter was part of the Carter family of folk musicians; cousin to Maybelle Carter (mother in law of Johnny Cash). This story might well be true, the Carters certainly added sophistication to the strum/pick variety of techniques, and were likely the first to adopt finger picks over plectrums, which provided a much wider variety of approaches to the string face.

However, this was not an influence on my own determination of optimal playing position; in fact at the outset of the project, when I was not yet steeped in autoharp, and reverse action autoharp lore, I was a little confused, looking at historical pictures, as to what the dominant position was. Further, I gave no thought to autoharp lineage and considered at first (like many other reverse action inventors) that the instrument was novel. Instead I applied the physiological principles learned from a lifetime at the piano to determine a comfortable keyboard position, and similarly applied knowledge from those frustrating years spent attempting to learn the guitar to determine a comfortable strum position. The keyboard position must allow a relaxed left arm, supported from the shoulder and the upper arm, with no twist in the wrist joint, and the strum position must allow free forearm and wrist movement, similarly supported by the upper arm and shoulder. 

Perpendicular keyboard orientation cannot allow both positions to be optimised however the instrument is turned or held — this was the purpose of spending a great deal of time playing “air” harp at the outset of the project. This time determined the optimum playing position and the mechanism evolved from this point. This results in a comparable set of compromises to a guitar — the instrument displays different capability, but similar range in terms of polyphony and timbral variation.

Example image - aligned to the rightMaking an instrument that achieves this guitar-equivalence, but from a keyboard perspective, is perhaps a significant step in gaining market acceptance because there are commercial examples of instruments which demonstrate these design aspirations; the electronic keytar and the guitaro.

The guitaro (shown left) is a limited instrument from a musical and interface perspective, in my opinion. It offers only 22 strings, and is poorly optimised for hand/arm access; but it aptly demonstrates the aspirations of guitar looks and orientation. The keytar similarly provides a guitar-like interface, but with significant compromises from a keyboard playing perspective — the guitar look and feel, set limitations on the hand access.

The ReAPH formulation, admittedly does not look like a guitar. The first and second prototypes were played at a variety of angles (as is the guitar) to test for optimum position, but always in the same orientation. The more upright position, with the keyboard held between the legs in a seated position (reminiscent of ‘cello) became fixed only at the time of prototype 2 because of the broader repertoire engagement (particularly classical) and greater variety of right hand approaches to the strings, and prototype 3 solidified the position by adding the “spitfire wing”, which enables the instrument to rest on the left leg. The resulting instrument may not aspire to a guitar shape, but it is evident to pianists that it will afford a comparable musical interface, and crucially; otpimised playing position for both arms.

The adoption of the raised keyboard position, parallel to the strings, leads to a different coupling arrangement — that of pulley and strings. This is more complicated and arguably inferior to some of the direct coupling actions adopted by the historical inventors (from a mechanical perspective), but it had further unanticipated benefits (we have already explored the potential for cross-coupling to eliminate harmonics); in addition, it allows the two mechanisms; keyboard and damping actions to be considered semi-independently. A key finding of prototype 1 was that slackening the pulley strings slightly and allowing for a certain amount of free key travel (like a piano) produced a better feel to the keyboard. From this finding, I was confident that a keyboard feel, within the range of pianist expectation could be achieved. The direct couplings to damper bars of all save Page are not conducive to experimentation with the issue of free key travel (before the damper system is engaged by the keys); and there is no evidence that anyone considered this. Moreover my analysis of the historical patents leads me to conclude that only Back and Aronis really considered the aspect of keyboard touch & feel to be of significance, and that the remaining inventors just sought optimal mechanical coupling.