The big limitation of piano and all other keyboard instrument is their inability to play other notes, e.g. microtones, quarter-tones, inflections, adjusted intonation, as well as bends, slides, vibrato etc.

This proposal for a piano that can play all possible notes in infinitely small increments has 3 seperate states

1. all-electric. The keyboard is formed from a long thin touch-pad, the same depth and width as a normal piano keyboard. The computer interprets touches according to their longitudinal position on the touchboard. Multi-touch is required to play chords. The computer outputs synthesised tones corresponding to the finger positions.

2. electro-mechanical. The touchboard is as above; but the computer outputs MIDI or similar commands, which are used to drive movable frets and striking hammers on a set of piano strings. The movable frets are servo-controlled metal rollers that slide up and down the string, changing its length. Quick optimisation algorithms position the fret and strike the string to get the required pitch.

3. all-mechanical. I can't quite work this one out yet. I am thinking maybe a touchboard made up of centrally pivoted sprung longitudinal levers, such that the exact position of the finger touch affects lever angle and so can control a left-right swinging arm, which adjusts the position of the movable fret. Perhaps this unit needs repeated 6 or 7 times per octave. How the hammer is also connected into here I'm not sure.
-- pocmloc, Mar 01 2010

Halfbakery: Piano Vibrato Piano Vibrato
Different idea, but related - I like this one too. [zen_tom, Mar 01 2010]

Example of quarter tone notation http://en.wikipedia...Microtonal_notation
Because someone asked in another annotation. [Bootbuckles, Sep 02 2010]

I love option two. Three would also be good - but I too have no idea how you would do it.
-- wagster, Mar 01 2010


Would love to play this, although I'm afraid I'd be constantly out of tune. Can electro-touch pads handle more than one touch input without getting confused?
-- RayfordSteele, Mar 01 2010


It could use the same technology phones do to do multi-touch gestures.
-- jutta, Mar 01 2010


//afraid I'd be constantly out of tune// there is no out-of-tune, only alternative tunings!
-- pocmloc, Mar 01 2010


I like the implementation of using metal rollers (though you could get away with a roller either above/below the string, and not need both?) and I reccon you'd be able to find a method of gearing that in an entirely mechanical manner - perhaps (and this is just the first thing that comes to mind, I'm sure there's a more elegant method) with the addition of another pedal.
-- zen_tom, Mar 01 2010


how does the player know where to put his hand to start a new passage?
-- FlyingToaster, Mar 01 2010


I don't think there's a hardware limitation to the number of points (other than some sort of pixel density). It's basically the same as filming an image - how you interpret the shape you see is up to you.
-- jutta, Mar 01 2010


[Toaster], it would be like singing, violin or trombone - muscle memory and ear-hand feedback. You have to learn it.

Pedals - I wanted to avoid simply adding a pitch bend mechanism to a piano, as that has been done here before. This invention uses lateral position of fingers on the expanse to give pitch shifting. There are no discrete 'notes' to bend.

I have an idea for a harp version, however...
-- pocmloc, Mar 01 2010


Would be easy for violin players, they all say they have perfect pitch.
-- nomocrow, Mar 02 2010


It's times like this we really need bristolz 's wonderful expertize.
-- blissmiss, Mar 02 2010


//they all say they have perfect pitch//
be nice if they occasionally had the *same* perfect pitch at the same time, though.

"Would the first chair please beat the second chair's tin ear into a more pleasing shape"
-- FlyingToaster, Mar 02 2010


The most likely scenario would be example, 1., all electrical. I've always wondered, how does one make this notation in music? The notes on the staff are only those that exist on a piano. So, if you wrote a song consisting of 1/4 and 1/8 tones, how would that be written? Well, it sounds good in theory and definetly something fun to play, for a change. www.pianolessonsnj.com
-- Infinity12, Sep 02 2010


It'd be neat indeed to have a keyboard capable of expressive tuning. I'd go for electro-mechanical with a multiposition "lock" knob or pedal for the most common tunings (and maybe a couple user-programmable) and a position for "freestyle".

If it was digital it'd have to be virtual synthesis and not sample-based because of inter-string resonance.

I wonder how piano teachers tell their students "well all this practising you're doing, it's still not going to sound like how it was written", regarding classical tunings vs. modern equal-tempered.
-- FlyingToaster, Sep 02 2010


Should this not be called an "infinitesimal piano"? An "infinity piano" would run from a sub-sub-woof up to a terahertz and beyond..
-- MaxwellBuchanan, Sep 02 2010


Aren't those the things that cave-dwelling fish have down their sides?
-- MaxwellBuchanan, Sep 02 2010


--The thing to realize is that some of those inbetweeny notes can sound pretty awful.
-- Steamboat, Sep 06 2010



random, halfbakery