Of course – for piano. No doubt. Only for piano.
Well, transcription for other instruments are possible, however they have no sense, so why should we bother about them? It's enough to try to imagine the tortures of a violinist or trumpeter who tries to play simultaneously and divergently two chromatic scales in the distance of a fourth – just only imagining causes incredible headache, handache, bodyache, brainache, so better not to try to play it... But you can do this on harpsichord, with no pain at all, and with no toil as well. So, the title could be written also in this way:

A CHROMATIC CONCERT[O] FOR PIANO and/or HARPSICHORD

We start from the bottom. From the very first key. It means from A. I don't know if A is the very first sound in the case of every grand-piano. With no doubt it is the very first key in the Liberland piano, big, black and shiny like a non-Liberland grand-piano. The fact the keyboard starts with A does not make this sound privileged in any way. The chromatic scale is unique just because no sound in it is privileged. Each sound can be the beginning and the end and the centre and any other place between the beginning, end and centre. If the sounds are not privileged, than the distances between them are not privileged either – there no better or worse intervals, though there are relations more or less closer, because aliquots live their own life and obeying their rules let them live so – we can chose from the chromatic scale any sounds we like or don't like and combine them in any sequences we like or don't like in this or that very moment. We start with a unison, but this does not mean unison is far more special than any other interval although it could deserve special treating since no other interval makes the left hand play exactly the same what the right hand plays. The unison can be called a perfect interval, an ideal we should chase, but we would never reach.
It could seem that playing chromatic scales in the distance of unison is absolutely easy – it's simply enough to play one scale with one hand only, left or right. Oh no! That's exactly not the point. It wouldn't be even cheating, it would be simply SOMETHING ELSE. To play two chromatic scales with two hands and make them sound AS IF one hand played one scale – this is something absolutely different than to play one scale with one hand (we must be aware that one hand will never play one chromatic scale and make it sound AS IF TWO HANDS PLAYED PARALLEL TWO SCALES). Two chromatic scales, one overlapping another, will never cover themselves ideally, two fingers will never hit the same key in exactly same manner as it is hit by one finger only, and just in these minimal differences and shifts, felt only by the fingertips, there is the essence and perfection of execution... And up to the highest, most extreme A. And then return. And once more. Maybe faster, maybe slower, a little bit slower. Maybe breaking tempo in the middle. Or stopping for a moment. Or stumbling. Going back a few keys. Accelerating and slowing down.... And once again. Down to the very bottom of the keyboard. To the lowest A.
Now in the distance of a second. Oh! This is extremely difficult! Because a finger of the right hand must run away fast enough to let the key overcome its inertia, to let the string vibrate, the sound burst and go out, and at once re-explode this time revived by a finger of the left hand. These fingers can not bump against each other, they can not, even for the shortest while, be together on the key. The left finger touches the key when the right finger has left it, and between leaving the key and touching it there must be enough time (and energy), to get it silent and then sound anew. It's extremely difficult. It's unfeasible.
And then a third. What a relief.
And a fourth. A fifth. A sixth. A seventh. And finally an octave. Of course everything convergently and divergently. Parallel – yes! first of all parallel. Legato and staccato. Rubato as well. Jumping and zigzagging. The left hand playing crotchets while the right hand playing quavers, or vice versa. Or sixteenth notes and thirty-second notes. With no doubt in various rhythms and meters. Triplets and quintuplets. And additionally using all possible dynamic subtleties: walking, galloping, jogging, dancing, hardly touching, caressing, trotting, treading, trampling, marching in heavy army shoes, stepping lazily like a cat...
Don't think an octave makes the case closed. There is a ninth, a tenth, an eleventh, a twelfth, and so on. And in each case we use all variants and variations described above and below. In front of us – seven octaves. Before us – seven octaves. A huge amount of sounds which is but a small part of extremely huge number.
Let's begin to reduce it.
Let's begin to subtract.
Before we begin to subtract sounds, we will play them all, however not in a natural sequence, but randomly. In a random sequence. Both hands will play the same sequence. Any sequence that comes to our mind in this or that very moment. Let it not repeat. Let it be different in each octave.... Now the left hand is going to play different sounds than the right hand. Let both hands play different sounds in different sequences, and let it not happen they play the same sounds, neither in unison, nor in one, two, three, nor even in seven octaves.....
Good. Let it whirl and melt. Let it be chaos. Let it be tossing and turning.....
Enough. Now we are going to subtract. To reduce.
At first one sound. A small hole in the tight curtain. A narrow crack in the clouds which covered the sky from horizon to horizon. A leaf suddenly turned up by a gush of wind and letting a thin, shy beam of light through the thick tree crown.... A lack hardly noticeably, almost invisible, almost inaudible. Is it possible to feel, to hear, the difference between 999 and 1000 sounds? Probably somewhere there are ears which can do that – even if they are, they are not numerous, they are very few. Which sound will be lacking? Any. For example the one omitted accidentally. The one being a victim of a stumbling finger, this stumbling caused by tiredness , a moment of distraction, lack of concentration, too much bravado, a tempo not fully controlled.
And then two sounds. Three. Four. And so on. Everything in various combinations. In all possible combinations and variations. If in the first passage we omitted the fifth sound, then in the second passage we will omit the fourth sound, and in the third passage – the eleventh one... If in the first passage we didn't play the second and the sixth sounds, then in the second passage we will not play the seventh and the eighth sounds..... In the beginning the left hand will omit the same sounds as the right hand, then not the same ones – after some time this process will give us a very interesting combination, though this combination will not be more interesting than any other combination, when the left hand will be playing exactly the same sounds, which the right hand will not be playing, and if the hands will be playing alternately, then our ears will hear full chromatic scale, and if the hands will not be playing alternately, then our ears will hear a set of double sounds, a kind of bisected chromatic scale...
Such a chaotic subtraction, such a barbarian elimination of the sounds respecting absolutely no relations, kinships and connections between them, would sooner or later resulted in sequences based just on those relations, kinships and connections, though they would be distinguished in no way among the others...... Thus, in this chromatic frenzy we could play sequences of half-tones and tones starting from the rock solid A. And vice versa: sequences of tones and half-tones..... Then major and minor scales. Then a set of all possible pentatonic scales. Then arpeggio triads in various inversions..... And finally we would arrive to the end. To our A. The first and the last one.
Thus the silence will emerge.
The night will fall.
The day will rise.
The universe will end to contract.
The world will be swallow by the black hole of the grand piano.
It is standing. It is gleaming. Swelled with sounds. Ready to explode in any moment. It's enough just to touch it, to caress it, and it will begin to hurl, to cry at once.
A.
Really?
It's high time for A-flat.
So we are adding A-flat.
Or everything what has been written above, but in the opposite order. And when we reach the full chromatic scale, then the space will be filled entirely, when we reach extreme distances, then we will begin to subtract, to reduce.
What will follow A-flat?
H.

Is there anybody that keep listening to us?

Is there anybody left in the hall?

Has anybody been in the hall?

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