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2nd movement of C.P.E. Bach sonata for flute + keyboard, Recorder pitch bending demo.
Second movement of C.P.E.Bach Sonata in C major for flute and obbligato keyboard.
Real Audio [Real player 5 - 32 K bps, 581 Kb].
Mp3 [128 kbit, 2,319 Kb]
Harpsichord is playback of midi clip adaptively tuned by John deLaubenfels.
Played on tenor recorder.
Adaptive tuning = micro-adjusting pitches of the notes so that the "same note" is played at varying pitches. Often the aim is to achieve as pure harmonies as possible - for most music involving harmonic progressions, the maths is such that no fixed pitch system can quite achieve the pure harmonies possible with adaptive retuning.
John deLaubenfels is the pioneering researcher, and main person working in this field at present. However basic idea of adaptive tuning goes back to the Middle ages, when composers experimented with keyboards with more than twelve notes to an octave, with the pitches varied by having split keys, or some such system.
So what is it like to play? First thing one notices are the very wide minor thirds, - on recorder, any cents deviation over 10 cents requires quite determined pitch bending! Sometimes I use finger shading to help.
Then, one notices many gentle fluctuations of pitch of the melody. It is wonderful the way these fit in with the flow of the tune, for instance, pitch tends to go up at the climax of a phrase if it is conclusive (including end of the movement) while down if it is leading into something else. Not sure why that is but it works very nicely.
Then when it really comes together, what one notices is the way all three parts work together harmonically, rather than each going its separate way somewhat. When you hear the harpsichord pitch changing to fit in with your tune, it almost feels like there is a live player there playing with you. As much of such a feeling as one gets from rhythmic responsiveness (of which there is none in this as I sequenced the original midi clip in NWC with a steady tempo of crotchet=79).
This is in John's version targetting 9/10 for the dom7th except when the fifth of the chord is missing when it targets the 8/9.
This is of course an amateur recording of the piece, but I hope my enthusiasm and evident enjoyment of playing with the adaptively tuned keyboard makes it worth listening to. It was perhaps originally written for amateurs to perform as it is very easy.
The baroque flute had a narrower range than the modern flute. Many pieces for flute up to just short of J.S. Bach, (and the Bach flute sonatas too, if you can manage the occasional rather high notes) are playable on recorder.
This movement has a high C# in it which is a tricky note on recorder - I use the fingering 0 1 Ø 3 4 Ø 6 7, which works on most recorders. It's in the first high phrase the recorder plays.
For pitch bending, I use finger shading, and also a technique involving varying the amount of turbulence in the air stream - a fairly subtle effect I suppose, but when you are talking about pitch bends of 10 cents, then it is very useful indeed. Range is about +- 25 cents at max possible bend, and more like +- 15 cents for comfortable pitch bending. Apparently, there is some controversy about whether the technique works at all! Well, I vouch for it that it does.
As for timbre, I think perhaps the recorder is a reasonable stand in for baroque flute, - if you can play it on modern flute, then why not on recorder?
It is a great pleasure to play the recorder with adaptively tuned harpsichord in this piece, and though quarter comma meantone is also nice (possibly original intention to judge by how nice it sounds), the adaptive tuning of these pieces is so incomparably much nicer to play with. You really can relax and enjoy the music as you play!
Here is a demo clip for the technique. All the notes are fingered normally, and the echo effects and pitch bending are done entirely using this turbulence technique. Recorder pitch bend demo recorder_improv.ra.
To try out the technique, first blow a narrow stream of air across the mouthpiece. Now try blowing normally, and in as gentle and steady a fashion as possible, and compare the two notes. You should find that when blowing across the mouthpiece, the note is sharper. This seems to be because of the amount of turbulence in it. My guess as to why this may happen, for what it's worth, is that small eddies are very stable, so they probably survive the passage, and when they hit the edge, perhaps this is what changes the pitch slightly. At anyrate, it works, whatever is actually happening.
Once one has heard the effect, one can then learn to do the same thing by playing in a more normal fashion, but changing the amount of turbulence by the "way one blows" - hard to describe, but one can get the hang of how to do it. Then one can bend the pitch wherever one wants to put it over a range of about +- 15 cents, with the range depending a bit on which note one plays.