[sdiy] Control Interfaces (was Wakeman)

[Ingo Debus]

Rainer Buchty wrote:
>>There are no yogi skills required to control more than a few
>>parameters while playing an instrument. Look for instance what violin
>>or wind instrument players do all the time.
> 
> 
> So where exactly do they use their feet? :)
> 
> The violin player usually controls two parameters with one hand (pitch and
> pitch bend), and another two with the bow (staccato/legato, "expression").
> 
> Similarly, the wind instrument player applies the basic note information
> with his hands, additional pitch control is provided through the blow
> pressure. In addition, "expression" can be added by the way the instrument
> is blown (volume, "modulation effects").

Ian Fritz already commented on the violin. I play flute, where also a 
lot of things can be varied while playing: breath pressure (or amount 
of air), mouth aperture, direction of airflow, tension of facial 
muscles, mouth cavity (not very much effect on a flute, but try a 
harmonica), the mysterious "breath support" thing (it does affect the 
tone, but perhaps just translates into breath pressure, I don't know) 
and probably more.

>>Or consider a vocoder: you can control a whole filter bank with your
>>mouth. You cannot control each filter gain individually, but you can
>>do a lot more than with two hands and a set of knobs.
> 
> 
> Yes, but here again we're at the point of a "correlated controller", just
> like the "brightness knob" I mentioned earlier.

Yes, but my point was, you cannot do this with only one knob. If this 
was possible, a vocoder could be made with only one analysis and one 
synthesis filter. When you form vowels with your mouth, several 
parameters are involved. The number of parameters is probably lower 
than the number of filter channels in the vocoder (so you can't 
control each filter independently), but certainly higher than one. 
Thus a vocoder (with microphone) is a multi-dimensional controller.

> So maybe the overall question is: what would a "keyboard" (for the lack of
> any better word...) would look like which allows you playing any kind of
> chords (-> polyphonic play) but gives you a similar amount of
> expression/modulation controls as e.g. string or wind instruments while
> still being playable at similar ease of the piano keyboard?

That's a tough one. Even the commercially available wind controllers 
(WX/EWI/EVI) which are monophonic allow only control of two 
"expression" parameters, breath pressure and lip pressure. They do 
have additional controllers like thumb wheels, and of course one can 
add foot pedals, but that's possible with a keyboard too.

Ingo