[sdiy] Make a CS80

[cheater cheater]

On Mon, Apr 5, 2010 at 12:50, Tom Wiltshire <tom at electricdruid.net> wrote:
>
> On 5 Apr 2010, at 11:00, cheater cheater wrote:
>
>> I think that it would be nice to have both a proximity/position sensor
>> (hall?) for reading how far the key is depressed, and a pressure
>> sensor at the end of the travel, followed by a final high-pressure
>> tactile switch that presses in when the pressure sensor is at the
>> maximum.. that could make for some interesting playing techniques
>>
>> For example you could control a pan flute sound, and the position
>> sensor could fade in more 'breath' as you're depressing the key. Once
>> the key touches the pressure sensor (which could have a metallic
>> terminal with a matching terminal on the key body to tell when the key
>> is there) the resonance could start happening and the pressure would
>> control the crossfade between the breathy sound (making it decay to
>> 30% at maximum pressure) and the resonance (making it raise to 100%).
>> Then the tactile switch would completely decay the breathy sound to 0,
>> via a 15ms release time.
>
> You've got some good ideas, but you don't half make things complicated.
> If you've got a pressure sensor already, what's the need for contacts to
> detect whether the key is touching it,

tactile feedback

> or a high-pressure switch at the
> maximum pressure.

more tactile feedback

> Both 'switches' can be implemented as thresholds on the
> output from the pressure sensor.

This won't be as repeatable on the electronic side because of
variations in the parts; but more importantly it won't be repeatable
on the human side - because a human can't really learn muscle memory
based on a threshold somewhere in 'mid air'. Ever tried to learn how
far up from the ground is exactly 1 meter?

> A zero reading is "key not touching",
> <5units is "key just touching", and >95units is "maximum pressure".
>
>> Or you could have a violin style sound where the string gets bowed
>> when you're depressing the key, then the pressure heightens the
>> vibrato, and the tact key plucks it and the sound is over; this could
>> be used by quick-handed players to have control between
>> bowing/staccato/pizzicato.
>>
>> This scheme doesn't even exclude the additional information of
>> velocity, but definitely gives it a new context, and it could be used
>> for something else yet to give even more expression to the sound..
>>
>> Had only MIDI not happened, we'd have hundreds of synths like that
>> since the 80s.
>
> And they'd all use some proprietary protocol and none of them would talk to
> any of the others - great!

Which would be just fine, because you can always make a converter :)

> I realise you have a deep-seated hatred of MIDI, and I agree it is getting a
> bit long in the tooth, but it did a great job. Standard wars are an absolute
> PITA for end-users

Who cares about end-users? :-)

And seriously, we're talking about pro equipment here. If a synth
could cost 10000 usd of today-money, then what difference did it
really make if you needed a converter that cost 800? None for someone
who looked at this as an investment.

> (How many different IR remote controls do you have in
> your lounge?! Why didn't *they* find a standard to work to?)

Or, you can have an universal remote, which existed since the 80s!

> MIDI meant that
> you could buy a keyboard from any manufacturer and be sure that it would
> talk to equipment made by *any* other manufacturer. It made the whole
> computer-music bedroom studio thing possible, and opened up a whole world of
> options. There are many things it doesn't do, and it is a bit
> keyboard-centric, but it was an incredible effort given the time it was
> done.

I have a better idea. Why limit ourselves to keyboard instruments? Why
don't we make all symphonic instruments work the same way? For example
let's invent this 'rubber pear' interface:

http://us.123rf.com/400wm/400/400/pumba1/pumba10801/pumba1080100014/2337714.jpg

it actuates the breath on a flute, trumpet, saxophone, and any other
breath instruments. It could also actuate mallets on xylophones or a
timpani via a cylinder balloon which blows up when you press on the
pear, and similarly it could move the bow of a violin.

> Anyway, speed was always MIDI's biggest weakness, and with MIDI-over-USB,
> that's becoming a moot point. It may yet live into the 21st century.

Thanks to modern polymers and micro-materials we can make the rubber
pear to exacting specifications and it will work extremely fast (the
notes will arrive as quickly as you can hit the different rubber
pears, really)

Sound like a good idea? No?...

;-)

MIDI really is that rubber pear, it robs the user of any possibility
expression; anyone who's ever played a real musical instrument knows
that velocity is just a tiny factor in the overall sound. And you know
what those rubber pears are good for... Yamaha can take that rubber
pear and stick it up their collective *utt :-P

D.