[sdiy] Silly vector synth question

[Gabriel Lindeborg]

So this statement, from the owner´s manual, is false?
"One oscillator can have 100% of the mix."

//Gabbe

Richard Wentk skrev 2011-02-08 00:00:
> Component 1 *is* a circle on the hardware.
>
> I may be getting confused if people are assuming that the diamond/square are the outer limits of the movement.
>
> They aren't. The path around the edge of the mixer is the in-circle of the diamond, so it's not physically possible to reach 0-100% in both axes all the way around the path.
>
> See e.g. here:
>
> http://biopixmod.com/images/93sshot_1_153f4b8.jpg
>
> So for example if I use Tom's equation when the pointer is at A, I *should* get 1:0:0:0.
>
> But in fact the joystick is offset inwards from A because it's on the edge of the circle and it can't be moved to A - so I still get a mix of the other oscillators.
>
> R
>
> On 7 Feb 2011, at 05:22, Tristan wrote:
>
>> I like this idea!
>>
>> But if component 1 was represented as a circle rather than a square then you could have an
>> arbitary number of different sources, uniformly or non uniformly distributed, around the circle.
>> Moving the stick around the edge of the circle would give a crossfade between each successive pair
>> of sources. This would be like wavetable/wave sequencing.
>>
>> Component 2 would be the sum of each of the sources divided by total number of sources. So
>> moving the stick closer to the centre of the circle would crossfade from the wave mix at that angle
>> on the circle to the sum of all sources, as for vector synthesis. You could also add quirks by adding
>> additional sources to component 2 that are not present on the circle or removing sources present
>> on the circle. Changes in the number of sources in component 2 would require adjusting the divisor
>> accordingly.
>>
>> So for one source on the circle the vector movement would have no effect. For two sources
>> distributed at 180 degrees on the circle you would get a linear crossfade. But for 3 or more sources
>> you would have many interesting vector synthesis possibilities.
>>
>> /Tristan
>>
>> On Mon, Feb 7th, 2011 at 3:26 PM, Richard Wentk<richard at wentk.com>  wrote:
>>
>>> I'd guess it works like this:
>>>
>>> Component 1 is a simple four axis volume control, with zero in the middle.
>>> Pushing the stick N scales the N output from 0 to 1, but with no S.
>>> Pushing it S scales from 0 to 1, but with no N. E+W work similarly.
>>>
>>> Component 1 gives you the correct mix around the edges, but creates a zone
>>> of silence towards the middle.
>>>
>>> Component 2 is a static 0.25*(N+S+E+W) mix of all four components that
>>> fills in the zone of silence.
>>>
>>> The relative mix of 1+2 is scaled by the *radius* from the centre
>>> position. So when the radius is 0, you get component 2 only, with the
>>> correct centre mix. When radius is 1, you get the edge mix from component
>>> 1.
>>>
>>> For all other radius values, you get a correct proportional mix of all
>>> four components.
>>>
>>> Doing the rect to pol conversion is slightly more work, but you only need
>>> to do it for each control change.
>>>
>>> I'm not sure linear scaling covers this. At - say - NE, you should get
>>> 50:50:0:0. If you use linear scaling, you get some element of W+S mixed
>>> in, because the x&  y distances from W+S aren't 100%.
>>>
>>> R
>>>
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