Re: [LAD] panning thoughts

On Mon, Nov 22, 2010 at 02:14:54PM +0100, Remon Sijrier wrote:

> On Sunday, November 14, 2010 01:01:17 am fons@email-addr-hidden wrote:

> > Let me guess: a combination of a badly designed widget that has no
> > central position, and a print format that doesn't show the smallest
> > step.
>
> Hmm, you never used Traverso I see ... at least not in the way it should be
> used: there are no widgets in Traverso to control gain/pan values.

I have a look at it every now and then to see how it's evolving. Last time
it still was limited to stereo, and it crashed within minutes. Which does
indeed mean I don't use it.
 
> But you are correct that the pan/gain 'indicators' have less precision then
> the actual gain/pan values.
>
> One of the reasons I didn't fix this earlier is due I've no idea how much
> precision is needed. I.e. how small a step value do we want/need for gain and
> pan, and do we actually want to show that in the indicator? E.g. a value of
> -3.05 dB is a bit overkill?

There's a simple rule: if the indicator says '-3.0' then the actual value
should be -3.0. Not -2.96 or -3.04. In other words the indicator should have
the required precision to be able to show *all* possible values exactly.
Steps of 0.1 dB for gain are perfectly OK, even bigger ones. You have
to 'smooth' the transition anyway if the gain changes.

> Right now gain increment steps are 0.05 dB for gain, and there are 200 steps
> for pan normalized between -1, 1

I hope '200 steps' means 201 positions. You need an odd number in order to
have a central position.
 
> Just some thoughts: rotary knob controls are better to control by the human
> then sliders are, probably due the movements of the fingers are much more
> precise?

Real ones provide support so the user can hold the knob without moving it even
in shaky conditions.

> The use of sliders vs knobs in software imho still is a different issue since
> you have to control those with a mouse, right?
> And this mouse movement dictates how good the movement (and precision of that
> movement) can be done in combination with how the knob/slider 'widget' is
> implemented. E.g. the width of the slider is 100 pixels, then you can't use
> more then 100 steps.

You can, and in fact the sliders I'm using in some new projects do have
sub-pixel accuracy, also visually.

> Traverso does away with that by using the relative mouse moving distance,
> allowing for mouse movements to be translated in relatively small gain/pan
> adjustements in effect giving the user a much better control over the
> gain/pan/other values.

Relative motion is the only one that makes sense for a slider. There's nothing
more useless than a control that jumps to the value you click on.

> Side effect is that the mouse can be moved physically
> for over long distances without being limited by screen sizes, so no matter if
> you're using a large or small screen, a large or small knob/slider, it always
> feels the same, with much more precision :)

Which in general is a good idea. OTOH, fader attenuation should 'go faster' for
low gain values (e.g. below -40 dB w.r.t. the maximum), so a fixed step is not
always optimal.

Ciao.

-- 
FA
There are three of them, and Alleline.
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