Values 64-127 in unsigned translate to signed 0-+63

(1= -63, 64=0, 127= +63). 0 is undefined (out of range) per the +/-63 feedback level docs for range of values.

I'll have to get to the keyboard to give more practical information.

I would probably start with programming the feedback level to 127 (+63) and setup the "curve" (ramp) as unipolar and negative ratio adjusting the magnitude such that the level did not subtract more than 63 from the programmed value when superknob is full CW.

You're following roughly the same sort of thinking I had.

I tried that, and other permeations of that nature of relationships. Couldn't understand why it wasn't giving me the right result.

Also (somewhat related) couldn't find a curve that's able to have a different value in the negative on the left vs positive on the right (or vice versa).

It seems to be either: 0 to a value +/- or -n and +n or +n and -n

It doesn't, for example, seem to be possible to have a curve that goes from (for example) -10 on the left to +63.

So, in some cases, it's probably required to use a Part Assignable Knob driven by a Performance Assignable Knob that's then driven by the SuperKnob, in order to get asymmetric values. Dog Leg does have asymmetry, but also an unwanted dog leg.

argh, it's magic numbers.

If Assignable Knob is set to 127, and the Effect Level to 63 (both maximum) and then the Ratio set to -16, then the inversion works correctly: +63 to 0 as SuperKnob sweeps from 0 to Max.

If the desire is +63 to -63, then the Ratio needs to be -32

I asked a similar question when I first got the MODX.

What I learned is that the Assignables are not changing Parameter Values, they are "offsetting" or "biasing" parameter values.

I also learned that, rather than using a calculator to work out explicit values (ratio setting)... just use your ears, assuming you know what the desired aural effect is.

Take Delay as an example. A trick I learned going between two "extremes" is that as you turn Delay Level/Mix Up, you shoulf simultaneously turn Number of Repeats (Feedback) down... or you end up with a delay soup.

In this case you need to know how each desired setting sounds

Setting A = 1 Strong Repeat (low feedback, high Mix)
Setting B = 8-9 Repeats, Low "ambient" Mix.

Intention is to put Setting A with Assign Knob at Minimum, Setting B with Assign Knob at Maximum.

First, set actual Delay Parameters (e.g. Insert Effects InsA Edit) for Setting A.

Next make 2 Assigns on same knob
Assign 1 = Mix, will be unipolar negative slope (subtracting offset).
Assign 2 = Feedback will be Unipolar positive slop (adding offset).

Turn Assign Knob to Max.

In the Assign control parameter Edit screens, alter Ratio for each of Assign 1 and 2 **by ear** until you get the desired sound for Delay Setting B (low mix, high feedback).

I have found on nearly all musical equipment I own, you can rarely predict an absolute "value" setting that will provide the sound you want. I always go through a process of "Dialling In", i.e. twisting the knobs, paying no attention to their position, only listening for the point they sound correct.

BTW. In the DataList you will find tables with "non-named" Parameter Numbers. These are look-up tables. So instead of Assigning "Named" parameter "InsA FBK" you might want to control a non-specified parameter like "High Damp". You will see available Assign Targets like "InsA Parm6", Parm7 etc.

You would need to look up the Effect Table in the Datalist, and see which Parameter Number is assigned to "High Damp". It may or may not work. You need to check the hard button [Control Assign] with target parameter selected on screen. If the button lights, it will work, if it doesn't light, it won't work.

Don't be dismayed though. Using the above example, High Damp may be assignable in some Delay Models, while not in others. So its worth checking out other models if you really want to work with that parameter.

You will see a Model "*Control* Delay". This typically means you have good assignable options for those models.

AGREED!

I've previously described the Assignable Knobs and Motion Sequencers and their relationships with values as "Multipliers" or "Scalars" as that's what they're doing in programmery jargon, and this not being displayed more evidently has caused me to complain in various ways.

But it's this insight into the maths that was off, by a couple of factors, which is why I had a working formula for what I wanted, from which I was trying to narrow down what was right, but wasn't close. I'd been presuming that extremities would be mapped at 1:1.

What shocked me, caught me off guard, was that the ratio required was nowhere near 1:1, it's 1:4, or 1:8, depending on how you calculate it around a floating point or unsigned ints.

And it's because I was checking with my ear, that I was hearing it oscillate through and well past the extremity I wanted, it just didn't initially occur to me that the ratio would be so highly geared.

All of the modulation ("output" of curves) is addition. The degree for various shapes can be determined by fixing the input using superknob (which you can read the value 0-127) then modulate a value that's easier to determine what specific values result in specific outcomes. I typically use pitch for this.

My opinion has always been it would most helpful to be able to display the offset values so you could twist knobs to extremes (or specific locations) and watch the destination parameter reach the values. There would be lots of upside to this kind of option. Of course the ability to turn this display mode off so you could check the programmed value.

Outside of that - there's a bit of trial and error if specific values are what you're after.

What makes you think it's summing?

I haven't back-of-napkin calculated it, but I'm almost certain ratios to Assignable Knobs and the SuperKnob are multipliers.

Could be wrong. I wasn't even close to getting this right until I realised the ratios were way higher geared than I thought.

Ignoring motion sequence lanes (where the shapes are called "Pulses" ) - we have the "Mod/Control" -> "Control Assign" menu where the "curves" relate inputs to outputs. This is what I'm talking about here - so the relationship of superknob to assignable knobs is not the relationship I was describing. The input to this curve can be the Part-level Assignable Knob which itself will be 0-127 or any other "controller" which will range from 0-127. This input to the curve determines where you are on the X-axis (left and right). The input value of 0 places you on the far left side of this "curve" and the input value of 127 places you on the far right side of this "curve". The height of the "curve" at the given input (X position) determines the output value of the curve. Above the X axis are positive (adder) output values and below the X axis are negative (subtracting) output values.

Mapping the relationship of superknob to the assignable knobs (if that's what you're after) is easy to map out since superknob's position is advertised and assignable knob values are advertised as well. Superknob always goes from 0-127 and assignable knobs range from low to high evenly distributed. This particular behavior hasn't been that interesting to me because it's fairly self-evident what the relationship is.

(if linked) Assignable_Knob_Common_Value = (Superknob current value 0-127)/127 * (Assignable_Knob_Common_High-Assignable_Knob_Common_Low)+Assignable_Knob_Common_Low
Above assumes High>Low. If High<Low then the math would setup an inverse relationship with a different equation - but you get the general point. It's not too exciting for that level of the relationships.

"High" and "Low" tell you everything you need to know for the assignable knob common level. Then common to part level is a 1:1 relationship. Then the part level assignable knob is the direct input to the curve. And output follows the description in the 1st paragraph.

Using user curves can help you have control over output values at given input values. This way you can see how this part of the system (the curve output) is an adder.

At any rate - you can see how output of "curves" (defined as the shapes in "Mod/Control" -> "Control Assign" menus) would not ever describe any relationship between superknob and assignable knobs. Those relationships precede the curve translation (input to output) step.

I should have highlighted the most important word, as the context is presumed and implicit, but not explicit:

"but I'm almost certain ratios to Assignable Knobs and the SuperKnob are multipliers"

In other words, the thing that's changed by the Assignable Knobs, that thing is being impacted by multiplication, I think, at the rate of 0 to 127 multiplied by a portion of the ratio. Yes?

I think the Ratio is a Multiplier/Divider but its not directly multiplying parameter values. I wouldn't bother trying to calculate the formula of Ratio Number to Offset Value. There will be a formula, but I don't think there is any way of knowing what the actual "Offset" value is, because you can't see the Parameter value change in sympathy.

One way to look at it is like Cycle Derailleur Gears.

You have a Big Crank Cog (Assign Knob) and a bunch of smaller Gearing Cogs on the axle of the wheel (Gear Ratio) and a Big Rear Spoked Wheel (Offset)

When the Smallest Rear Gear Cog is selected (High Ratio), small turns of the Crank Cog result in big turns of the Rear wheel. ( High Sensitivity, Low Resolution, Low Torque).
When the Largest Rear Gear Cog is selected (Low Ratio), large turns of the Crank Cog result in small turns of the Rear wheel. (Low Sensitivity, High Resolution, High Torque).

With Ratio Value LOW, Big turns of the Assign Knob result in only small changes to Offset Value. Potential Max Offset values (+/-127 Unipolar or +/- 63 Bipolar) will never be reached with a full (300°) knob turn from minimum (full counter clockwise)

With a High or Max Ratio, the resulting Offset will be closer to its Max value with the Assign Knob turned to Max. At Max Ratio, a fully turned Assigned Knob will achieve Max Offset value.

The resultant Offset value is added (or subtracted) to the Parameter value. If the resulting Offset value, when added/subtracted to the parameter causes the Parameter Value to go beyond its Max or Min Value, the Parameter Value will assume only its Max 127 (or Min 0) value.

This of course depends on what the Parameter Value was to begin with (as set by you in the Edit Menus).

So the resultant Offset value is Proportional to the amount the Assign Knob is turned (it rotates approximately 300°... that is a 10% increment per 30° of turn, or clock position).

The "Proportion" is dependent on the Ratio Value.

What confused me initially was seeing the Assign Knob Value (0 through 127 or -64 through +64) and thinking that was the Offset value. It isn't, it is just the rotational position of the Assign Knob.

The last thing to get your head around is that the Ratio Value effectively controls the "Sensitivity" and therefore "Resolution" of the Assign Knob. Hypothetical example:- If you set the Ratio to Max (High) then you can achieve a full 0 to 127 Offset "swing" in just the first 30° of rotation. This turns the Assign Knob into little more than an ON/OFF switch. If you were aiming to "dial in" some specific Offset Value (lets say 73), then a High Ratio will cause you problems, because "73" lies somewhere between 0° and 30°... i.e. it is very low resolution.

Better to set a Low Ratio, such that the full 300° rotation of the Assign Knob "sweeps" through only a small and specific Offset Range that contains only target values you are interested in. In this case the Assign Knob behaves more like a "Fine Tuning Knob" than a "Coarse Tuning Knob".

This is worth noting for when you need to assign more than 1 parameter to an Assign Knob. There may be cases (and likely will be) where each Target Parameter requires a different resolution of adjustment.

Take an example. You want to use an Assign knob to alter both Filter Resonance and Cutoff in the same motion.

You want to vary the Resonance Parameter only slightly.
You want an audible Cutoff sweep for effect, the Cutoff Parameter needs to be varied more (in absolute value) than the Resonance.
In neither case do you want a "Full Sweep" of the Parameter Range.

For the Resonance, you want a Low Sensitivity, High Resolution Variance
For the Cutoff you want a Medium Sensitivity, Medium Resolution Variance.

You achieve this by setting a Low Ratio for Resonance, and Moderate Ratio for Cutoff.
Where these two Parameter values interact during the sweep, you adjust by setting the "Curve". The default is Linear, but you can set varying degrees of either Exponential (Concave) vs Logarithmic (Convex).

Having a Maths Degree helps, but you can get there through basic trial and error ("suck it and see") ) experimentation.

"but I'm almost certain ratios to Assignable Knobs and the SuperKnob are multipliers"

(if linked) Assignable_Knob_Common_Value = (Superknob current value 0-127)/127 * (Assignable_Knob_Common_High-Assignable_Knob_Common_Low)+Assignable_Knob_Common_Low
Above assumes High>Low. If High<Low then the math would setup an inverse relationship with a different equation - but you get the general point. It's not too exciting for that level of the relationships.

The relationship of superknob to the common assignable knobs is above.

The chain is:

Superknob ---(relationship quoted above)--->Common Assignable Knob #n---(1:1, value of Common == value of Part assignable knob)--->Part Assignable Knob #m

The Part Assignable Knob #m then is the input to a Part-defined curve with output to the destination parameter.