Many thanks go to Davidson for his very handy range of SE modules.
This particular module allows us to have a visual representation of a filter’s frequency response, and to be able to control the cutoff and resonance from either the graphic display, or an external control voltage. I have used an SV filter in this project.
The DAM Filter Draw module.
Hint: The usual the text supplied to this plug will give you a pop up hint when the mouse is over the display window.
Menu Items/Selection: Used for the right click menu items and the choice made.
Mouse Down X:
Mouse Down Y:
Pos X Cut: Input/Output for the filter X value, which is connected to the filter’s Pitch or Frequency plug. Values are between 0-1 Floating, so when connecting to a Patch Memory always use the Animation Position plug.
Pos Y Reso: Input/Output for the filter Y value, which is connected to the filter’s Resonance, Q or Gain plug. Values are between 0-1 Floating, so when connecting to a Patch Memory always use the Animation Position plug.
Grasp Off/On: When this plug has the Boolean value of 1 (On, or True) you can adjust the parameters only by dragging the shape curve. When it has a Boolean value of 0 (Off, or False) you can adjust the Cut and Reso values by clicking or dragging anywhere in the display window.
Filter: You can set the filter mode for the display using the appropriate integer values; Low Pass=0,High Pass=1,Band Pass=2, Band Reject=3,Peak=4,Low Shelf=5,High Shelf=6,ST=7,CN=8
Note: ST allows you to drag the filter between Band Pass and Band Reject, CN gives a variable frequency, variable width Band Pass (I’m going to assume here that these options relate to a future filter release from Davidson?)
Slope: -12db (Single pole SV)=0, -24db/Octave (2 Pole SV)=1.
BG ARGB: Sets the background colour of the display window in the usual ARGB format. Hex codes won’t work here.
Line size: Sets the colour of the curve line in the usual ARGB format. Hex codes won’t work here.
Gradient Flip: You can invert the positions of the gradient colours using 0 or 1.
Fill Below/Above Center: Places the fill colours above or below the filter curve (although this is an integer plug there are only the two options). Below the curve = 0,
above the curve = 1.
Fill Top ARGB: Specify the upper portion of the gradient fill colour as ARGB (Not Hex, that won’t work)
Fill Bottom ARGB: Specify the upper portion of the gradient fill colour as ARGB (Not Hex, that won’t work)
Grid Off/On: 1 switches the centre grid on, 0 turns it off.
Grid Box Off/On: 1 switches the outer grid on, 0 turns it off.
Grid Line Size: Sets the thickness of the grid Note: this is a Floating point value not integer so you have a fine control over the grid thickness.
Grid ARGB: Specify the grid colour as ARGB (Not Hex, that won’t work)
Filter type options.
The Filter Draw module has more filter type options than we need but as the ones we are using are in the same sequence as the SV filter options this doesn’t matter. The unwanted options are just not used ( the drop down list is automatically taken from the SV filters options list).
Controlling the filter from the Filter Draw module.
This is done via the the two PatchMemory Float3 modules:
Pos X Cut controls the filter’s cutoff frequency
Pos Y Cut controls the filter’s resonance level.
These modules convert from GUI values to DSP, which is then converted from Float values to Voltage values for the Cutoff and Resonance plugs on the filter module, and convert the 0-1 Float range to the normal 0-10 V range for DSP controls.
CV Inputs.
Next we have two QTN_Volt2GUIFloat modules to take the external control voltages, and perform two functions 1) convert the incoming DSP voltage to GUI float, 2) redirect the output Float value to the left hand side of the module so it can be connected to the PatchMemory Value plug.
When this input voltage changes it will shift the appropriate x or y position on the Filter Draw module, and the related control value on the SV filter.
Filter Options.
As I said earlier we don’t need to set up any specially formatted lists, we can just use to PatchMemory List3 modules, and ED List Entry modules (OK you can use the stock ones, but I like Elena’s as you can set the background and text colours to suit your colour scheme).
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