The "hybrid" synthesizer / sampler UVI Falcon allows its its presets ("programs" in Falcon terminology) to call scripts written in UVIScript, a domain-specific scripting language built on top of the Lua scripting language. So far, this repository contains just one script (the only one I have written), together with a Falcon program (preset) that demonstrates the script's use. In this README, I shall share some of what I have learned.
There are no examples in UVI-supplied sound banks of programs where macros on Falcon's standard Info Page control a DAHDSR's attack, decay, sustain and release. The problem is that Falcon does not provide a way to scale macro values (range 0 to 1) up to required parameter value maxima greater than one. The maxima for the DAHDSR's AttackTime, DecayTime and ReleaseTime parameters are 10, 30 and 20 seconds respectively. So UVI-supplied programs provide attack, decay, sustain and release knobs on image GUIs defined in scripts.
The DAHDSR Controller script controls a program-level DAHDSR's attack, decay, sustain and release parameters with macros defined in the standard GUI, avoiding the need for a script-defined image GUI. (Tip: To develop a script-defined image GUI instead, have a look at estevancarlos's tutorial.) Scripts\DAHDSR Controller.lua itself is just a stub that references the Scripts\DahdsrController\DahdsrController.lua script. The purpose of the stub is to prevent the whole script from becoming embedded in the Falcon program file.
This is the GUI of Tibetan Horns, the example Falcon program that contains the DAHDSR Controller script processor:
To allow the macros to control the DAHDSR's parameters, there are ADSR knobs, as intermediaries, on the script processor itself (shown on Falcon's Events page):
These script processor knobs need to be configured to be modulated by the corresponding macros, like this:
A limitation of this technique is that, in order to initialise the values of the Info Page macros and the script processor knobs to the corresponding DAHDSR parameter values, the internal macro Names in the program have to be hard-coded into the script. So DahdsrController.lua currently contains the Names of the ADSR macros in Tibetan Horns:
| DisplayName | Name |
|---|---|
| Attack | Macro 5 |
| Decay | Macro 6 |
| Sustain | Macro 7 |
| Release | Macro 8 |
To avoid having to hard-code the macro Names in the script, I have investigated accessing the macros via their DisplayNames, which are what are shown in the GUI. Unfortunately, that appears to be impossible. So, to find the program's internal macro Names, look in the Falcon program file (Programs\Tibetan Horns.uvip in the example) with a text editor. Tip: If you save the program file with an XML header in a smart editor, you will see the program's XML colour-coded. This works with Notepad++ (Windows), Visual Studio Code (Windows and Mac) and, I expect, BBEdit/TextWrangler (Mac). In Falcon program files, a macro is called a ConstantModulation. So look for something like this:
<?xml version="1.0" encoding="utf-8"?> <!-- You may add this XML header line. -->
<UVI4>
<!-- Many lines of XML code are ommitted here. -->
<ConstantModulation Name="Macro 5" Bypass="0" DisplayName="Attack" Bipolar="0" Style="0" Value="0">To change the the macro Names in the script, edit UVIScript file Scripts\DahdsrController\DahdsrController.lua. Tip: To see the Lua code in the script file colour-coded, use a smart editor. This works with Notepad++ (Windows), Visual Studio Code (Windows and Mac) and, I understand, BBEdit/TextWrangler (Mac). The macro Name constants to edit are immediately after the long introductory comment:
-- Constants
local AttackMacroName = "Macro 5"
local DahdsrName = "DAHDSR 1"
local DecayMacroName = "Macro 6"
local ReleaseMacroName = "Macro 8"
local SustainMacroName = "Macro 7"To make control of the DAHDSR's parameters by the macros more ergonomic, the script processor also has knobs to specify the maximum number of seconds that may be specified by the Attack, Decay and Release macros and knobs:
For example, anything up to the DAHDSR's ReleaseTime parameter maximum of 20 seconds may be specified as the maximum for the Release macro and knob. The Tibetan Horns example program does not provide macros corresponding to the three maximum seconds knobs. But those could easily be added.
The Tibetan Horns Falcon program is provided primarily as an example host for the DAHDSR Controller script processor. However, its other features may be of interest. I developed the DAHDSR Controller script as part of making my own versions of the programs in Falcon's Organic Pads sound bank. The Tibetan Horns example program cannot be played in Falcon unless the Organic Pads sound bank is installed.
Organic Pads programs have four timbre layers that can be mixed together: Synthesis, Sample, Noise and Texture. In the original programs, the layers are mixed by a single X-Y control on the script-defined GUI. That limits the possible mixing permutations. As my hardware MIDI controllers include five expression pedals, I have replaced the X-Y control with four macros. Each of these macros modulates the gain of a specific layer, and each macro is in turn modulated by the MIDI CC of an expression pedal. That way I can vary the gains of the four layers completely independently of each other.
The other change I've made to the sound of the program is that all delay and reverb effects have been bypassed.
Reducing the attack time to zero while playing intermittently causes low volume and then silence. But I have not found the problem to consistently occur with any specific program. When the problem happens, sometimes Falcon then becomes silent altogether, even when switching to a different program. If Falcon is then restarted, sound comes back.