From 3496fa99255d6b6ac409fd68535a7abf10ac21cf Mon Sep 17 00:00:00 2001
From: Stephane Letz <letz@grame.fr>
Date: Fri, 13 Nov 2020 22:57:24 +0100
Subject: [PATCH] Correct DSP examples (voltage range). Improve documentation.

---
 Faust.md                   | 8 +++++---
 examples/organ.dsp         | 4 ++--
 examples/physicalmodel.dsp | 2 +-
 examples/synth.dsp         | 2 +-
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/Faust.md b/Faust.md
index 2157475..31e03bd 100644
--- a/Faust.md
+++ b/Faust.md
@@ -25,11 +25,11 @@ So a button or checkbox UI item can use the `[switch:N]` metadata to be associat
 Other metadata:
 - `[scale:lin|log|exp]` metadata is implemented.
 
-The [rack.lib](https://github.com/VCVRack/VCV-Prototype/blob/faust/res/faust/rack.lib) Faust library contains usefull functions to convert VC signals, and can be enriched if needed. 
+The [rack.lib](https://github.com/VCVRack/VCV-Prototype/blob/faust/res/faust/rack.lib) Faust library contains usefull functions to convert CV signals, and can be enriched if needed. 
 
 ## DSP examples
 
-Here is a simple example showing how oscillators can be controlled by UI items:
+Here is a simple example showing how oscillators can be controlled by GUI items, associated with metadata in the DSP code:
 
 ```
 import("stdfaust.lib");
@@ -40,9 +40,11 @@ gain = hslider("gain [knob:2]", 0.5, 0, 1, 0.01);
 gate = button("gate [switch:1]");
 
 // DSP processor
-process = os.osc(freq) * gain, os.sawtooth(freq) * gain * gate;
+process = os.osc(freq) * gain * 5, os.sawtooth(freq) * gain * gate * 5;
 ```
 
+Following the VCV Prototype model, note that audio outputs **are multipled by 5** to follow the [-5v..5v] range convention. 
+
 The standard examples ported to Faust can be seen in the examples folder:
 
 - [gain.dsp](https://github.com/VCVRack/VCV-Prototype/blob/faust/examples/gain.dsp)
diff --git a/examples/organ.dsp b/examples/organ.dsp
index 3763da0..acb2a88 100644
--- a/examples/organ.dsp
+++ b/examples/organ.dsp
@@ -18,7 +18,7 @@ Additive synth: 3 sine oscillators with adsr envelop.
 Use the 3 first VC inputs to control pitch, gate and velocity.
 */
 
-process(pitch, gate, vel) = voice(freq) * en.adsr(attack, decay, sustain, release, gate) * vel : *(vol) : panner(pan)
+process(pitch, gate, vel) = voice(freq) * en.adsr(attack, decay, sustain, release, gate) * vel : *(vol) : panner(pan) : *(5),*(5)
 with {
 	freq = cv_pitch2freq(pitch);	
-};
\ No newline at end of file
+};
diff --git a/examples/physicalmodel.dsp b/examples/physicalmodel.dsp
index 61cabf9..ee35e5b 100644
--- a/examples/physicalmodel.dsp
+++ b/examples/physicalmodel.dsp
@@ -43,4 +43,4 @@ with {
 		between 0 and 1 with 1 for the maximum amount of reverb.]", 0.3333, 0, 1, 0.025));
 };
 
-process = frenchBell_ui <: freeverb_demo;
+process = frenchBell_ui <: freeverb_demo : *(5),*(5);
diff --git a/examples/synth.dsp b/examples/synth.dsp
index edd3e30..a6a63ec 100644
--- a/examples/synth.dsp
+++ b/examples/synth.dsp
@@ -31,4 +31,4 @@ swl_red(i) = vbargraph("[switchlight_red:%i]", 0, 1);
 swl_green(i) = vbargraph("[switchlight_green:%i]", 0, 1);
 swl_blue(i) = vbargraph("[switchlight_blue:%i]", 0, 1);
 
-process = os.osc(freq1) * vol1, os.sawtooth(freq2) * vol2 * gate, os.square(freq2) * vol2 * check;
+process = os.osc(freq1) * vol1 * 5, os.sawtooth(freq2) * vol2 * gate * 5, os.square(freq2) * vol2 * check * 5;