Working Ensemble

Co-authored-by: <Marc-Andre Weibezahn> contact@maweibezahn.com

Author: aure

Sources/CSoundpipeAudioKit/Effects/EnsembleDSP.mm

@@ -23,6 +23,7 @@
     EnsembleParameterPan7,
     EnsembleParameterPan8,
     EnsembleParameterPan9,
+    EnsembleParameterNumberOfVoices,
     EnsembleParameterDryWetMix
 };
 
@@ -37,6 +38,7 @@
 
     ParameterRamper shiftRamps[9];
     ParameterRamper panRamps[9];
+    ParameterRamper numberOfVoicesRamp;
     ParameterRamper dryWetMixRamp;
 
 public:
@@ -59,6 +61,7 @@
         parameters[EnsembleParameterPan7] = &panRamps[6];
         parameters[EnsembleParameterPan8] = &panRamps[7];
         parameters[EnsembleParameterPan9] = &panRamps[8];
+        parameters[EnsembleParameterNumberOfVoices] = &numberOfVoicesRamp;
         parameters[EnsembleParameterDryWetMix] = &dryWetMixRamp;
     }
 
@@ -112,15 +115,19 @@ void reset() override {
     void process(FrameRange range) override {
         for (int i : range) {
             float dryWetMix = dryWetMixRamp.getAndStep();
+            int numVoices = (int)numberOfVoicesRamp.getAndStep();
+            
+            // Clamp number of voices between 1 and 9
+            numVoices = std::max(1, std::min(9, numVoices));
 
             float leftIn = inputSample(0, i);
             float rightIn = inputSample(1, i);
 
             float leftSum = 0.0f;
             float rightSum = 0.0f;
 
-            // Process through all 9 pitch shifters
-            for (int voice = 0; voice < 9; voice++) {
+            // Process through the specified number of pitch shifters
+            for (int voice = 0; voice < numVoices; voice++) {
                 float shift = shiftRamps[voice].getAndStep();
                 float pan = panRamps[voice].getAndStep();
 
@@ -139,9 +146,9 @@ void process(FrameRange range) override {
                 float pannedLeft, pannedRight;
                 sp_panst_compute(sp, panst[voice], &leftOut, &rightOut, &pannedLeft, &pannedRight);
 
-                // Add to sum with appropriate gain (divide by 9 to prevent clipping)
-                leftSum += pannedLeft / 9.0f;
-                rightSum += pannedRight / 9.0f;
+                // Add to sum with appropriate gain (divide by numVoices to prevent clipping)
+                leftSum += pannedLeft / numVoices;
+                rightSum += pannedRight / numVoices;
             }
 
             // Apply dry/wet mix
@@ -170,4 +177,5 @@ void process(FrameRange range) override {
 AK_REGISTER_PARAMETER(EnsembleParameterPan7)
 AK_REGISTER_PARAMETER(EnsembleParameterPan8)
 AK_REGISTER_PARAMETER(EnsembleParameterPan9)
+AK_REGISTER_PARAMETER(EnsembleParameterNumberOfVoices)
 AK_REGISTER_PARAMETER(EnsembleParameterDryWetMix)

Sources/SoundpipeAudioKit/Effects/Ensemble.swift

@@ -252,6 +252,19 @@ public class Ensemble: Node {
     /// Pan position 9 (-1 = left, 0 = center, 1 = right)
     @Parameter(pan9Def) public var pan9: AUValue
 
+    /// Specification details for numberOfVoices
+    public static let numberOfVoicesDef = NodeParameterDef(
+        identifier: "numberOfVoices",
+        name: "Number of Voices",
+        address: akGetParameterAddress("EnsembleParameterNumberOfVoices"),
+        defaultValue: 1,
+        range: 1.0 ... 9.0,
+        unit: .generic
+    )
+
+    /// Number of voices to use (1-9)
+    @Parameter(numberOfVoicesDef) public var numberOfVoices: AUValue
+
     /// Specification details for dryWetMix
     public static let dryWetMixDef = NodeParameterDef(
         identifier: "dryWetMix",
@@ -307,6 +320,9 @@ public class Ensemble: Node {
         self.pan8 = pans.count > 7 ? pans[7] : Self.pan8Def.defaultValue
         self.pan9 = pans.count > 8 ? pans[8] : Self.pan9Def.defaultValue
 
+        // Set number of voices based on the shifts array length, clamped to 1-9
+        self.numberOfVoices = AUValue(max(1, min(9, shifts.count)))
+        
         self.dryWetMix = dryWetMix
     }
 }

Tests/SoundpipeAudioKitTests/Effects Tests/EnsembleTests.swift

@@ -8,16 +8,18 @@ class EnsembleTests: XCTestCase {
 
     func testMajorChord() {
         let engine = AudioEngine()
-        let input = Oscillator()
+        let url = Bundle.module.url(forResource: "12345", withExtension: "wav", subdirectory: "TestResources")!
+        let input = AudioPlayer(url: url)!
         // Create a C major chord: C, E, G (0, 4, 7 semitones)
         let ensemble = Ensemble(input,
-                                shifts:[0, 7],
+                                shifts:[0, 4, 7], pans: [-1, 1],
                                 dryWetMix: 1.0)
-        ensemble.$shift2.ramp(to: 7, duration: 10.0)
+        ensemble.$shift2.ramp(to: 12, duration: 5.0)
+        ensemble.$pan2.ramp(to: -1, duration: 5.0)
         engine.output = ensemble
-        input.start()
-        let audio = engine.startTest(totalDuration: 10.0)
-        audio.append(engine.render(duration: 10.0))
+        let audio = engine.startTest(totalDuration: 5.0)
+        input.play()
+        audio.append(engine.render(duration: 5.0))
         audio.audition()
     }
 }

Tests/SoundpipeAudioKitTests/Effects Tests/PitchShifterTests.swift

@@ -5,19 +5,15 @@ import SoundpipeAudioKit
 import XCTest
 
 class PitchShifterTests: XCTestCase {
-    func testResetPitchShifter() {
+    func testPitchShifter() {
         let engine = AudioEngine()
-        let input = Oscillator(waveform: Table([1, 1]))
+        let input = Oscillator()
         let shifter = PitchShifter(input)
-        engine.output = shifter
+        shifter.shift = 7
+        engine.output = Mixer(input, shifter)
         input.start()
-        let audio = engine.startTest(totalDuration: 2.0)
+        let audio = engine.startTest(totalDuration: 1.0)
         audio.append(engine.render(duration: 1.0))
-        XCTAssertEqual(audio.toFloatChannelData()?[0].count, 44100)
-
-        shifter.reset()
-        audio.append(engine.render(duration: 1.0))
-
-        XCTAssertEqual(audio.toFloatChannelData()?[0].count, 88200)
+        audio.audition()
     }
 }