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diff --git a/src/com/jsyn/unitgen/SineOscillator.java b/src/com/jsyn/unitgen/SineOscillator.java
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+/*
+ * Copyright 2009 Phil Burk, Mobileer Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.jsyn.unitgen;
+
+/**
+ * Sine oscillator generates a frequency controlled sine wave. It is implemented using a fast Taylor
+ * expansion.
+ * 
+ * @author Phil Burk (C) 2009 Mobileer Inc
+ */
+public class SineOscillator extends UnitOscillator {
+    public SineOscillator() {
+    }
+
+    public SineOscillator(double freq) {
+        frequency.set(freq);
+    }
+
+    public SineOscillator(double freq, double amp) {
+        frequency.set(freq);
+        amplitude.set(amp);
+    }
+
+    @Override
+    public void generate(int start, int limit) {
+        double[] frequencies = frequency.getValues();
+        double[] amplitudes = amplitude.getValues();
+        double[] outputs = output.getValues();
+        double currentPhase = phase.getValue();
+
+        for (int i = start; i < limit; i++) {
+            /* Generate sawtooth phasor to provide phase for sine generation. */
+            double phaseIncrement = convertFrequencyToPhaseIncrement(frequencies[i]);
+            currentPhase = incrementWrapPhase(currentPhase, phaseIncrement);
+            if (true) {
+                double value = fastSin(currentPhase);
+                outputs[i] = value * amplitudes[i];
+            } else {
+                // Slower but more accurate implementation.
+                outputs[i] = Math.sin(currentPhase * Math.PI) * amplitudes[i];
+            }
+        }
+
+        phase.setValue(currentPhase);
+    }
+
+    /**
+     * Calculate sine using Taylor expansion. Do not use values outside the range.
+     * 
+     * @param currentPhase in the range of -1.0 to +1.0 for one cycle
+     */
+    public static double fastSin(double currentPhase) {
+        // Factorial constants so code is easier to read.
+        final double IF3 = 1.0 / (2 * 3);
+        final double IF5 = IF3 / (4 * 5);
+        final double IF7 = IF5 / (6 * 7);
+        final double IF9 = IF7 / (8 * 9);
+        final double IF11 = IF9 / (10 * 11);
+
+        /* Wrap phase back into region where results are more accurate. */
+        double yp = (currentPhase > 0.5) ? 1.0 - currentPhase : ((currentPhase < (-0.5)) ? (-1.0)
+                - currentPhase : currentPhase);
+
+        double x = yp * Math.PI;
+        double x2 = (x * x);
+        /* Taylor expansion out to x**11/11! factored into multiply-adds */
+        double fastsin = x
+                * (x2 * (x2 * (x2 * (x2 * ((x2 * (-IF11)) + IF9) - IF7) + IF5) - IF3) + 1);
+        return fastsin;
+    }
+}