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diff --git a/src/main/java/com/jsyn/unitgen/PulseOscillatorBL.java b/src/main/java/com/jsyn/unitgen/PulseOscillatorBL.java
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+++ b/src/main/java/com/jsyn/unitgen/PulseOscillatorBL.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;
+
+import com.jsyn.engine.MultiTable;
+import com.jsyn.ports.UnitInputPort;
+
+/**
+ * Pulse oscillator that uses two band limited sawtooth waveforms.
+ *
+ * @author Phil Burk (C) 2009 Mobileer Inc
+ */
+public class PulseOscillatorBL extends SawtoothOscillatorBL {
+    /** Controls the duty cycle of the pulse waveform.
+     * The width varies from -1.0 to +1.0.
+     * When width is zero the output is a square wave.
+     */
+    public UnitInputPort width;
+
+    public PulseOscillatorBL() {
+        addPort(width = new UnitInputPort("Width"));
+    }
+
+    @Override
+    protected double generateBL(MultiTable multiTable, double currentPhase,
+            double positivePhaseIncrement, double flevel, int i) {
+        double[] widths = width.getValues();
+        double width = widths[i];
+        width = (width > 0.999) ? 0.999 : ((width < -0.999) ? -0.999 : width);
+
+        double val1 = multiTable.calculateSawtooth(currentPhase, positivePhaseIncrement, flevel);
+
+        // Generate second sawtooth so we can add them together.
+        double phase2 = currentPhase + 1.0 - width; // 180 degrees out of phase
+        if (phase2 >= 1.0) {
+            phase2 -= 2.0;
+        }
+        double val2 = multiTable.calculateSawtooth(phase2, positivePhaseIncrement, flevel);
+
+        /*
+         * Need to adjust amplitude based on positive phaseInc and width. little less than half at
+         * Nyquist/2.0!
+         */
+        double scale = 1.0 - positivePhaseIncrement;
+        return scale * (val1 - val2 - width);
+    }
+}