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diff --git a/src/main/java/com/jsyn/unitgen/Pan.java b/src/main/java/com/jsyn/unitgen/Pan.java
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+/*
+ * Copyright 1997 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.ports.UnitInputPort;
+import com.jsyn.ports.UnitOutputPort;
+
+/**
+ * Pan unit. The profile is constant amplitude and not constant energy.
+ * <P>
+ * Takes an input and pans it between two outputs based on value of pan. When pan is -1, output[0]
+ * is input, and output[1] is zero. When pan is 0, output[0] and output[1] are both input/2. When
+ * pan is +1, output[0] is zero, and output[1] is input.
+ * <P>
+ *
+ * @author (C) 1997 Phil Burk, SoftSynth.com
+ * @see Select
+ */
+public class Pan extends UnitGenerator {
+    public UnitInputPort input;
+    /**
+     * Pan control varies from -1.0 for full left to +1.0 for full right. Set to 0.0 for center.
+     */
+    public UnitInputPort pan;
+    public UnitOutputPort output;
+
+    public Pan() {
+        addPort(input = new UnitInputPort("Input"));
+        addPort(pan = new UnitInputPort("Pan"));
+        addPort(output = new UnitOutputPort(2, "Output"));
+    }
+
+    @Override
+    public void generate(int start, int limit) {
+        double[] inputs = input.getValues();
+        double[] panPtr = pan.getValues();
+        double[] outputs_0 = output.getValues(0);
+        double[] outputs_1 = output.getValues(1);
+
+        for (int i = start; i < limit; i++) {
+            double gainB = (panPtr[i] * 0.5) + 0.5; /*
+                                                     * Scale and offset to 0.0 to 1.0
+                                                     */
+            double gainA = 1.0 - gainB;
+            double inVal = inputs[i];
+            outputs_0[i] = inVal * gainA;
+            outputs_1[i] = inVal * gainB;
+        }
+    }
+}