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diff --git a/src/com/jsyn/unitgen/RedNoise.java b/src/com/jsyn/unitgen/RedNoise.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.util.PseudoRandom;
+
+/**
+ * RedNoise unit. This unit interpolates straight line segments between pseudo-random numbers to
+ * produce "red" noise. It is a grittier alternative to the white generator WhiteNoise. It is also
+ * useful as a slowly changing random control generator for natural sounds. Frequency port controls
+ * the number of times per second that a new random number is chosen.
+ * 
+ * @author (C) 1997 Phil Burk, SoftSynth.com
+ * @see WhiteNoise
+ */
+public class RedNoise extends UnitOscillator {
+    private PseudoRandom randomNum;
+    protected double prevNoise, currNoise;
+
+    /* Define Unit Ports used by connect() and set(). */
+    public RedNoise() {
+        super();
+        randomNum = new PseudoRandom();
+    }
+
+    @Override
+    public void generate(int start, int limit) {
+        double[] amplitudes = amplitude.getValues();
+        double[] frequencies = frequency.getValues();
+        double[] outputs = output.getValues();
+        double currPhase = phase.getValue();
+        double phaseIncrement, currOutput;
+
+        double framePeriod = getFramePeriod();
+
+        for (int i = start; i < limit; i++) {
+            // compute phase
+            phaseIncrement = frequencies[i] * framePeriod;
+
+            // verify that phase is within minimums and is not negative
+            if (phaseIncrement < 0.0) {
+                phaseIncrement = 0.0 - phaseIncrement;
+            }
+            if (phaseIncrement > 1.0) {
+                phaseIncrement = 1.0;
+            }
+
+            currPhase += phaseIncrement;
+
+            // calculate new random whenever phase passes 1.0
+            if (currPhase > 1.0) {
+                prevNoise = currNoise;
+                currNoise = randomNum.nextRandomDouble();
+                // reset phase for interpolation
+                currPhase -= 1.0;
+            }
+
+            // interpolate current
+            currOutput = prevNoise + (currPhase * (currNoise - prevNoise));
+            outputs[i] = currOutput * amplitudes[i];
+        }
+
+        // store new phase
+        phase.setValue(currPhase);
+    }
+}