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diff --git a/src/com/jsyn/util/PseudoRandom.java b/src/com/jsyn/util/PseudoRandom.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.
+ */
+/**
+ * Sep 9, 2009
+ * com.jsyn.engine.units.SynthRandom.java 
+ */
+
+package com.jsyn.util;
+
+import java.util.Random;
+
+/**
+ * Pseudo-random numbers using predictable and fast linear-congruential method.
+ * 
+ * @author Phil Burk (C) 2009 Mobileer Inc Translated from 'C' to Java by Lisa
+ *         Tolenti.
+ */
+public class PseudoRandom {
+    // We must shift 1L or else we get a negative number!
+    private static final double INT_TO_DOUBLE = (1.0 / (1L << 31));
+    private long seed = 99887766;
+
+    /**
+     * Create an instance of SynthRandom.
+     */
+    public PseudoRandom() {
+        this(new Random().nextInt());
+    }
+
+    /**
+     * Create an instance of PseudoRandom.
+     */
+    public PseudoRandom(int seed) {
+        setSeed(seed);
+    }
+
+    public void setSeed(int seed) {
+        this.seed = ((long) seed) & 0xFFFFFFFF;
+    }
+
+    public int getSeed() {
+        return (int) seed;
+    }
+
+    /**
+     * Returns the next random double from 0.0 to 1.0
+     * 
+     * @return value from 0.0 to 1.0
+     */
+    public double random() {
+        int positiveInt = nextRandomInteger() & 0x7FFFFFFF;
+        return positiveInt * INT_TO_DOUBLE;
+    }
+
+    /**
+     * Returns the next random double from -1.0 to 1.0
+     * 
+     * @return value from -1.0 to 1.0
+     */
+    public double nextRandomDouble() {
+        return nextRandomInteger() * INT_TO_DOUBLE;
+    }
+
+    /** Calculate random 32 bit number using linear-congruential method. */
+    public int nextRandomInteger() {
+        long rand = (seed * 196314165) + 907633515;
+        seed = rand & 0x00000000FFFFFFFFL;
+        return (int) rand;
+    }
+
+    public int choose(int range) {
+        long bigRandom = nextRandomInteger() & 0x7FFFFFFF;
+        long temp = bigRandom * range;
+        return (int) (temp >> 31);
+    }
+}