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diff --git a/tests/com/jsyn/examples/LongEcho.java b/tests/com/jsyn/examples/LongEcho.java
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+/*
+ * Copyright 2010 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.examples;
+
+import java.io.File;
+import java.io.IOException;
+
+import com.jsyn.JSyn;
+import com.jsyn.Synthesizer;
+import com.jsyn.data.FloatSample;
+import com.jsyn.devices.AudioDeviceManager;
+import com.jsyn.unitgen.ChannelIn;
+import com.jsyn.unitgen.ChannelOut;
+import com.jsyn.unitgen.FixedRateMonoReader;
+import com.jsyn.unitgen.FixedRateMonoWriter;
+import com.jsyn.unitgen.Maximum;
+import com.jsyn.unitgen.Minimum;
+import com.jsyn.util.WaveFileWriter;
+
+/**
+ * Echo the input using a circular buffer in a sample.
+ * 
+ * @author Phil Burk (C) 2010 Mobileer Inc
+ */
+public class LongEcho {
+    final static int DELAY_SECONDS = 4;
+    Synthesizer synth;
+    ChannelIn channelIn;
+    ChannelOut channelOut;
+    FloatSample sample;
+    FixedRateMonoReader reader;
+    FixedRateMonoWriter writer;
+    Minimum minner;
+    Maximum maxxer;
+
+    private void test() throws IOException {
+        // Create a context for the synthesizer.
+        synth = JSyn.createSynthesizer();
+        // Add a tone generator.
+        synth.add(channelIn = new ChannelIn());
+        // Add an output mixer.
+        synth.add(channelOut = new ChannelOut());
+
+        synth.add(minner = new Minimum());
+        synth.add(maxxer = new Maximum());
+        synth.add(reader = new FixedRateMonoReader());
+        synth.add(writer = new FixedRateMonoWriter());
+
+        sample = new FloatSample(44100 * DELAY_SECONDS, 1);
+
+        maxxer.inputB.set(-0.98); // clip
+        minner.inputB.set(0.98);
+
+        // Connect the input to the output.
+        channelIn.output.connect(minner.inputA);
+        minner.output.connect(maxxer.inputA);
+        maxxer.output.connect(writer.input);
+
+        reader.output.connect(channelOut.input);
+
+        // Both stereo.
+        int numInputChannels = 2;
+        int numOutputChannels = 2;
+        synth.start(44100, AudioDeviceManager.USE_DEFAULT_DEVICE, numInputChannels,
+                AudioDeviceManager.USE_DEFAULT_DEVICE, numOutputChannels);
+
+        writer.start();
+        channelOut.start();
+
+        // For a long echo, read cursor should be just in front of the write cursor.
+        reader.dataQueue.queue(sample, 1000, sample.getNumFrames() - 1000);
+        // Loop both forever.
+        reader.dataQueue.queueLoop(sample, 0, sample.getNumFrames());
+        writer.dataQueue.queueLoop(sample, 0, sample.getNumFrames());
+        System.out.println("Start talking. You should hear an echo after " + DELAY_SECONDS
+                + " seconds.");
+        // Sleep a while.
+        try {
+            double time = synth.getCurrentTime();
+            // Sleep for a while
+            synth.sleepUntil(time + 30.0);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        saveEcho(new File("saved_echo.wav"));
+        // Stop everything.
+        synth.stop();
+    }
+
+    private void saveEcho(File file) throws IOException {
+        WaveFileWriter writer = new WaveFileWriter(file);
+        writer.setFrameRate(44100);
+        writer.setSamplesPerFrame(1);
+        writer.setBitsPerSample(16);
+        float[] buffer = new float[sample.getNumFrames()];
+        sample.read(buffer);
+        for (float v : buffer) {
+            writer.write(v);
+        }
+        writer.close();
+    }
+
+    public static void main(String[] args) {
+        try {
+            new LongEcho().test();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}