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diff --git a/src/com/jsyn/unitgen/SawtoothOscillatorBL.java b/src/com/jsyn/unitgen/SawtoothOscillatorBL.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;
+
+/**
+ * Sawtooth oscillator that uses multiple wave tables for band limiting. This requires more CPU than
+ * a plain SawtoothOscillator but has less aliasing at high frequencies.
+ * 
+ * @author Phil Burk (C) 2009 Mobileer Inc
+ */
+public class SawtoothOscillatorBL extends UnitOscillator {
+    @Override
+    public void generate(int start, int limit) {
+        MultiTable multiTable = MultiTable.getInstance();
+
+        double[] frequencies = frequency.getValues();
+        double[] amplitudes = amplitude.getValues();
+        double[] outputs = output.getValues();
+        // Variables have a single value.
+        double currentPhase = phase.getValue();
+
+        double phaseIncrement = convertFrequencyToPhaseIncrement(frequencies[0]);
+        double positivePhaseIncrement = Math.abs(phaseIncrement);
+        // This is very expensive so we moved it outside the loop.
+        // Try to optimize it with a table lookup.
+        double flevel = multiTable.convertPhaseIncrementToLevel(positivePhaseIncrement);
+
+        for (int i = start; i < limit; i++) {
+            /* Generate sawtooth phasor to provide phase for sine generation. */
+            phaseIncrement = convertFrequencyToPhaseIncrement(frequencies[i]);
+            currentPhase = incrementWrapPhase(currentPhase, phaseIncrement);
+            positivePhaseIncrement = Math.abs(phaseIncrement);
+
+            double val = generateBL(multiTable, currentPhase, positivePhaseIncrement, flevel, i);
+
+            outputs[i] = val * amplitudes[i];
+        }
+
+        // Value needs to be saved for next time.
+        phase.setValue(currentPhase);
+    }
+
+    protected double generateBL(MultiTable multiTable, double currentPhase,
+            double positivePhaseIncrement, double flevel, int i) {
+        /* Calculate table level then use it for lookup. */
+        return multiTable.calculateSawtooth(currentPhase, positivePhaseIncrement, flevel);
+    }
+
+}