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diff --git a/audio/softsynth/mt32/LA32WaveGenerator.cpp b/audio/softsynth/mt32/LA32WaveGenerator.cpp
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index 0000000000..80650699fb
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+++ b/audio/softsynth/mt32/LA32WaveGenerator.cpp
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+/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
+ * Copyright (C) 2011, 2012, 2013 Dean Beeler, Jerome Fisher, Sergey V. Mikayev
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License as published by
+ *  the Free Software Foundation, either version 2.1 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+//#include <cmath>
+#include "mt32emu.h"
+#include "mmath.h"
+#include "LA32WaveGenerator.h"
+
+#if MT32EMU_ACCURATE_WG == 0
+
+namespace MT32Emu {
+
+static const Bit32u SINE_SEGMENT_RELATIVE_LENGTH = 1 << 18;
+static const Bit32u MIDDLE_CUTOFF_VALUE = 128 << 18;
+static const Bit32u RESONANCE_DECAY_THRESHOLD_CUTOFF_VALUE = 144 << 18;
+static const Bit32u MAX_CUTOFF_VALUE = 240 << 18;
+static const LogSample SILENCE = {65535, LogSample::POSITIVE};
+
+Bit16u LA32Utilites::interpolateExp(const Bit16u fract) {
+	Bit16u expTabIndex = fract >> 3;
+	Bit16u extraBits = ~fract & 7;
+	Bit16u expTabEntry2 = 8191 - Tables::getInstance().exp9[expTabIndex];
+	Bit16u expTabEntry1 = expTabIndex == 0 ? 8191 : (8191 - Tables::getInstance().exp9[expTabIndex - 1]);
+	return expTabEntry2 + (((expTabEntry1 - expTabEntry2) * extraBits) >> 3);
+}
+
+Bit16s LA32Utilites::unlog(const LogSample &logSample) {
+	//Bit16s sample = (Bit16s)EXP2F(13.0f - logSample.logValue / 1024.0f);
+	Bit32u intLogValue = logSample.logValue >> 12;
+	Bit16u fracLogValue = logSample.logValue & 4095;
+	Bit16s sample = interpolateExp(fracLogValue) >> intLogValue;
+	return logSample.sign == LogSample::POSITIVE ? sample : -sample;
+}
+
+void LA32Utilites::addLogSamples(LogSample &logSample1, const LogSample &logSample2) {
+	Bit32u logSampleValue = logSample1.logValue + logSample2.logValue;
+	logSample1.logValue = logSampleValue < 65536 ? (Bit16u)logSampleValue : 65535;
+	logSample1.sign = logSample1.sign == logSample2.sign ? LogSample::POSITIVE : LogSample::NEGATIVE;
+}
+
+Bit32u LA32WaveGenerator::getSampleStep() {
+	// sampleStep = EXP2F(pitch / 4096.0f + 4.0f)
+	Bit32u sampleStep = LA32Utilites::interpolateExp(~pitch & 4095);
+	sampleStep <<= pitch >> 12;
+	sampleStep >>= 8;
+	sampleStep &= ~1;
+	return sampleStep;
+}
+
+Bit32u LA32WaveGenerator::getResonanceWaveLengthFactor(Bit32u effectiveCutoffValue) {
+	// resonanceWaveLengthFactor = (Bit32u)EXP2F(12.0f + effectiveCutoffValue / 4096.0f);
+	Bit32u resonanceWaveLengthFactor = LA32Utilites::interpolateExp(~effectiveCutoffValue & 4095);
+	resonanceWaveLengthFactor <<= effectiveCutoffValue >> 12;
+	return resonanceWaveLengthFactor;
+}
+
+Bit32u LA32WaveGenerator::getHighLinearLength(Bit32u effectiveCutoffValue) {
+	// Ratio of positive segment to wave length
+	Bit32u effectivePulseWidthValue = 0;
+	if (pulseWidth > 128) {
+		effectivePulseWidthValue = (pulseWidth - 128) << 6;
+	}
+
+	Bit32u highLinearLength = 0;
+	// highLinearLength = EXP2F(19.0f - effectivePulseWidthValue / 4096.0f + effectiveCutoffValue / 4096.0f) - 2 * SINE_SEGMENT_RELATIVE_LENGTH;
+	if (effectivePulseWidthValue < effectiveCutoffValue) {
+		Bit32u expArg = effectiveCutoffValue - effectivePulseWidthValue;
+		highLinearLength = LA32Utilites::interpolateExp(~expArg & 4095);
+		highLinearLength <<= 7 + (expArg >> 12);
+		highLinearLength -= 2 * SINE_SEGMENT_RELATIVE_LENGTH;
+	}
+	return highLinearLength;
+}
+
+void LA32WaveGenerator::computePositions(Bit32u highLinearLength, Bit32u lowLinearLength, Bit32u resonanceWaveLengthFactor) {
+	// Assuming 12-bit multiplication used here
+	squareWavePosition = resonanceSinePosition = (wavePosition >> 8) * (resonanceWaveLengthFactor >> 4);
+	if (squareWavePosition < SINE_SEGMENT_RELATIVE_LENGTH) {
+		phase = POSITIVE_RISING_SINE_SEGMENT;
+		return;
+	}
+	squareWavePosition -= SINE_SEGMENT_RELATIVE_LENGTH;
+	if (squareWavePosition < highLinearLength) {
+		phase = POSITIVE_LINEAR_SEGMENT;
+		return;
+	}
+	squareWavePosition -= highLinearLength;
+	if (squareWavePosition < SINE_SEGMENT_RELATIVE_LENGTH) {
+		phase = POSITIVE_FALLING_SINE_SEGMENT;
+		return;
+	}
+	squareWavePosition -= SINE_SEGMENT_RELATIVE_LENGTH;
+	resonanceSinePosition = squareWavePosition;
+	if (squareWavePosition < SINE_SEGMENT_RELATIVE_LENGTH) {
+		phase = NEGATIVE_FALLING_SINE_SEGMENT;
+		return;
+	}
+	squareWavePosition -= SINE_SEGMENT_RELATIVE_LENGTH;
+	if (squareWavePosition < lowLinearLength) {
+		phase = NEGATIVE_LINEAR_SEGMENT;
+		return;
+	}
+	squareWavePosition -= lowLinearLength;
+	phase = NEGATIVE_RISING_SINE_SEGMENT;
+}
+
+void LA32WaveGenerator::advancePosition() {
+	wavePosition += getSampleStep();
+	wavePosition %= 4 * SINE_SEGMENT_RELATIVE_LENGTH;
+
+	Bit32u effectiveCutoffValue = (cutoffVal > MIDDLE_CUTOFF_VALUE) ? (cutoffVal - MIDDLE_CUTOFF_VALUE) >> 10 : 0;
+	Bit32u resonanceWaveLengthFactor = getResonanceWaveLengthFactor(effectiveCutoffValue);
+	Bit32u highLinearLength = getHighLinearLength(effectiveCutoffValue);
+	Bit32u lowLinearLength = (resonanceWaveLengthFactor << 8) - 4 * SINE_SEGMENT_RELATIVE_LENGTH - highLinearLength;
+	computePositions(highLinearLength, lowLinearLength, resonanceWaveLengthFactor);
+
+	// resonancePhase computation hack
+	*(int*)&resonancePhase = ((resonanceSinePosition >> 18) + (phase > POSITIVE_FALLING_SINE_SEGMENT ? 2 : 0)) & 3;
+}
+
+void LA32WaveGenerator::generateNextSquareWaveLogSample() {
+	Bit32u logSampleValue;
+	switch (phase) {
+		case POSITIVE_RISING_SINE_SEGMENT:
+		case NEGATIVE_FALLING_SINE_SEGMENT:
+			logSampleValue = Tables::getInstance().logsin9[(squareWavePosition >> 9) & 511];
+			break;
+		case POSITIVE_FALLING_SINE_SEGMENT:
+		case NEGATIVE_RISING_SINE_SEGMENT:
+			logSampleValue = Tables::getInstance().logsin9[~(squareWavePosition >> 9) & 511];
+			break;
+		case POSITIVE_LINEAR_SEGMENT:
+		case NEGATIVE_LINEAR_SEGMENT:
+		default:
+			logSampleValue = 0;
+			break;
+	}
+	logSampleValue <<= 2;
+	logSampleValue += amp >> 10;
+	if (cutoffVal < MIDDLE_CUTOFF_VALUE) {
+		logSampleValue += (MIDDLE_CUTOFF_VALUE - cutoffVal) >> 9;
+	}
+
+	squareLogSample.logValue = logSampleValue < 65536 ? (Bit16u)logSampleValue : 65535;
+	squareLogSample.sign = phase < NEGATIVE_FALLING_SINE_SEGMENT ? LogSample::POSITIVE : LogSample::NEGATIVE;
+}
+
+void LA32WaveGenerator::generateNextResonanceWaveLogSample() {
+	Bit32u logSampleValue;
+	if (resonancePhase == POSITIVE_FALLING_RESONANCE_SINE_SEGMENT || resonancePhase == NEGATIVE_RISING_RESONANCE_SINE_SEGMENT) {
+		logSampleValue = Tables::getInstance().logsin9[~(resonanceSinePosition >> 9) & 511];
+	} else {
+		logSampleValue = Tables::getInstance().logsin9[(resonanceSinePosition >> 9) & 511];
+	}
+	logSampleValue <<= 2;
+	logSampleValue += amp >> 10;
+
+	// From the digital captures, the decaying speed of the resonance sine is found a bit different for the positive and the negative segments
+	Bit32u decayFactor = phase < NEGATIVE_FALLING_SINE_SEGMENT ? resAmpDecayFactor : resAmpDecayFactor + 1;
+	// Unsure about resonanceSinePosition here. It's possible that dedicated counter & decrement are used. Although, cutoff is finely ramped, so maybe not.
+	logSampleValue += resonanceAmpSubtraction + (((resonanceSinePosition >> 4) * decayFactor) >> 8);
+
+	// To ensure the output wave has no breaks, two different windows are appied to the beginning and the ending of the resonance sine segment
+	if (phase == POSITIVE_RISING_SINE_SEGMENT || phase == NEGATIVE_FALLING_SINE_SEGMENT) {
+		// The window is synchronous sine here
+		logSampleValue += Tables::getInstance().logsin9[(squareWavePosition >> 9) & 511] << 2;
+	} else if (phase == POSITIVE_FALLING_SINE_SEGMENT || phase == NEGATIVE_RISING_SINE_SEGMENT) {
+		// The window is synchronous square sine here
+		logSampleValue += Tables::getInstance().logsin9[~(squareWavePosition >> 9) & 511] << 3;
+	}
+
+	if (cutoffVal < MIDDLE_CUTOFF_VALUE) {
+		// For the cutoff values below the cutoff middle point, it seems the amp of the resonance wave is expotentially decayed
+		logSampleValue += 31743 + ((MIDDLE_CUTOFF_VALUE - cutoffVal) >> 9);
+	} else if (cutoffVal < RESONANCE_DECAY_THRESHOLD_CUTOFF_VALUE) {
+		// For the cutoff values below this point, the amp of the resonance wave is sinusoidally decayed
+		Bit32u sineIx = (cutoffVal - MIDDLE_CUTOFF_VALUE) >> 13;
+		logSampleValue += Tables::getInstance().logsin9[sineIx] << 2;
+	}
+
+	// After all the amp decrements are added, it should be safe now to adjust the amp of the resonance wave to what we see on captures
+	logSampleValue -= 1 << 12;
+
+	resonanceLogSample.logValue = logSampleValue < 65536 ? (Bit16u)logSampleValue : 65535;
+	resonanceLogSample.sign = resonancePhase < NEGATIVE_FALLING_RESONANCE_SINE_SEGMENT ? LogSample::POSITIVE : LogSample::NEGATIVE;
+}
+
+void LA32WaveGenerator::generateNextSawtoothCosineLogSample(LogSample &logSample) const {
+	Bit32u sawtoothCosinePosition = wavePosition + (1 << 18);
+	if ((sawtoothCosinePosition & (1 << 18)) > 0) {
+		logSample.logValue = Tables::getInstance().logsin9[~(sawtoothCosinePosition >> 9) & 511];
+	} else {
+		logSample.logValue = Tables::getInstance().logsin9[(sawtoothCosinePosition >> 9) & 511];
+	}
+	logSample.logValue <<= 2;
+	logSample.sign = ((sawtoothCosinePosition & (1 << 19)) == 0) ? LogSample::POSITIVE : LogSample::NEGATIVE;
+}
+
+void LA32WaveGenerator::pcmSampleToLogSample(LogSample &logSample, const Bit16s pcmSample) const {
+	Bit32u logSampleValue = (32787 - (pcmSample & 32767)) << 1;
+	logSampleValue += amp >> 10;
+	logSample.logValue = logSampleValue < 65536 ? (Bit16u)logSampleValue : 65535;
+	logSample.sign = pcmSample < 0 ? LogSample::NEGATIVE : LogSample::POSITIVE;
+}
+
+void LA32WaveGenerator::generateNextPCMWaveLogSamples() {
+	// This should emulate the ladder we see in the PCM captures for pitches 01, 02, 07, etc.
+	// The most probable cause is the factor in the interpolation formula is one bit less
+	// accurate than the sample position counter
+	pcmInterpolationFactor = (wavePosition & 255) >> 1;
+	Bit32u pcmWaveTableIx = wavePosition >> 8;
+	pcmSampleToLogSample(firstPCMLogSample, pcmWaveAddress[pcmWaveTableIx]);
+	if (pcmWaveInterpolated) {
+		pcmWaveTableIx++;
+		if (pcmWaveTableIx < pcmWaveLength) {
+			pcmSampleToLogSample(secondPCMLogSample, pcmWaveAddress[pcmWaveTableIx]);
+		} else {
+			if (pcmWaveLooped) {
+				pcmWaveTableIx -= pcmWaveLength;
+				pcmSampleToLogSample(secondPCMLogSample, pcmWaveAddress[pcmWaveTableIx]);
+			} else {
+				secondPCMLogSample = SILENCE;
+			}
+		}
+	} else {
+		secondPCMLogSample = SILENCE;
+	}
+	// pcmSampleStep = (Bit32u)EXP2F(pitch / 4096.0f + 3.0f);
+	Bit32u pcmSampleStep = LA32Utilites::interpolateExp(~pitch & 4095);
+	pcmSampleStep <<= pitch >> 12;
+	// Seeing the actual lengths of the PCM wave for pitches 00..12,
+	// the pcmPosition counter can be assumed to have 8-bit fractions
+	pcmSampleStep >>= 9;
+	wavePosition += pcmSampleStep;
+	if (wavePosition >= (pcmWaveLength << 8)) {
+		if (pcmWaveLooped) {
+			wavePosition -= pcmWaveLength << 8;
+		} else {
+			deactivate();
+		}
+	}
+}
+
+void LA32WaveGenerator::initSynth(const bool useSawtoothWaveform, const Bit8u usePulseWidth, const Bit8u useResonance) {
+	sawtoothWaveform = useSawtoothWaveform;
+	pulseWidth = usePulseWidth;
+	resonance = useResonance;
+
+	wavePosition = 0;
+
+	squareWavePosition = 0;
+	phase = POSITIVE_RISING_SINE_SEGMENT;
+
+	resonanceSinePosition = 0;
+	resonancePhase = POSITIVE_RISING_RESONANCE_SINE_SEGMENT;
+	resonanceAmpSubtraction = (32 - resonance) << 10;
+	resAmpDecayFactor = Tables::getInstance().resAmpDecayFactor[resonance >> 2] << 2;
+
+	pcmWaveAddress = NULL;
+	active = true;
+}
+
+void LA32WaveGenerator::initPCM(const Bit16s * const usePCMWaveAddress, const Bit32u usePCMWaveLength, const bool usePCMWaveLooped, const bool usePCMWaveInterpolated) {
+	pcmWaveAddress = usePCMWaveAddress;
+	pcmWaveLength = usePCMWaveLength;
+	pcmWaveLooped = usePCMWaveLooped;
+	pcmWaveInterpolated = usePCMWaveInterpolated;
+
+	wavePosition = 0;
+	active = true;
+}
+
+void LA32WaveGenerator::generateNextSample(const Bit32u useAmp, const Bit16u usePitch, const Bit32u useCutoffVal) {
+	if (!active) {
+		return;
+	}
+
+	amp = useAmp;
+	pitch = usePitch;
+
+	if (isPCMWave()) {
+		generateNextPCMWaveLogSamples();
+		return;
+	}
+
+	// The 240 cutoffVal limit was determined via sample analysis (internal Munt capture IDs: glop3, glop4).
+	// More research is needed to be sure that this is correct, however.
+	cutoffVal = (useCutoffVal > MAX_CUTOFF_VALUE) ? MAX_CUTOFF_VALUE : useCutoffVal;
+
+	generateNextSquareWaveLogSample();
+	generateNextResonanceWaveLogSample();
+	if (sawtoothWaveform) {
+		LogSample cosineLogSample;
+		generateNextSawtoothCosineLogSample(cosineLogSample);
+		LA32Utilites::addLogSamples(squareLogSample, cosineLogSample);
+		LA32Utilites::addLogSamples(resonanceLogSample, cosineLogSample);
+	}
+	advancePosition();
+}
+
+LogSample LA32WaveGenerator::getOutputLogSample(const bool first) const {
+	if (!isActive()) {
+		return SILENCE;
+	}
+	if (isPCMWave()) {
+		return first ? firstPCMLogSample : secondPCMLogSample;
+	}
+	return first ? squareLogSample : resonanceLogSample;
+}
+
+void LA32WaveGenerator::deactivate() {
+	active = false;
+}
+
+bool LA32WaveGenerator::isActive() const {
+	return active;
+}
+
+bool LA32WaveGenerator::isPCMWave() const {
+	return pcmWaveAddress != NULL;
+}
+
+Bit32u LA32WaveGenerator::getPCMInterpolationFactor() const {
+	return pcmInterpolationFactor;
+}
+
+void LA32PartialPair::init(const bool useRingModulated, const bool useMixed) {
+	ringModulated = useRingModulated;
+	mixed = useMixed;
+}
+
+void LA32PartialPair::initSynth(const PairType useMaster, const bool sawtoothWaveform, const Bit8u pulseWidth, const Bit8u resonance) {
+	if (useMaster == MASTER) {
+		master.initSynth(sawtoothWaveform, pulseWidth, resonance);
+	} else {
+		slave.initSynth(sawtoothWaveform, pulseWidth, resonance);
+	}
+}
+
+void LA32PartialPair::initPCM(const PairType useMaster, const Bit16s *pcmWaveAddress, const Bit32u pcmWaveLength, const bool pcmWaveLooped) {
+	if (useMaster == MASTER) {
+		master.initPCM(pcmWaveAddress, pcmWaveLength, pcmWaveLooped, true);
+	} else {
+		slave.initPCM(pcmWaveAddress, pcmWaveLength, pcmWaveLooped, !ringModulated);
+	}
+}
+
+void LA32PartialPair::generateNextSample(const PairType useMaster, const Bit32u amp, const Bit16u pitch, const Bit32u cutoff) {
+	if (useMaster == MASTER) {
+		master.generateNextSample(amp, pitch, cutoff);
+	} else {
+		slave.generateNextSample(amp, pitch, cutoff);
+	}
+}
+
+Bit16s LA32PartialPair::unlogAndMixWGOutput(const LA32WaveGenerator &wg, const LogSample * const ringModulatingLogSample) {
+	if (!wg.isActive() || ((ringModulatingLogSample != NULL) && (ringModulatingLogSample->logValue == SILENCE.logValue))) {
+		return 0;
+	}
+	LogSample firstLogSample = wg.getOutputLogSample(true);
+	LogSample secondLogSample = wg.getOutputLogSample(false);
+	if (ringModulatingLogSample != NULL) {
+		LA32Utilites::addLogSamples(firstLogSample, *ringModulatingLogSample);
+		LA32Utilites::addLogSamples(secondLogSample, *ringModulatingLogSample);
+	}
+	Bit16s firstSample = LA32Utilites::unlog(firstLogSample);
+	Bit16s secondSample = LA32Utilites::unlog(secondLogSample);
+	if (wg.isPCMWave()) {
+		return Bit16s(firstSample + ((Bit32s(secondSample - firstSample) * wg.getPCMInterpolationFactor()) >> 7));
+	}
+	return firstSample + secondSample;
+}
+
+Bit16s LA32PartialPair::nextOutSample() {
+	if (ringModulated) {
+		LogSample slaveFirstLogSample = slave.getOutputLogSample(true);
+		LogSample slaveSecondLogSample = slave.getOutputLogSample(false);
+		Bit16s sample = unlogAndMixWGOutput(master, &slaveFirstLogSample);
+		if (!slave.isPCMWave()) {
+			sample += unlogAndMixWGOutput(master, &slaveSecondLogSample);
+		}
+		if (mixed) {
+			sample += unlogAndMixWGOutput(master, NULL);
+		}
+		return sample;
+	}
+	return unlogAndMixWGOutput(master, NULL) + unlogAndMixWGOutput(slave, NULL);
+}
+
+void LA32PartialPair::deactivate(const PairType useMaster) {
+	if (useMaster == MASTER) {
+		master.deactivate();
+	} else {
+		slave.deactivate();
+	}
+}
+
+bool LA32PartialPair::isActive(const PairType useMaster) const {
+	return useMaster == MASTER ? master.isActive() : slave.isActive();
+}
+
+}
+
+#endif // #if MT32EMU_ACCURATE_WG == 0