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diff --git a/audio/softsynth/mt32/Analog.h b/audio/softsynth/mt32/Analog.h
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+/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
+ * Copyright (C) 2011, 2012, 2013, 2014 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/>.
+ */
+
+#ifndef MT32EMU_ANALOG_H
+#define MT32EMU_ANALOG_H
+
+#include "mt32emu.h"
+
+namespace MT32Emu {
+
+class AbstractLowPassFilter;
+
+/* Analog class is dedicated to perform fair emulation of analogue circuitry of hardware units that is responsible
+ * for processing output signal after the DAC. It appears that the analogue circuit labeled "LPF" on the schematic
+ * also applies audible changes to the signal spectra. There is a significant boost of higher frequencies observed
+ * aside from quite poor attenuation of the mirror spectra above 16 kHz which is due to a relatively low filter order.
+ *
+ * As the final mixing of multiplexed output signal is performed after the DAC, this function is migrated here from Synth.
+ * Saying precisely, mixing is performed within the LPF as the entrance resistors are actually components of a LPF
+ * designed using the multiple feedback topology. Nevertheless, the schematic separates them.
+ */
+class Analog {
+public:
+	Analog(AnalogOutputMode mode, const ControlROMFeatureSet *controlROMFeatures);
+	~Analog();
+	void process(Sample **outStream, const Sample *nonReverbLeft, const Sample *nonReverbRight, const Sample *reverbDryLeft, const Sample *reverbDryRight, const Sample *reverbWetLeft, const Sample *reverbWetRight, const Bit32u outLength);
+	unsigned int getOutputSampleRate() const;
+	Bit32u getDACStreamsLength(Bit32u outputLength) const;
+	void setSynthOutputGain(float synthGain);
+	void setReverbOutputGain(float reverbGain, bool mt32ReverbCompatibilityMode);
+
+private:
+	AbstractLowPassFilter &leftChannelLPF;
+	AbstractLowPassFilter &rightChannelLPF;
+	SampleEx synthGain;
+	SampleEx reverbGain;
+
+	Analog(Analog &);
+};
+
+}
+
+#endif