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diff --git a/audio/softsynth/mt32/freeverb.h b/audio/softsynth/mt32/freeverb.h
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+++ b/audio/softsynth/mt32/freeverb.h
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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * 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 General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+// Macro for killing denormalled numbers
+//
+// Written by Jezar at Dreampoint, June 2000
+// http://www.dreampoint.co.uk
+// Based on IS_DENORMAL macro by Jon Watte
+// This code is public domain
+
+#ifndef FREEVERB_H
+#define FREEVERB_H
+
+// FIXME: Fix this really ugly hack
+inline float undenormalise(void *sample) {
+	if (((*(unsigned int*)sample) &  0x7f800000) == 0)
+		return 0.0f;
+	return *(float*)sample;
+}
+
+// Comb filter class declaration
+
+class comb {
+public:
+	comb();
+	void setbuffer(float *buf, int size);
+	inline float process(float inp);
+	void mute();
+	void setdamp(float val);
+	float getdamp();
+	void setfeedback(float val);
+	float getfeedback();
+private:
+	float feedback;
+	float filterstore;
+	float damp1;
+	float damp2;
+	float *buffer;
+	int bufsize;
+	int bufidx;
+};
+
+
+// Big to inline - but crucial for speed
+
+inline float comb::process(float input) {
+	float output;
+
+	output = buffer[bufidx];
+	undenormalise(&output);
+
+	filterstore = (output * damp2) + (filterstore * damp1);
+	undenormalise(&filterstore);
+
+	buffer[bufidx] = input + (filterstore * feedback);
+
+	if (++bufidx >= bufsize)
+		bufidx = 0;
+
+	return output;
+}
+
+// Allpass filter declaration
+
+class allpass {
+public:
+	allpass();
+	void setbuffer(float *buf, int size);
+	inline float process(float inp);
+	void mute();
+	void setfeedback(float val);
+	float getfeedback();
+private:
+	float feedback;
+	float *buffer;
+	int bufsize;
+	int bufidx;
+};
+
+
+// Big to inline - but crucial for speed
+
+inline float allpass::process(float input) {
+	float output;
+	float bufout;
+
+	bufout = buffer[bufidx];
+	undenormalise(&bufout);
+
+	output = -input + bufout;
+	buffer[bufidx] = input + (bufout * feedback);
+
+	if (++bufidx >= bufsize)
+		bufidx = 0;
+
+	return output;
+}
+
+
+// Reverb model tuning values
+
+const int	numcombs	= 8;
+const int	numallpasses	= 4;
+const float	muted		= 0;
+const float	fixedgain	= 0.015f;
+const float	scalewet	= 3;
+const float	scaledry	= 2;
+const float	scaledamp	= 0.4f;
+const float	scaleroom	= 0.28f;
+const float	offsetroom	= 0.7f;
+const float	initialroom	= 0.5f;
+const float	initialdamp	= 0.5f;
+const float	initialwet	= 1 / scalewet;
+const float	initialdry	= 0;
+const float	initialwidth	= 1;
+const float	initialmode	= 0;
+const float	freezemode	= 0.5f;
+const int	stereospread	= 23;
+
+// These values assume 44.1KHz sample rate
+// they will probably be OK for 48KHz sample rate
+// but would need scaling for 96KHz (or other) sample rates.
+// The values were obtained by listening tests.
+const int combtuningL1		= 1116;
+const int combtuningR1		= 1116 + stereospread;
+const int combtuningL2		= 1188;
+const int combtuningR2		= 1188 + stereospread;
+const int combtuningL3		= 1277;
+const int combtuningR3		= 1277 + stereospread;
+const int combtuningL4		= 1356;
+const int combtuningR4		= 1356 + stereospread;
+const int combtuningL5		= 1422;
+const int combtuningR5		= 1422 + stereospread;
+const int combtuningL6		= 1491;
+const int combtuningR6		= 1491 + stereospread;
+const int combtuningL7		= 1557;
+const int combtuningR7		= 1557 + stereospread;
+const int combtuningL8		= 1617;
+const int combtuningR8		= 1617 + stereospread;
+const int allpasstuningL1	= 556;
+const int allpasstuningR1	= 556 + stereospread;
+const int allpasstuningL2	= 441;
+const int allpasstuningR2	= 441 + stereospread;
+const int allpasstuningL3	= 341;
+const int allpasstuningR3	= 341 + stereospread;
+const int allpasstuningL4	= 225;
+const int allpasstuningR4	= 225 + stereospread;
+
+
+// Reverb model declaration
+
+class revmodel {
+public:
+	revmodel();
+	void mute();
+	void processmix(float *inputL, float *inputR, float *outputL, float *outputR, long numsamples, int skip);
+	void processreplace(float *inputL, float *inputR, float *outputL, float *outputR, long numsamples, int skip);
+	void setroomsize(float value);
+	float getroomsize();
+	void setdamp(float value);
+	float getdamp();
+	void setwet(float value);
+	float getwet();
+	void setdry(float value);
+	float getdry();
+	void setwidth(float value);
+	float getwidth();
+	void setmode(float value);
+	float getmode();
+private:
+	void update();
+
+	float gain;
+	float roomsize, roomsize1;
+	float damp, damp1;
+	float wet, wet1, wet2;
+	float dry;
+	float width;
+	float mode;
+
+	// The following are all declared inline
+	// to remove the need for dynamic allocation
+	// with its subsequent error-checking messiness
+
+	// Comb filters
+	comb combL[numcombs];
+	comb combR[numcombs];
+
+	// Allpass filters
+	allpass	allpassL[numallpasses];
+	allpass	allpassR[numallpasses];
+
+	// Buffers for the combs
+	float bufcombL1[combtuningL1];
+	float bufcombR1[combtuningR1];
+	float bufcombL2[combtuningL2];
+	float bufcombR2[combtuningR2];
+	float bufcombL3[combtuningL3];
+	float bufcombR3[combtuningR3];
+	float bufcombL4[combtuningL4];
+	float bufcombR4[combtuningR4];
+	float bufcombL5[combtuningL5];
+	float bufcombR5[combtuningR5];
+	float bufcombL6[combtuningL6];
+	float bufcombR6[combtuningR6];
+	float bufcombL7[combtuningL7];
+	float bufcombR7[combtuningR7];
+	float bufcombL8[combtuningL8];
+	float bufcombR8[combtuningR8];
+
+	// Buffers for the allpasses
+	float bufallpassL1[allpasstuningL1];
+	float bufallpassR1[allpasstuningR1];
+	float bufallpassL2[allpasstuningL2];
+	float bufallpassR2[allpasstuningR2];
+	float bufallpassL3[allpasstuningL3];
+	float bufallpassR3[allpasstuningR3];
+	float bufallpassL4[allpasstuningL4];
+	float bufallpassR4[allpasstuningR4];
+};
+
+#endif