Introduce MasterVolume (#842)

src/config.cpp

@@ -200,6 +200,8 @@ void CConfig::Load (void)
 	m_bProfileEnabled = m_Properties.GetNumber ("ProfileEnabled", 0) != 0;
 	m_bPerformanceSelectToLoad = m_Properties.GetNumber ("PerformanceSelectToLoad", 1) != 0;
 	m_bPerformanceSelectChannel = m_Properties.GetNumber ("PerformanceSelectChannel", 0);
+
+	m_nMasterVolume = m_Properties.GetNumber ("MasterVolume", 64);
 }
 
 unsigned CConfig::GetToneGenerators (void) const

src/config.h

@@ -239,6 +239,8 @@ public:
 	bool GetPerformanceSelectToLoad (void) const;
 	unsigned GetPerformanceSelectChannel (void) const;
 
+	unsigned GetMasterVolume() const { return m_nMasterVolume; }
+
 private:
 	CPropertiesFatFsFile m_Properties;
 	
@@ -353,6 +355,8 @@ private:
 	bool m_bProfileEnabled;
 	bool m_bPerformanceSelectToLoad;
 	unsigned m_bPerformanceSelectChannel;
+
+	unsigned m_nMasterVolume; // Master volume 0-127
 };
 
 #endif

src/minidexed.cpp

@@ -218,7 +218,8 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 	}
 #endif
 
-	setMasterVolume(1.0);
+	float masterVolNorm = (float)(pConfig->GetMasterVolume()) / 127.0f;
+	setMasterVolume(masterVolNorm);
 
 	// BEGIN setup tg_mixer
 	tg_mixer = new AudioStereoMixer<CConfig::AllToneGenerators>(pConfig->GetChunkSize()/2);
@@ -1807,6 +1808,9 @@ void CMiniDexed::setMasterVolume (float32_t vol)
     else if (vol > 1.0)
         vol = 1.0;
 
+    // Apply logarithmic scaling to match perceived loudness
+    vol = powf(vol, 2.0f);
+
     nMasterVolume = vol;
 }
 

src/minidexed.ini

@@ -13,6 +13,8 @@ ChannelsSwapped=0
 # Engine Type ( 1=Modern ; 2=Mark I ; 3=OPL )
 EngineType=1
 QuadDAC8Chan=0
+# Master Volume (0-127)
+MasterVolume=64
 
 # MIDI
 MIDIBaudRate=31250