Implement Unison Mode using multiple additional TGs

src/config.h

@@ -47,17 +47,17 @@ class CConfig		// Configuration for MiniDexed
 #if (RASPPI==4 || RASPPI==5)
 	// Pi 4 and 5 quad core
 	// These are max values, default is to support 8 in total with optional 16 TGs
-	static const unsigned TGsCore1 = 2;		// process 2 TGs on core 1
-	static const unsigned TGsCore23 = 3;		// process 3 TGs on core 2 and 3 each
-	static const unsigned TGsCore1Opt = 2;		// process optional additional 2 TGs on core 1
-	static const unsigned TGsCore23Opt = 3;		// process optional additional 3 TGs on core 2 and 3 each
+	static const unsigned TGsCore1 = 2*4;		// process 2 TGs on core 1
+	static const unsigned TGsCore23 = 3*4;		// process 3 TGs on core 2 and 3 each
+	static const unsigned TGsCore1Opt = 2*4;		// process optional additional 2 TGs on core 1
+	static const unsigned TGsCore23Opt = 3*4;		// process optional additional 3 TGs on core 2 and 3 each
 	static const unsigned MinToneGenerators = TGsCore1 + 2*TGsCore23;
 	static const unsigned AllToneGenerators = TGsCore1 + TGsCore1Opt + 2*TGsCore23 + 2*TGsCore23Opt;
 	static const unsigned DefToneGenerators = MinToneGenerators;
 #else
 	// Pi 2 or 3 quad core
-	static const unsigned TGsCore1 = 2;		// process 2 TGs on core 1
-	static const unsigned TGsCore23 = 3;		// process 3 TGs on core 2 and 3 each
+	static const unsigned TGsCore1 = 2*4;		// process 2 TGs on core 1
+	static const unsigned TGsCore23 = 3*4;		// process 3 TGs on core 2 and 3 each
 	static const unsigned TGsCore1Opt = 0;
 	static const unsigned TGsCore23Opt = 0;
 	static const unsigned MinToneGenerators = TGsCore1 + 2*TGsCore23;

src/effect_mixer.hpp

@@ -55,6 +55,22 @@ template <int NN> class AudioMixer
 		multiplier[channel] = powf(gain, 4); // see: https://www.dr-lex.be/info-stuff/volumecontrols.html#ideal2
 	}
 
+	// Add a raw parameter to allow bypassing the powf(gain, 4) curve
+	void gain(uint8_t channel, float32_t gain, bool raw)
+	{
+		if (channel >= NN) return;
+
+		if (gain > MAX_GAIN)
+			gain = MAX_GAIN;
+		else if (gain < MIN_GAIN)
+			gain = MIN_GAIN;
+		if (raw) {
+			multiplier[channel] = gain;
+		} else {
+			multiplier[channel] = powf(gain, 4); // see: https://www.dr-lex.be/info-stuff/volumecontrols.html#ideal2
+		}
+	}
+
 	void gain(float32_t gain)
 	{
 		for (uint8_t i = 0; i < NN; i++)