diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3101337..5089f36 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,8 +7,8 @@ if(MSVC)
     set(CMAKE_CXX_FLAGS_DEBUG "/W4 /DEBUG:FASTLINK /fp:fast")
     set(CMAKE_CXX_FLAGS_RELEASE "/W4 /O2 /fp:fast /DNDEBUG")
 else()
-    set(CMAKE_CXX_FLAGS_DEBUG "-Wall -g -ffast-math")
-    set(CMAKE_CXX_FLAGS_RELEASE "-Wall -Ofast -DNDEBUG")
+    set(CMAKE_CXX_FLAGS_DEBUG "-Wall -Wextra -Wdouble-promotion -g -ffast-math")
+    set(CMAKE_CXX_FLAGS_RELEASE "-Wall -Wextra -Wdouble-promotion  -Ofast -DNDEBUG")
 endif()
 
 if(WIN32)
@@ -53,3 +53,6 @@ target_include_directories(main PRIVATE lib/portmidi/porttime)
 
 target_link_libraries(main PRIVATE wxbase)
 target_link_libraries(main PRIVATE wxcore)
+
+add_custom_target(synth)
+add_dependencies(synth main genluts)
diff --git a/include/synth/channel.h b/include/synth/channel.h
index 4ac9163..10cfac1 100644
--- a/include/synth/channel.h
+++ b/include/synth/channel.h
@@ -25,7 +25,7 @@ public:
     void control(int cc, int val);
 
     frame tick() {
-        frame out{0};
+        frame out{0, 0};
         float lfo = sin(lfoPhase);
         Voice** voices = voiceManager->getChannelVoices(number);
         for(Voice** voice = voices; *voice != NULL; ++voice) {
@@ -34,7 +34,7 @@ public:
         out *= volume;
 
         lfoPhase += settings.lfoStep;
-        while(lfoPhase >= PIx2) {
+        while(lfoPhase >= (float) PIx2) {
             lfoPhase -= PIx2;
         }
 
diff --git a/include/synth/dsp/adsr.h b/include/synth/dsp/adsr.h
index e6f70eb..ea24c50 100644
--- a/include/synth/dsp/adsr.h
+++ b/include/synth/dsp/adsr.h
@@ -77,7 +77,7 @@ private:
     float last;
 
     float curve(float gain) {
-        return 0.5 - 0.5 * cos(clamp(gain * M_PI, 0, M_PI));
+        return 0.5f - 0.5f * cosf(clamp(gain * (float) M_PI, 0.f, M_PI));
     }
 };
 
diff --git a/include/synth/dsp/filter.h b/include/synth/dsp/filter.h
index 077d68d..f993beb 100644
--- a/include/synth/dsp/filter.h
+++ b/include/synth/dsp/filter.h
@@ -10,12 +10,16 @@
 #include "../globals.h"
 #include "util.h"
 
-#define FILTER_K_BASE 6.214608098422192
+#define FILTER_OVERSAMPLE   4
+#define FILTER_K_MIN_FREQ   20.0f
+#define FILTER_K_MAX_FREQ   15000.0f
+#define FILTER_K_BASE       logf(FILTER_K_MAX_FREQ / FILTER_K_MIN_FREQ)
+#define FILTER_K_SCALE      (2.f * FILTER_K_MIN_FREQ / (FILTER_OVERSAMPLE * SAMPLE_RATE))
 
+#define K_LUT_SIZE 64
 #ifdef USE_LUTS
 
-    #define K_LUT_SIZE 64
-    
+
     extern float kLUT[K_LUT_SIZE];
 
     inline float freqToK(float x) {
@@ -27,13 +31,13 @@
 #else
 
     inline float freqToK(float x) {
-        return tan(M_PI_4 * 0.002 * exp(x * FILTER_K_BASE));
+        return tanf((float) M_PI_2 * std::min(0.5f, FILTER_K_SCALE * expf(x * FILTER_K_BASE)));
     }
 
 #endif
 
 inline float noteToFltFreq(float note) {
-    return ((note - 69) / 12.0) / (FILTER_K_BASE * M_LOG2E);
+    return ((note - 69) / 12.0f) / (FILTER_K_BASE * (float) M_LOG2E);
 }
 
 class SVF12 {
@@ -64,6 +68,28 @@ public:
     }
 };
 
+class Oversampler {
+private:
+    int times;
+    float kK, kQ = (float) M_SQRT1_2;
+    SVF12 aa1, aa2;
+
+public:
+    Oversampler(int times) : times(times), kK(tanf((float) M_PI_2 * 1.0f / times)) {}
+
+    inline float tick(float in, std::function<float(float)> process) {
+        if(times < 2) {
+            return process(in);
+        } else {
+            float out = aa2.tick(aa1.tick(times * process(in), kK, kQ).lp, kK, kQ).lp;
+            for(int i = 1; i < times; ++i) {
+                aa2.tick(aa1.tick(process(0), kK, kQ).lp, kK, kQ);
+            }
+            return out;
+        }
+    }
+};
+
 // 12 and 24 dB/oct
 class Filter {
 public:
@@ -88,27 +114,32 @@ public:
 private:
     Settings const * settings;
     SVF12 fltA, fltB;
+    Oversampler os{FILTER_OVERSAMPLE};
 
 public:
     void assign(Settings const * settings);
     
     inline float tick(float in, float freqAdd) {
-        float freq = clamp(settings->freq + freqAdd, 0, 1);
-        //float kK = tan(M_PI_4 * clamp(0.002 * exp(freq * FILTER_K_BASE), 0, 1));
+        float freq = clamp(settings->freq + freqAdd, 0.f, 1.f);
         float kK = freqToK(freq);
-        float kQ = M_SQRT1_2 + settings->res;
-        
-        SVF12::Output outA = fltA.tick(in, kK, kQ);
-
-        switch(settings->type) {
-            case TYPE_LP:
-                return settings->slope == SLOPE_24 ? fltB.tick(outA.lp, kK, kQ).lp : outA.lp;
-            case TYPE_BP:
-                return settings->slope == SLOPE_24 ? fltB.tick(outA.bp, kK, kQ).bp : outA.bp;           
-            case TYPE_HP:
-                return settings->slope == SLOPE_24 ? fltB.tick(outA.hp, kK, kQ).hp : outA.hp;
-        }
+        float kQ = (float) M_SQRT1_2 + settings->res;
+
+        return os.tick(in, [this, kK, kQ](float oin) {
+            SVF12::Output outA = fltA.tick(oin, kK, kQ);
+
+            switch(settings->type) {
+                case TYPE_LP:
+                    return settings->slope == SLOPE_24 ? fltB.tick(outA.lp, kK, kQ).lp : outA.lp;
+                case TYPE_BP:
+                    return settings->slope == SLOPE_24 ? fltB.tick(outA.bp, kK, kQ).bp : outA.bp;           
+                case TYPE_HP:
+                    return settings->slope == SLOPE_24 ? fltB.tick(outA.hp, kK, kQ).hp : outA.hp;
+                default:
+                    return oin;
+            }
+        });
     }
 };
 
+
 #endif
\ No newline at end of file
diff --git a/include/synth/dsp/oscillator.h b/include/synth/dsp/oscillator.h
index 974ead7..cd4b3cf 100644
--- a/include/synth/dsp/oscillator.h
+++ b/include/synth/dsp/oscillator.h
@@ -20,7 +20,7 @@ public:
     float driftAmount;
     float driftValue;
 
-    Oscillator() : phase(randPhase()), value(0), driftAmount(0.001), driftValue(0) {}
+    Oscillator() : phase(randPhase()), value(0), driftAmount(0.001f), driftValue(0) {}
 
     void assign(Mode const * mode);
 
@@ -32,21 +32,22 @@ public:
         if (*mode == MODE_SINE) {
             value = sinf(phase); // No harmonics in sine so no aliasing!! No Poly BLEPs needed!
         } else if (*mode == MODE_SAW) {
-            value = (2.0 * phase / PIx2) - 1.0; // Render naive waveshape
+            value = (2.0f * phase / PIx2) - 1.0f; // Render naive waveshape
             value -= polyBlep(t, dt); // Layer output of Poly BLEP on top
         } else if (*mode == MODE_SQUARE) {
-            if (phase < M_PI) {     
+            if (phase < (float) M_PI) {     
                 value = 1.0; // Flip 
             } else { 
                 value = -1.0; // Flop
             }
             value += polyBlep(t, dt); // Layer output of Poly BLEP on top (flip)
-            value -= polyBlep(fmodf(t + 0.5, 1.0), dt); // Layer output of Poly BLEP on top (flop)
+            value -= polyBlep(fmodf(t + 0.5f, 1.0f), dt); // Layer output of Poly BLEP on top (flop)
         }
 
-        driftValue += 0.01 * (randFrac() - 0.5) - 0.00001 * driftValue;
-        phase += phaseStep * (1.0 + driftAmount * driftValue);
-        while(phase >= PIx2) { // wrap if phase angle >=360º
+        //driftValue += 0.01f * (randFrac() - 0.5f) - 0.00001f * driftValue;
+        //phase += phaseStep * (1.0f + driftAmount * driftValue);
+        phase += phaseStep;
+        while(phase >= (float) PIx2) { // wrap if phase angle >=360º
             phase -= PIx2;
         }
         
@@ -59,15 +60,15 @@ public:
         // discontinuities between 0 & 1
         if (t < dt) {
             t /= dt;
-            return t + t - t * t - 1.0;
+            return t + t - t * t - 1.0f;
         }
 
         // t^2/2 +t +1/2
         // -1 <= t <= 0
         // discontinuities between -1 & 0
-        else if (t > 1.0 - dt) {
-            t = (t - 1.0) / dt;
-            return t * t + t + t + 1.0;
+        else if (t > 1.0f - dt) {
+            t = (t - 1.0f) / dt;
+            return t * t + t + t + 1.0f;
         }
 
         // no discontinuities 
diff --git a/include/synth/dsp/util.h b/include/synth/dsp/util.h
index e9a8bce..ab3d1e1 100644
--- a/include/synth/dsp/util.h
+++ b/include/synth/dsp/util.h
@@ -6,12 +6,12 @@
 
 #include "../globals.h"
 
-#define PIx2 (2 * M_PI)
+#define PIx2 ((float )(2 * M_PI))
 
-#ifdef USE_LUTS
-
-    #define NOTE_LUT_SIZE 128
-    #define CENT_LUT_SIZE 128
+//#define USE_NOTE_LUTS
+#define NOTE_LUT_SIZE 128
+#define CENT_LUT_SIZE 128
+#ifdef USE_NOTE_LUTS
 
     extern float noteLUT[NOTE_LUT_SIZE];
     extern float centLUT[CENT_LUT_SIZE];
@@ -25,7 +25,7 @@
 #else
 
     inline float noteToFreq(float note) {
-        return 440 * pow(2, (note - 69) / 12.0);
+        return 440 * powf(2.f, (note - 69) / 12.0f);
     }
 
 #endif
@@ -35,19 +35,19 @@ inline float clamp(float x, float a, float b) {
 }
 
 inline float triangle(float phase) {
-    if(phase < M_PI) {
-        return phase / M_PI_2 - 1;
+    if(phase < (float) M_PI) {
+        return phase / (float) M_PI_2 - 1;
     } else {
-        return 1 - (phase - M_PI) / M_PI_2;
+        return 1 - (phase - (float) M_PI) / (float) M_PI_2;
     }
 }
 
 inline float randFrac() {
-    return (float) rand() / RAND_MAX;
+    return rand() / (float) RAND_MAX;
 }
 
 inline float randPhase() {
-    return PIx2 * randFrac();
+    return (float) PIx2 * randFrac();
 }
 
 #endif
\ No newline at end of file
diff --git a/include/synth/globals.h b/include/synth/globals.h
index c821608..795e9d0 100644
--- a/include/synth/globals.h
+++ b/include/synth/globals.h
@@ -3,6 +3,4 @@
 
 #define SAMPLE_RATE 44100
 
-//#define USE_LUTS
-
 #endif
\ No newline at end of file
diff --git a/include/synth/synth.h b/include/synth/synth.h
index 8cadb02..e9d48c0 100644
--- a/include/synth/synth.h
+++ b/include/synth/synth.h
@@ -8,7 +8,7 @@
 class Synth {
 public:
     Synth() {
-        for(int i = 0; i < 16; ++i) {
+        for(channel_t i = 0; i < 16; ++i) {
             channels[i].number = i;
             channels[i].voiceManager = &voiceManager;
             channels[i].loadPreset(&DEFAULT_PRESET);
@@ -24,7 +24,7 @@ public:
         for(auto& channel : channels) {
             out += channel.tick();
         }
-        out *= 0.100;
+        out *= 0.100f;
         return out;
     }
 
diff --git a/include/synth/voice.h b/include/synth/voice.h
index a860f2c..89999cc 100644
--- a/include/synth/voice.h
+++ b/include/synth/voice.h
@@ -40,16 +40,18 @@ private:
 
 public:
     int note;
+    float unisonPosition;
 
     void reset();
     void assign(Settings const * settings);
-    void noteOn(int note);
+    void noteOn(int note, float unisonPosition = 0);
     void noteOff();
     inline bool isIdle() { return adsrAmp.isIdle(); }
 
     inline float tick(float pitchAdd, float fltFreqAdd) {
-        const float osc1PhaseStep = noteToFreq(note + pitchAdd - settings->oscDetune) * PIx2 / SAMPLE_RATE;
-        const float osc2PhaseStep = noteToFreq(note + pitchAdd + settings->oscDetune + settings->osc2Pitch) * PIx2 / SAMPLE_RATE;
+        const float basePitch = note + pitchAdd + unisonPosition * 4 * settings->oscDetune;
+        const float osc1PhaseStep = noteToFreq(basePitch - settings->oscDetune) * PIx2 / SAMPLE_RATE;
+        const float osc2PhaseStep = noteToFreq(basePitch + settings->oscDetune + settings->osc2Pitch) * PIx2 / SAMPLE_RATE;
         float out = 0;
         out += (1 - settings->oscMix) * osc1.tick(osc1PhaseStep);
         out +=      settings->oscMix  * osc2.tick(osc2PhaseStep);
diff --git a/include/synth/voicemanager.h b/include/synth/voicemanager.h
index 0358ddb..f37e57f 100644
--- a/include/synth/voicemanager.h
+++ b/include/synth/voicemanager.h
@@ -5,7 +5,7 @@
 
 #include "synth/voice.h"
 
-#define NUM_VOICES 16
+#define NUM_VOICES 32
 
 typedef unsigned int channel_t;
 typedef unsigned int serial_t;
diff --git a/src/genluts.cpp b/src/genluts.cpp
index 21fc7bd..2cff62d 100644
--- a/src/genluts.cpp
+++ b/src/genluts.cpp
@@ -1,19 +1,17 @@
 #include <cstdio>
 #include <cmath>
 
-#define USE_LUTS
-
 #include "synth/dsp/filter.h"
 #include "synth/dsp/util.h"
 
 void dumpLUT(const char * filename, const char * identifier, float *lut, size_t size) {
     FILE * f = fopen(filename, "w");
     fprintf(f, "float %s[] = {\n", identifier);
-    for(int i = 0; i < size; ++i) {
+    for(size_t i = 0; i < size; ++i) {
         if(i % 8 == 0) {
             fputs("    ", f);
         }
-        fprintf(f, "%13.7f", lut[i]);
+        fprintf(f, "%13.7ff", (double) lut[i]);
         if(i < size - 1) {
             fputs(", ", f);
         }
@@ -28,19 +26,19 @@ void dumpLUT(const char * filename, const char * identifier, float *lut, size_t
 int main(int argc, char** argv) {
     float kLUT[K_LUT_SIZE];
     for(int i = 0; i < K_LUT_SIZE; ++i) {
-        kLUT[i] = tan(M_PI_4 * 0.002 * exp(i / (K_LUT_SIZE - 1.0) * FILTER_K_BASE));
+        kLUT[i] = tanf((float) M_PI_4 * FILTER_K_SCALE * expf(i / (K_LUT_SIZE - 1.0f) * FILTER_K_BASE));
     }
     dumpLUT("src/synth/dsp/filterlut.cpp", "kLUT", kLUT, K_LUT_SIZE);
 
     float noteLUT[NOTE_LUT_SIZE];
     for(int i = 0; i < NOTE_LUT_SIZE; ++i) {
-        noteLUT[i] = 440 * pow(2, (i - 69) / 12.0);
+        noteLUT[i] = 440 * powf(2.f, (i - 69.f) / 12.0f);
     }
     dumpLUT("src/synth/dsp/notelut.cpp", "noteLUT", noteLUT, NOTE_LUT_SIZE);
 
     float centLUT[CENT_LUT_SIZE];
     for(int i = 0; i < CENT_LUT_SIZE; ++i) {
-        centLUT[i] = pow(2, (float) i / ((CENT_LUT_SIZE - 1) * 12.0));
+        centLUT[i] = pow(2.f, i / ((CENT_LUT_SIZE - 1) * 12.0f));
     }
     dumpLUT("src/synth/dsp/centlut.cpp", "centLUT", centLUT, CENT_LUT_SIZE);
 }
\ No newline at end of file
diff --git a/src/synth/channel.cpp b/src/synth/channel.cpp
index a56b89f..143ee65 100644
--- a/src/synth/channel.cpp
+++ b/src/synth/channel.cpp
@@ -6,7 +6,7 @@
 #include "synth/channel.h"
 
 float timeToStep(float t) {
-    return (1.0 / SAMPLE_RATE) / t;
+    return (1.0f / SAMPLE_RATE) / t;
 }
 
 float ccToA(int x) {
@@ -18,7 +18,7 @@ float ccToDR(int x) {
 }
 
 float ccToLFOStep(int x) {
-    return PIx2 * 0.1 * exp((1 + x) * 6.907755278982137 / 128.0) / SAMPLE_RATE;
+    return PIx2 * 0.1f * expf((1 + x) * 6.907755278982137f / 128.0f) / SAMPLE_RATE;
 }
 
 float ccToLFOPitchMod(int x) {
@@ -55,9 +55,11 @@ void Channel::loadPreset(const Preset * preset) {
 }
 
 void Channel::noteOn(int note, int velocity) {
-    Voice* const voice = voiceManager->get(number);
-    voice->assign(&settings);
-    voice->noteOn(note);
+    for(int i = -1; i <= 1; ++i) {
+        Voice* const voice = voiceManager->get(number);
+        voice->assign(&settings);
+        voice->noteOn(note, i);
+    }
 }
 
 void Channel::noteOff(int note) {
@@ -93,6 +95,7 @@ void Channel::control(int code, int value) {
 
         case CC_FLT_Q: // Timbre / Harmonic Content (Standard MIDI)
             settings.filter.res = value / 31.75;
+            printf("Q=%f\n", M_SQRT1_2 + (double) settings.filter.res);
             break;
 
         case CC_AMP_REL: // Release Time (Standard MIDI)
diff --git a/src/synth/preset.cpp b/src/synth/preset.cpp
index 4893b6b..206ceac 100644
--- a/src/synth/preset.cpp
+++ b/src/synth/preset.cpp
@@ -22,10 +22,10 @@ const Preset DEFAULT_PRESET = {
     },
 
     .modEnv = {
-        .attack = 48,
-        .decay = 100,
+        .attack = 0,
+        .decay = 106,
         .sustain = 0,
-        .release = 100
+        .release = 106
     },
 
     .modEnvFltGain = 56,
diff --git a/src/synth/voice.cpp b/src/synth/voice.cpp
index b82e070..e394be4 100644
--- a/src/synth/voice.cpp
+++ b/src/synth/voice.cpp
@@ -14,8 +14,9 @@ void Voice::assign(Settings const * settings) {
     filter.assign(&settings->filter);
 }
 
-void Voice::noteOn(int note) {
+void Voice::noteOn(int note, float unisonPosition) {
     this->note = note;
+    this->unisonPosition = unisonPosition;
     adsrAmp.noteOn();
     adsrMod.noteOn();
 }
diff --git a/src/synth/voicemanager.cpp b/src/synth/voicemanager.cpp
index 76a1282..7378d83 100644
--- a/src/synth/voicemanager.cpp
+++ b/src/synth/voicemanager.cpp
@@ -1,4 +1,5 @@
 #include <cstdio>
+#include <algorithm>
 
 #include "synth/voicemanager.h"
 
@@ -20,11 +21,11 @@ Voice * VoiceManager::get(channel_t channel) {
     voiceData.serial = serial++;
     voiceData.voice.reset();
 
-    putchar('\n');
-    for(VoiceData& vd : voices) {
-        printf("channel=%d serial=%d idle=%d note=%d\n", vd.channel, vd.serial, vd.voice.isIdle(), vd.voice.note);
-    }
-    putchar('\n');
+    //putchar('\n');
+    //for(VoiceData& vd : voices) {
+    //    printf("channel=%d serial=%d idle=%d note=%d\n", vd.channel, vd.serial, vd.voice.isIdle(), vd.voice.note);
+    //}
+    //putchar('\n');
 
     return &voiceData.voice;
 }
diff --git a/src/synthapp.cpp b/src/synthapp.cpp
index 97e86fa..6b5d89c 100644
--- a/src/synthapp.cpp
+++ b/src/synthapp.cpp
@@ -50,7 +50,7 @@ static int paCallback(
 
     float *out = (float*) outputBuffer;
 
-    for(int i = 0; i < framesPerBuffer; i++) {
+    for(unsigned long i = 0; i < framesPerBuffer; i++) {
         frame f = app->synth.tick();
         *out++ = f.left;
         *out++ = f.right;