diff --git a/sketch/sketch.ino b/sketch/sketch.ino
index 69ee235..c525e2a 100644
--- a/sketch/sketch.ino
+++ b/sketch/sketch.ino
@@ -22,17 +22,24 @@ float ABS_VOL = 0.5f;
 float decay = 0.99998f;
 Adafruit_SSD1306 display(OLED_W, OLED_H, &Wire);
 // ----- Menu Functions
-  int sound = 0; //Default voice
-  String sounds[6] = {"Saw+Sine", "Sine", "Saw", "Triangle", "Square", "Noise"};
-  int sound_count = sizeof(sounds)/sizeof(sounds[0]);
+int sound = 0;  //Default voice
+String sounds[6] = { "Saw+Sine", "Sine", "Saw", "Triangle", "Square", "Noise" };
+int sound_count = sizeof(sounds) / sizeof(sounds[0]);
 
-  // Modes
-  int mode = 0;
-  String mode_names[4] = {"Vol", "Sou", "Oct", "Env"};
-  int mode_count = sizeof(mode_names)/sizeof(mode_names[0]);
+// Modes
+int mode = 0;
+String mode_names[7] = { "Vol", "Sou", "Oct", "Env", "Arp", "ArpΔ", "Arp"};
+int mode_count = sizeof(mode_names) / sizeof(mode_names[0]);
 
-  // Octave
-  int octave = 2;
+// Octave
+int octave = 2;
+
+// Arpeggio
+//int arp_pattern[5] = {1 ,3 ,5 ,3 ,1 };
+int arp_pattern[5] = {0 ,4 ,7 ,3 ,1 };
+int arpeggio = 1;  // 0 = Off, 1 =
+int arp_notes = 3; // Now many notes to arpeggiate
+int arp_delay = 150; // 300 ms
 
 
 // ---- Audio ----
@@ -42,14 +49,14 @@ constexpr uint8_t CHANNELS = 1;
 constexpr uint8_t BITS = 16;
 
 // ----- Reverb -----
-constexpr int reverb_time = 200; // 200 ms.
-constexpr int reverb_samples = (int)(reverb_time/1000*SAMPLE_RATE);
+constexpr int reverb_time = 200;  // 200 ms.
+constexpr int reverb_samples = (int)(reverb_time / 1000 * SAMPLE_RATE);
 float reverbqueue[reverb_samples] = {};
 float reverb_fade = 0.3f;
 
 // ---- Matrix ----
-const int X_PINS[4] = {8, 9, 10, 7};
-const int Y_PINS[4] = {19, 20, 21, 22};
+const int X_PINS[4] = { 8, 9, 10, 7 };
+const int Y_PINS[4] = { 19, 20, 21, 22 };
 
 // ---- Synth ----
 constexpr int MAX_VOICES = 200;
@@ -58,10 +65,10 @@ constexpr int MAX_VOICES = 200;
    NOTES
    ========================================================= */
 
-const char* noteNames[12] = {
-  "C","C#","D","D#",
-  "E","F","F#","G",
-  "G#","A","A#","B"
+const char *noteNames[12] = {
+  "C", "C#", "D", "D#",
+  "E", "F", "F#", "G",
+  "G#", "A", "A#", "B"
 };
 
 float noteFreq[12];
@@ -80,10 +87,13 @@ void initNotes() {
 struct Voice {
   bool active = false;
   float freq = 0;
+  float startFreq = 0;
   float phase1 = 0;
   float phase2 = 0;
   float env = 0;
   float amp = 0;
+  long  arp_time = 0;
+  int   arp_position = 0;
 };
 
 Voice voices[MAX_VOICES];
@@ -92,8 +102,11 @@ void noteOn(float freq) {
   for (auto &v : voices) {
     if (!v.active) {
       v.active = true;
-      v.freq = freq*(funcKey ? 1.25f : 1.0f);
+      v.freq = freq;
+      v.startFreq = freq;
       v.env = VOL;
+      v.arp_time = millis();
+      v.arp_position = 0;
       v.phase1 = 0.5f;
       v.phase2 = 0.5f;
       return;
@@ -103,7 +116,7 @@ void noteOn(float freq) {
 
 void noteOff(float freq) {
   for (auto &v : voices) {
-    if (v.active && fabs(v.freq - freq) < 0.01f) {
+    if (v.active && fabs(v.startFreq - freq) < 0.01f) {
       v.active = false;
     }
   }
@@ -112,51 +125,56 @@ void noteOff(float freq) {
 float sineWave(float phase) {
   // Convert phase (0-1) to radians (0-2π)
   float radians = phase * 2.0f * 3.14156f;
-  
+
   // Generate sine value (-1 to 1)
   float sineValue = sin(radians);
-  
+
   // Map from (-1 to 1) to (0 to 1)
   float output = (sineValue + 1.0f) / 2.0f;
-  
+
   return output;
 }
 
-float handleReverb(float val){
-  for(int i = 0; i<reverb_samples-1; i++){
-    reverbqueue[i] = reverbqueue[i+1];
+float handleReverb(float val) {
+  for (int i = 0; i < reverb_samples - 1; i++) {
+    reverbqueue[i] = reverbqueue[i + 1];
   }
-  reverbqueue[reverb_samples-1] = val;
-  return reverbqueue[0]*reverb_fade;
+  reverbqueue[reverb_samples - 1] = val;
+  return reverbqueue[0] * reverb_fade;
 }
 
 
-float wavetable[16] = {0.2f,0.4f,0.9f,0.2f,0.4f,0.9f,0.2f,0.4f,0.9f,0.2f,0.4f,0.9f,0.2f,0.4f,0.9f,0.2f};
+float wavetable[16] = { 0.2f, 0.4f, 0.9f, 0.2f, 0.4f, 0.9f, 0.2f, 0.4f, 0.9f, 0.2f, 0.4f, 0.9f, 0.2f, 0.4f, 0.9f, 0.2f };
 float wavetableInt[1024] = {};
 
 
-int genWaveTable(){
+int genWaveTable() {
   int size = 16;
   int newSize = 1024;
-  int div = newSize/size;
-  for(int s = 0; s<size-1; s++){
-    for(int i = 0; i<div; i++){
-      wavetableInt[(s*div)+i] = wavetable[s]+((wavetable[s+1]-wavetable[s])*(i/div));
+  int div = newSize / size;
+  for (int s = 0; s < size - 1; s++) {
+    for (int i = 0; i < div; i++) {
+      wavetableInt[(s * div) + i] = wavetable[s] + ((wavetable[s + 1] - wavetable[s]) * (i / div));
     }
   }
   return 0;
 }
+
+
+float transposeSemitones(float freq, int semitones) {
+    return freq * powf(2.0f, semitones / 12.0f);
+}
 /* =========================================================
    SYNTH STREAM
    ========================================================= */
 
-class JunoStream : public Stream {
+class SynthStream : public Stream {
 public:
   uint8_t frame[4];
   uint8_t index = 4;
 
   float lp = 0.0f;
-  float cutoff = 1.0f*VOL;
+  float cutoff = 1.0f * VOL;
   float detune = 0.004f;
   //float detune = 0.006f;
 
@@ -167,7 +185,9 @@ public:
   float scope[128]{};
   int scopeIndex = 0;
 
-  int available() override { return 4; }
+  int available() override {
+    return 4;
+  }
 
   int read() override {
     if (index >= 4) {
@@ -177,8 +197,12 @@ public:
     return frame[index++];
   }
 
-  int peek() override { return -1; }
-  size_t write(uint8_t) override { return 0; }
+  int peek() override {
+    return -1;
+  }
+  size_t write(uint8_t) override {
+    return 0;
+  }
 
 private:
   void generate() {
@@ -188,11 +212,18 @@ private:
       if (!v.active) continue;
       float osc = 0.0f;
 
+
+      if (arpeggio>0 && (millis()-v.arp_time)>arp_delay){
+        v.arp_time = millis();
+        v.arp_position++;
+        v.arp_position = v.arp_position % arp_notes;
+        v.freq = transposeSemitones(v.startFreq, arp_pattern[v.arp_position]);
+      }
       // Defined voices
-      switch(sound){
+      switch (sound) {
         // Saw+Sine
         case 0:
-          osc = (sineWave(v.phase1)+sineWave(v.phase2)+wavetableInt[(int)floor(1024.0f*v.phase2)])/3.0f;
+          osc = (sineWave(v.phase1) + sineWave(v.phase2) + wavetableInt[(int)floor(1024.0f * v.phase2)]) / 3.0f;
           break;
         // Sine Wave
         case 1:
@@ -204,20 +235,20 @@ private:
           break;
         // Triangle Wave
         case 3:
-          osc = abs((v.phase1*2)-1.0f);
+          osc = abs((v.phase1 * 2) - 1.0f);
           break;
         // Square Wave
         case 4:
-          osc = (v.phase1>0.5f);
+          osc = (v.phase1 > 0.5f);
           break;
-        // Noise 
-        case 5: 
-          osc = sineWave(v.phase1)+(random(-1000,1000)/2000.0f);
+        // Noise
+        case 5:
+          osc = sineWave(v.phase1) + (random(-1000, 1000) / 2000.0f);
           break;
       }
-      
+
       v.phase1 += v.freq / SAMPLE_RATE;
-      v.phase2 += (v.freq *1.0f * (1.25f + detune)) / SAMPLE_RATE;
+      v.phase2 += (v.freq * 1.0f * (1.25f + detune)) / SAMPLE_RATE;
       //v.phase2 += (v.freq *1.25f * (1.0f + detune)) / SAMPLE_RATE;
       if (v.phase1 >= 1) v.phase1 -= 1;
       if (v.phase2 >= 1) v.phase2 -= 1;
@@ -228,10 +259,13 @@ private:
 
       mix += osc * v.amp;
     }
+    // Handle reverb
+    mix = (handleReverb(mix) + mix) / 2.0f;
+
 
     lp += cutoff * (mix - lp);
     float out = lp * 0.4f;
-    //out = (handleReverb(out)+out)/2.0f;
+
 
     int r = (delayIndex - 480 + DELAY_SAMPLES) % DELAY_SAMPLES;
     float ch = out + delayL[r] * 0.6f;
@@ -256,7 +290,7 @@ private:
    ========================================================= */
 
 I2SStream i2s;
-JunoStream synth;
+SynthStream synth;
 StreamCopy copier(i2s, synth);
 
 /* =========================================================
@@ -269,7 +303,7 @@ uint16_t scanMatrix() {
 
   for (int x = 0; x < 4; x++) {
     digitalWrite(X_PINS[x], HIGH);
-    delayMicroseconds(5);
+    delayMicroseconds(10);
 
     for (int y = 0; y < 4; y++) {
       if (digitalRead(Y_PINS[y])) {
@@ -288,61 +322,62 @@ uint16_t keys = 0;
 uint16_t changed = keys ^ lastKeys;
 
 // Handle key scanning and menus
-void handleInputs(){
+void handleInputs() {
   lastKeys = keys;
   keys = scanMatrix();
   changed = keys ^ lastKeys;
   for (int i = 0; i < 16; i++) {
     if (changed & (1 << i)) {
       if (i < 12) {
-        if ((keys & (1 << i))){ 
+        if ((keys & (1 << i))) {
           noteOn(noteFreq[i]);
-        }else{
+        } else {
           noteOff(noteFreq[i]);
         }
       } else {
         funcKey = (keys & (1 << 12));
         // If Enter key pressed
-        if(keys & (1 << 14)){
-          mode = mode+1;
+        if (keys & (1 << 14)) {
+          mode = mode + 1;
           mode = mode % mode_count;
         }
         // If Left key is pressed
-        if(keys & (1 << 13)){
-          switch(mode){
+        if (keys & (1 << 13)) {
+          switch (mode) {
             case 0:  // Volume
-              if(VOL > 0.1f){ VOL-=0.1f; } break;
-            case 1: // Sound
-              sound = sound - 1;
-              if( sound < 0 ){sound = sound_count-1;}
+              if (VOL > 0.1f) { VOL -= 0.1f; }
               break;
-            case 2: // Octave
-              if(octave>1){ octave = octave-1;}
+            case 1:  // Sound
+              sound = sound - 1;
+              if (sound < 0) { sound = sound_count - 1; }
+              break;
+            case 2:  // Octave
+              if (octave > 1) { octave = octave - 1; }
               initNotes();
               break;
-            case 3: // Envelope
-              // TODO 
+            case 3:  // Envelope
+              // TODO
               break;
           }
-            
+
           // If Right key is pressed
-          }else if((keys & (1 << 15))){
-            switch(mode){
-              case 0:  // Volume
-                if(VOL<1.0f){VOL+=0.1f;}
-                break;
-              case 1: // Sound
-                sound = sound + 1;
-                sound = sound % sound_count;
-                break;
-              case 2: // Octave
-                if(octave<8){octave = octave + 1;}
-                initNotes();
-                break;
-              case 3: // Envelope
-                break;
-            }
+        } else if ((keys & (1 << 15))) {
+          switch (mode) {
+            case 0:  // Volume
+              if (VOL < 1.0f) { VOL += 0.1f; }
+              break;
+            case 1:  // Sound
+              sound = sound + 1;
+              sound = sound % sound_count;
+              break;
+            case 2:  // Octave
+              if (octave < 8) { octave = octave + 1; }
+              initNotes();
+              break;
+            case 3:  // Envelope
+              break;
           }
+        }
         //menuButton(i-12);
       }
     }
@@ -376,18 +411,18 @@ void drawPads(uint16_t keys) {
 }
 
 void drawScope() {
-  int mid = 45; // middle of scope on Y position
-  int height = 20; 
+  int mid = 45;  // middle of scope on Y position
+  int height = 20;
   float maxVal = 0.0f;
   float threshold = 0.002f;
   float scale = 1.0f;
   for (int x = 0; x < 127; x++) {
     int i1 = (synth.scopeIndex + x) & 127;
-    if(synth.scope[i1]>threshold && synth.scope[i1] > maxVal){
+    if (synth.scope[i1] > threshold && synth.scope[i1] > maxVal) {
       maxVal = synth.scope[i1];
     }
   }
-  scale = 1.0f/maxVal;
+  scale = 1.0f / maxVal;
   for (int x = 0; x < 127; x++) {
     int i1 = (synth.scopeIndex + x) & 127;
     int i2 = (i1 + 1) & 127;
@@ -396,8 +431,7 @@ void drawScope() {
       mid - synth.scope[i1] * scale * height,
       x + 1,
       mid - synth.scope[i2] * scale * height,
-      SSD1306_WHITE
-    );
+      SSD1306_WHITE);
   }
 }
 
@@ -414,26 +448,24 @@ void drawVoices() {
 }
 
 void drawVolumebar() {
-  display.fillRect(0,60,(128*VOL), 64, SSD1306_WHITE);
+  display.fillRect(0, 60, (128 * VOL), 64, SSD1306_WHITE);
 }
 // Draws the current Synthesizer sound preset
-void drawInfo(){
+void drawInfo() {
 
   // Show current Sound preset
   display.setTextSize(1);
   display.setTextColor(SSD1306_WHITE);
-  display.setCursor(0,6);
+  display.setCursor(0, 6);
   display.print(sounds[sound]);
 
   // Show current menu mode
-  display.setCursor(64,6);
+  display.setCursor(64, 6);
   display.print("Set:");
-  display.setCursor(100,6);
+  display.setCursor(100, 6);
   display.print(mode_names[mode]);
-  display.setCursor(90,18);
-  display.print("Oct:"+String(octave));
-
-
+  display.setCursor(90, 18);
+  display.print("Oct:" + String(octave));
 }
 
 void updateOLED(uint16_t keys) {
@@ -455,12 +487,12 @@ void setup() {
   for (int i = 0; i < 4; i++) {
     pinMode(X_PINS[i], OUTPUT);
     digitalWrite(X_PINS[i], LOW);
-    pinMode(Y_PINS[i], INPUT); // external pulldowns
+    pinMode(Y_PINS[i], INPUT);  // external pulldowns
   }
 
   // Set up Display
-  Wire.setSDA(4);   // GP4 (pin 6)
-  Wire.setSCL(5);   // GP5 (pin 7)
+  Wire.setSDA(4);  // GP4 (pin 6)
+  Wire.setSCL(5);  // GP5 (pin 7)
   Wire.begin();
   display.begin(SSD1306_SWITCHCAPVCC, OLED_ADDR);
   display.clearDisplay();
@@ -487,7 +519,7 @@ void loop() {
 }
 
 // Seocnd core does inputs + display + leds
-void loop1(){
+void loop1() {
 
   handleInputs();
   if (millis() - lastUI > 30) {