fix pitch analysis

src/App.tsx

@@ -12,8 +12,9 @@ import {
   getFirstPositionNotes,
   getFretboardPositions
 } from './music/Tunings';
-import { Mic, MicOff } from 'lucide-react';
+import { Mic, MicOff, SkipForward } from 'lucide-react';
 import './App.css';
+import './styles/skip-button.css';
 
 const NOTE_MATCH_THRESHOLD_MS = 300; // How long to convert hold note to confirm
 
@@ -149,6 +150,13 @@ function App() {
           )}
 
           {error && <div className="error-message">{error}</div>}
+
+          <div className="action-row" style={{ marginTop: '24px', display: 'flex', justifyContent: 'center' }}>
+            <button className="skip-button" onClick={generateNewNote}>
+              <SkipForward size={18} />
+              Skip Note
+            </button>
+          </div>
         </div>
 
         <div className="pitch-monitor-bar">

src/audio/PitchAnalyzer.ts

@@ -58,9 +58,17 @@ export class PitchAnalyzer {
         }
         rms = Math.sqrt(rms / this.buffer.length);
 
-        if (rms < 0.01) return null; // Silence threshold
+        if (rms < 0.05) return null; // Silence threshold increased to 0.05 for robustness because 0.01 picked up noise
 
         const pitch = this.detector(this.buffer);
+
+        // Guitar range filtering:
+        // Low E (E2) is ~82Hz. Drop D is ~73Hz.
+        // High E (E4) is ~330Hz. 12th fret E5 is ~660Hz.
+        // Harmonics can go higher, but unlikely above 1500Hz for fundamental training.
+        // 19kHz (user reported D#10) is definitely noise.
+        if (pitch && (pitch < 70 || pitch > 1500)) return null;
+
         return pitch;
     }
 }

src/styles/skip-button.css

@@ -0,0 +1,27 @@
+/* App.css additions */
+
+/* Skip Button */
+.skip-button {
+    background: none;
+    border: 2px solid var(--color-text-muted);
+    color: var(--color-text-muted);
+    border-radius: var(--radius-lg);
+    padding: var(--spacing-sm) var(--spacing-md);
+    font-weight: 600;
+    cursor: pointer;
+    transition: all 0.2s ease;
+    display: flex;
+    align-items: center;
+    gap: var(--spacing-xs);
+    font-size: 0.9rem;
+}
+
+.skip-button:hover {
+    border-color: var(--color-text-main);
+    color: var(--color-text-main);
+    background-color: rgba(0, 0, 0, 0.05);
+}
+
+.skip-button:active {
+    transform: scale(0.98);
+}