<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Web Synthesizer</title> <style> /* Stylesheet for the synthesizer */ body { margin: 0; font-family: Arial, sans-serif; background-color: #333; color: #fff; } .synth-container { max-width: 800px; margin: 0 auto; padding: 20px; } h1 { text-align: center; } .controls { display: flex; flex-wrap: wrap; justify-content: space-around; margin-bottom: 20px; } .controls label { margin-right: 10px; } .controls input, .controls select { margin-right: 20px; } .keyboard { display: flex; position: relative; height: 200px; margin: 0 auto; } .key { border: 1px solid #000; border-radius: 5px; } .white { width: 60px; background: #fff; z-index: 1; } .black { width: 40px; background: #000; position: absolute; margin-left: -20px; height: 120px; z-index: 2; } .key:active { background: #ccc; } .key.black:active { background: #555; } /* Positioning keys based on notes */ .key[data-note="C"] { left: 0px; } .key[data-note="C#"] { left: 45px; } .key[data-note="D"] { left: 60px; } .key[data-note="D#"] { left: 105px; } .key[data-note="E"] { left: 120px; } .key[data-note="F"] { left: 180px; } .key[data-note="F#"] { left: 225px; } .key[data-note="G"] { left: 240px; } .key[data-note="G#"] { left: 285px; } .key[data-note="A"] { left: 300px; } .key[data-note="A#"] { left: 345px; } .key[data-note="B"] { left: 360px; } /* Responsive design for smaller screens */ @media (max-width: 600px) { .controls { flex-direction: column; align-items: center; } .keyboard { transform: scale(0.8); } } </style> </head> <body> <div class="synth-container"> <h1>Web Synthesizer</h1> <button id="start-button">Start Synth</button> <div class="controls"> <label for="waveform">Waveform:</label> <select id="waveform"> <option value="sine">Sine</option> <option value="square">Square</option> <option value="sawtooth">Sawtooth</option> <option value="triangle">Triangle</option> </select> <label for="volume">Volume:</label> <input type="range" id="volume" min="0" max="1" step="0.01" value="0.5"> <label for="cutoff">Filter Cutoff:</label> <input type="range" id="cutoff" min="100" max="10000" step="1" value="5000"> <label for="resonance">Filter Resonance:</label> <input type="range" id="resonance" min="0" max="20" step="0.1" value="1"> </div> <div class="keyboard"> <!-- White Keys --> <div class="key white" data-note="C" tabindex="0"></div> <div class="key black" data-note="C#" tabindex="0"></div> <div class="key white" data-note="D" tabindex="0"></div> <div class="key black" data-note="D#" tabindex="0"></div> <div class="key white" data-note="E" tabindex="0"></div> <div class="key white" data-note="F" tabindex="0"></div> <div class="key black" data-note="F#" tabindex="0"></div> <div class="key white" data-note="G" tabindex="0"></div> <div class="key black" data-note="G#" tabindex="0"></div> <div class="key white" data-note="A" tabindex="0"></div> <div class="key black" data-note="A#" tabindex="0"></div> <div class="key white" data-note="B" tabindex="0"></div> </div> </div> <script> /* JavaScript code for the synthesizer functionality */ let audioContext; let masterGain; let filter; let activeNotes = {}; let isAudioInitialized = false; // Map of note frequencies const noteFrequencies = { 'C': 261.63, 'C#': 277.18, 'D': 293.66, 'D#': 311.13, 'E': 329.63, 'F': 349.23, 'F#': 369.99, 'G': 392.00, 'G#': 415.30, 'A': 440.00, 'A#': 466.16, 'B': 493.88 }; // Initialize audio context after user interaction document.getElementById('start-button').addEventListener('click', () => { try { // Use webkitAudioContext for Safari compatibility const AudioContext = window.AudioContext || window.webkitAudioContext; audioContext = new AudioContext(); // Master gain node for volume control masterGain = audioContext.createGain(); masterGain.gain.value = parseFloat(document.getElementById('volume').value); masterGain.connect(audioContext.destination); // Low-pass filter filter = audioContext.createBiquadFilter(); filter.type = 'lowpass'; filter.frequency.value = parseFloat(document.getElementById('cutoff').value); filter.Q.value = parseFloat(document.getElementById('resonance').value); filter.connect(masterGain); // Unlock audio on iOS devices with a short beep const osc = audioContext.createOscillator(); osc.connect(audioContext.destination); osc.start(); osc.stop(audioContext.currentTime + 0.01); isAudioInitialized = true; document.getElementById('start-button').disabled = true; } catch (error) { console.error('Error initializing audio context:', error); } }); // Function to start a note function noteOn(note) { if (!isAudioInitialized) return; if (activeNotes[note]) return; // Prevent duplicate notes try { const osc = audioContext.createOscillator(); const gainNode = audioContext.createGain(); osc.type = document.getElementById('waveform').value; osc.frequency.value = noteFrequencies[note]; // ADSR envelope (attack and release only) const now = audioContext.currentTime; gainNode.gain.setValueAtTime(0, now); gainNode.gain.linearRampToValueAtTime(1, now + 0.1); // Attack gainNode.gain.setValueAtTime(1, now + 0.1); osc.connect(gainNode); gainNode.connect(filter); osc.start(); activeNotes[note] = { osc, gainNode }; } catch (error) { console.error('Error starting note:', error); } } // Function to stop a note function noteOff(note) { if (!activeNotes[note]) return; try { const { osc, gainNode } = activeNotes[note]; const now = audioContext.currentTime; // Release phase gainNode.gain.cancelScheduledValues(now); gainNode.gain.setValueAtTime(gainNode.gain.value, now); gainNode.gain.linearRampToValueAtTime(0, now + 0.5); osc.stop(now + 0.5); // Stop oscillator after release phase setTimeout(() => { osc.disconnect(); gainNode.disconnect(); }, 600); delete activeNotes[note]; } catch (error) { console.error('Error stopping note:', error); } } // Event listeners for keyboard keys const keys = document.querySelectorAll('.key'); keys.forEach(key => { const note = key.getAttribute('data-note'); // Mouse events key.addEventListener('mousedown', () => { noteOn(note); }); key.addEventListener('mouseup', () => { noteOff(note); }); // Touch events for mobile devices key.addEventListener('touchstart', (e) => { e.preventDefault(); noteOn(note); }); key.addEventListener('touchend', (e) => { e.preventDefault(); noteOff(note); }); // Keyboard navigation key.addEventListener('keydown', (e) => { if (e.key === 'Enter' || e.key === ' ') { noteOn(note); } }); key.addEventListener('keyup', (e) => { if (e.key === 'Enter' || e.key === ' ') { noteOff(note); } }); }); // Real-time control updates document.getElementById('waveform').addEventListener('change', () => { // Waveform changes will affect new notes }); document.getElementById('volume').addEventListener('input', (e) => { if (masterGain) { masterGain.gain.setValueAtTime(parseFloat(e.target.value), audioContext.currentTime); } }); document.getElementById('cutoff').addEventListener('input', (e) => { if (filter) { filter.frequency.setValueAtTime(parseFloat(e.target.value), audioContext.currentTime); } }); document.getElementById('resonance').addEventListener('input', (e) => { if (filter) { filter.Q.setValueAtTime(parseFloat(e.target.value), audioContext.currentTime); } }); </script> </body> </html>
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