🎵 OrchestrAI — Collaborative Music Orchestra Builder Project Plan & Architecture
Concept A web app where musicians upload short audio clips (a guitar riff, a vocal melody, a drum beat), and an AI "conductor" (Claude) analyzes each track, identifies musical properties, suggests what's missing, matches compatible submissions, and arranges them into collaborative compositions — connecting strangers into an orchestra.
Focus Area Creative Flourishing — Amplify human creativity and help people find meaning.
Why This Wins Judging Criteria How We Score Impact Potential Democratizes music collaboration — no studio, no geography, no expensive software. A guitarist in Ithaca + a vocalist in Mumbai = a song. Technical Execution Multi-step agentic Claude pipeline: audio analysis → gap detection → matching → arrangement suggestions. Real Claude API depth, not a wrapper. Ethical Alignment Every contributor is credited. AI conducts but never creates the music — humans stay the artists. Expands access to collaborative creation. Presentation You play the result. Judges hear a combined piece built by strangers during the hackathon. Nothing else in the room competes with that.
Core Features (MVP — Must Ship)
- Track Upload & Profile Upload an audio clip (MP3/WAV, 15-60 seconds) Add metadata: instrument, genre preference, skill level Optional: short text description of what you were going for
- AI Conductor — Track Analysis (Claude API) User uploads a track → backend converts audio to analyzable format Use Web Audio API on frontend to extract: Tempo (BPM) via beat detection Dominant frequency range (maps to instrument register) Duration and waveform shape Send extracted features + user metadata to Claude API Claude returns: Detected key (estimated from metadata + frequency analysis) Mood/energy classification Suggested compatible instruments/parts What's "missing" to make a fuller arrangement
- Composition Matching (Claude API — Agentic) Claude acts as the matchmaker/conductor across all uploaded tracks Agentic loop: Fetch all available tracks and their analysis Identify compatible groups (key, tempo, mood) Suggest arrangements: "Track A (guitar, E minor, 90 BPM) + Track D (vocals, E minor, 88 BPM) + Track F (drums, 90 BPM) could form a composition" Generate arrangement notes: "Layer the guitar as foundation, bring vocals in at 0:08, drums throughout" This is the agentic core — Claude reasons across multiple tracks autonomously
- Composition View & Playback Visual timeline showing layered tracks (like a simple DAW) Play tracks simultaneously using Web Audio API Adjust individual track volume Show each contributor's name and instrument
- Community Feed Browse completed compositions See contributor credits "Join this composition" — if a piece needs a bass line, you can record and submit one
Stretch Features (If Time Allows) Live recording via browser microphone (MediaRecorder API) Voting/reactions on compositions Claude arrangement notes displayed as a "conductor's commentary" explaining why the tracks work together Export — download the mixed composition as a single audio file AI-suggested prompts — "This composition needs a mellow bass line in C major at 72 BPM. Can you contribute?"
Tech Stack Frontend React (Vite for fast setup) Tailwind CSS for styling Web Audio API for playback, waveform visualization, and basic audio analysis Wavesurfer.js (open source) for waveform display in the timeline view Backend Node.js + Express (fast to scaffold) Claude API (claude-sonnet-4-20250514) for track analysis, matching, and arrangement Multer for file upload handling File-based storage (JSON + uploaded audio files on disk) — no database needed for a hackathon Audio Processing Web Audio API (browser-side) for tempo detection, frequency analysis, waveform extraction Send extracted features as structured data to Claude (not raw audio) Tone.js (optional) for more advanced audio manipulation if needed
Architecture Diagram ┌─────────────────────────────────────────────┐ │ Frontend │ │ (Next.js) │ │ │ │ ┌──────────┐ ┌──────────┐ ┌─────────────┐ │ │ │ Upload │ │ Composition│ │ Community │ │ │ │ + Record │ │ Timeline │ │ Feed │ │ │ └────┬─────┘ └─────┬────┘ └──────┬──────┘ │ │ │ │ │ │ │ ┌────┴──────────────┴─────────────┴──────┐ │ │ │ Web Audio API Layer │ │ │ │ (analysis, playback, visualization) │ │ │ └────────────────┬───────────────────────┘ │ └───────────────────┼─────────────────────────┘ │ HTTP / REST ┌───────────────────┼─────────────────────────┐ │ │ Backend │ │ (Node + Express) │ │ │ │ ┌────────────┐ ┌────────────────────────┐ │ │ │ Upload │ │ Claude API Service │ │ │ │ Handler │ │ │ │ │ │ (Multer) │ │ ┌──────────────────┐ │ │ │ └─────┬──────┘ │ │ Track Analyzer │ │ │ │ │ │ │ (single track) │ │ │ │ ▼ │ ├──────────────────┤ │ │ │ ┌───────────┐ │ │ Conductor Agent │ │ │ │ │ File │ │ │ (multi-track │ │ │ │ │ Storage │ │ │ matching + │ │ │ │ │ (JSON + │ │ │ arrangement) │ │ │ │ │ audio) │ │ └──────────────────┘ │ │ │ └───────────┘ └────────────────────────┘ │ └─────────────────────────────────────────────┘
Claude API Usage (Key Selling Point) Call 1: Track Analysis System: You are a music theory expert and orchestral conductor. Analyze this audio track based on the following extracted features and user-provided metadata.
User: { instrument: "acoustic guitar", genre: "indie folk", bpm_detected: 92, dominant_freq_range: "200-800Hz", duration: "32s", user_description: "melancholy fingerpicking pattern" }
→ Claude returns: key estimation, mood, energy level, compatible instruments, arrangement suggestions
Call 2: Conductor Agent (Agentic Multi-Step) System: You are an orchestral conductor building compositions from individual musician submissions. Analyze all available tracks and create optimal groupings.
Step 1: Review all track analyses Step 2: Identify compatible groups by key, tempo, mood Step 3: For each group, create arrangement instructions Step 4: Identify gaps — what instrument/part would complete each composition?
→ Claude returns: composition groupings, arrangement notes, "help wanted" prompts for missing parts
Team Task Division (4 people) Person 1 — Frontend: Upload & Recording File upload component with drag-and-drop Browser audio recording (stretch goal) Waveform visualization for uploaded tracks Track metadata form Person 2 — Frontend: Composition View & Feed Multi-track timeline component (layered waveforms) Playback controls with per-track volume Community feed showing all compositions Contributor credit display Person 3 — Backend: API & File Handling Express server setup with routes File upload handling (Multer) Audio feature extraction pipeline (or receive from frontend) JSON-based data storage for tracks and compositions Serve audio files for playback Person 4 — Backend: Claude Integration & Agent Logic Claude API integration for track analysis Conductor agent: multi-step matching and arrangement logic Prompt engineering and testing "Gap detection" — what instruments are needed Generate conductor commentary for compositions
API Routes POST /api/tracks/upload — Upload audio + metadata GET /api/tracks — List all tracks GET /api/tracks/:id — Get single track + analysis POST /api/tracks/:id/analyze — Trigger Claude analysis
POST /api/compositions/generate — Run conductor agent GET /api/compositions — List all compositions GET /api/compositions/:id — Get composition details POST /api/compositions/:id/add — Add a track to a composition
Data Models Track { "id": "uuid", "musician_name": "string", "instrument": "string", "genre": "string", "file_path": "string", "duration_seconds": 32, "bpm": 92, “Piece_name”:”string”, #If piece name match by piece name if original piece use analysis to match "analysis": { "estimated_key": "E minor", "mood": "melancholy", "energy": "low-medium", "compatible_instruments": ["cello", "soft vocals", "light percussion"], "arrangement_notes": "Works as a foundation track. Fingerpicking pattern leaves space for a vocal melody in the upper register." }, "created_at": "timestamp" }
Composition { "id": "uuid", "title": "Generated or user-given title", "tracks": ["track_id_1", "track_id_2", "track_id_3"], "conductor_notes": "Claude's arrangement commentary", "missing_parts": ["bass line", "harmony vocals"], "help_wanted_prompt": "This composition needs a warm bass line in E minor around 90 BPM to ground the arrangement.", "created_at": "timestamp" }
Demo Script (3-Minute Presentation) 0:00–0:30 — "Musicians everywhere create alone. OrchestrAI connects them." Show the problem. 0:30–1:15 — Live upload a guitar track. Show Claude analyzing it in real time. Display the analysis: key, mood, what it needs. 1:15–2:00 — Show the conductor agent matching it with 2-3 other tracks uploaded during the hackathon. Display the arrangement notes. 2:00–2:30 — Hit play. The combined composition plays. Judges hear the result. 2:30–3:00 — Show the "help wanted" feature: "This piece needs a bass line. Can you contribute?" Zoom out on the vision — a global orchestra built by strangers. Key Risks & Mitigations Risk Mitigation Audio analysis accuracy Don't try to do perfect key detection — use user-provided metadata + Claude's reasoning. Be honest about estimation in the UI. Tracks don't sound good together Pre-seed with 3-4 compatible sample tracks. Claude's arrangement notes help set expectations. Time crunch Prioritize: upload → analysis → playback of 2+ tracks together. Everything else is polish. Claude API rate limits Cache analysis results. Don't re-analyze on every page load.