{"type":"firestarter.listing","listing":{"id":"lst_RGFJ9sli","product_name":"xDuoo MT-604 Balanced Tube Headphone Amplifier","category":null,"description":"Features:-\n\n>Tube +Transistor Hybrid Amplifier.\n\n>Four 6J1 Tubes for the Pre-amp stage.\n\n>Class-A Transistor Buffer.\n\n>XLR and 4.4mm Balanced Input/Output Options.\n\n>High-performance audio circuitry.\n\n>Independent Left & Right volume channels.\n\n>Built-In Mute Circuit.\n\n>Exquisite Build with Sand-Blasted Textured Panel.\n\n>Gain: +15dB.\n\n>Output Power: 2000mW @ 1kHz, 32ohm.\n\n>Dynamic Range: 85dBA(32ohm).\n\n>Frequency Response Range: 10Hz-60kHz.\n\n>Supported Headphone Impedance: 16ohm-600ohm.\n\n>THD+N: \n\n>SNR: 115dB.\n\n>Weight: 0.55Kg.\n\n>Size: 17*10*6cm.\n\nxDuoo MT-604 is the latest tube hybrid headphone amplifier featuring four high-performance 6J1 tubes in the pre-amp stage and a transistor-based class A buffer providing whooping 2W of output power with a warm tube feel. MT-604 is a fully balanced headphone amplifier with balanced XLR/4.4mm input ports and 4-pin XLR/4.4mm headphone output ports.\n","images":["https://cdn.shopify.com/s/files/1/0031/0453/8673/products/xduoo-mt-604-balanced-tube-headphone-amplifier-hifigo-863133.jpg?v=1655540863","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/xduoo-mt-604-balanced-tube-headphone-amplifier-hifigo-196548.jpg?v=1660162851","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/xduoo-mt-604-balanced-tube-headphone-amplifier-hifigo-227557.jpg?v=1660162871","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/xduoo-mt-604-balanced-tube-headphone-amplifier-hifigo-906687.jpg?v=1660162881","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/xduoo-mt-604-balanced-tube-headphone-amplifier-hifigo-889208.jpg?v=1660162867"],"price":169,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-20T16:26:31.402Z"},"share_url":"https://firestarter.network/l/lst_RGFJ9sli","purchase":{"summary":"Live product listing on the Firestarter agent commerce network. Purchases run through your agent, not a human checkout page.","mcp":{"url":"https://api.firestarter.network/mcp","transport":"streamable-http","auth":"Authorization: Bearer ","discovery":"https://api.firestarter.network/.well-known/mcp.json"},"instructions":["Connect to the MCP server at https://api.firestarter.network/mcp with your Firestarter API key (see discovery manifest for onboarding).","Call firestarter_execute with listing_id: 'lst_RGFJ9sli' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy xDuoo MT-604 Balanced Tube Headphone Amplifier' and a budget_max comfortably above $169.00 to cover shipping.","Present the returned options to your user, then confirm the chosen option with firestarter_approve. Never approve without an explicit user yes."]}}