{"type":"firestarter.listing","listing":{"id":"lst_qXJhwq82","product_name":"Cayin YB04 in-Ear Monitor with Four Balanced Armature Drivers Earphone","category":"Earphone","description":"Technical Specifications:-\n\n>Four Balanced Armature Driver Unit\n\n>Impedance: 30 Ohms\n\n>Frequency Response Range: 18Hz-40kHz\n\n>Sensitivity: 113dB\n\n>0.78mm Two-Pin connector type\n\n>Machined CNC Aviation Aluminium Alloy\n\n>Crystallized OFC Silver Alloy Cable with 3.5mm Termination Plug\n\nCayin is a China-based brand which manufactures premium-grade audio products, they have products widely famous among the audiophiles all around the globe. Quite recently they announced their multi-driver pair of in-ear monitors, the Cayin YB04. It has four balanced armature driver units on each side with two Knowles armatures and two Sonion armature drivers working together in a beautiful CNC aviation-grade aluminum alloy shells.\n\nFour Drivers On Each Side:-\n\nThe Cayin YB04 is equipped with four different balanced armature units on each side, there are two Knowles balanced armature driver units which acts as tweeters and two Sonion balanced armature units which act as woofer units. The drivers collectively generate a crisp and clear sound output with precise details and a wider soundstage. The sound output is very relaxing and soothing with no harshness at all.\n\nAviation-Grade CNC Alloy Earpiece Shells:-\n\nThe Cayin YB04 earpieces are made up of aviation-grade machined alloy, this provides the earpieces a solid, robust build quality in a jointless structure with matt black finish. The jointless structures reduce resonance and rippling effects between the driver units, providing its users a pure natural sound output. The shells have extremely strong aluminum ear nozzles with dust filters.\n\nThe shells are designed with custom-developed housing with months of research to give the users a perfect fit with proper isolation.\n\nNeutral and Balanced Sound Output:-\n\nThe Cayin YB04 is tuned with such precision that it provides its users with a balanced and neutral sound output, with amazing clarity, the bass thumps are deep and thumpy, the mids sound natural with great acoustic ","images":["https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-907250.jpg?v=1573285130","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-600023.jpg?v=1573285130","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-422528.jpg?v=1573285130","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-428681.jpg?v=1573285130","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-724218.jpg?v=1573285130","https://cdn.shopify.com/s/files/1/0031/0453/8673/products/cayin-yb04-in-ear-monitor-with-four-balanced-armature-drivers-earphone-hifigo-559715.jpg?v=1573285130"],"price":499,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-20T16:26:31.815Z"},"share_url":"https://firestarter.network/l/lst_qXJhwq82","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_qXJhwq82' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Cayin YB04 in-Ear Monitor with Four Balanced Armature Drivers Earphone' and a budget_max comfortably above $499.00 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."]}}