{"type":"firestarter.listing","listing":{"id":"lst_E5LUa2a3","product_name":"HeartField R1","category":"AMP & DAC","description":"\n\n\nAbout R2R Technology\nFor those seeking precise sound reproduction and authentic analog signal conversion, R2R technology is the ideal choice. R2R DACs convert digital signals into true analog signals through a resistor network. Unlike the widely used Delta-Sigma (Δ-Σ) and 1-bit technologies, which approximate analog signals by modulating digital data into sequences of 0s and 1s, R2R DACs avoid these inherent errors and can accurately reproduce even DC signals.\n\n\nProprietary R2R Architecture\nOur design features 32 ultra-high-precision resistors per channel, totaling 64 resistors, to form a fully discrete R-2R DAC circuit. With 64 resistors each offering a 0.1% tolerance, this uncompromising precision ensures unmatched audio fidelity.\n\n\nMeticulous Sound Tuning\nAt HeartField, we believe the essence of any HiFi product is in its tuning. Advanced technology alone isn't enough—without careful sound craftsmanship, the result is lifeless. Exceptional tuning brings music to life, making every note resonate. HeartField—Experience a world where every note is full of vitality.\n\n\nWide Range of Applications\nAndroid Phones & Tablets: Plug and play, enhancing your audio experience.\niPhone & iPad: Perfect compatibility for high-fidelity sound.\nApple Mac & Windows PC: Seamless connectivity, balancing work and entertainment effortlessly.\nPortable Music Players (with USB Audio Output): Unlock a new level of musical enjoyment.\n\n\nOnly 19.8g Lightweight Design\nIt won’t add extra strain to your cables or USB ports on devices like smartphones. Its near-weightless design ensures easy portability, allowing you to enjoy high-fidelity sound wherever you go.\n\n\n","images":["https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-11.jpg?v=1723797066","https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-04.jpg?v=1723797066","https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-12.jpg?v=1723797066","https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-05.jpg?v=1723797067","https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-07.jpg?v=1723797066","https://cdn.shopify.com/s/files/1/0040/7201/3924/files/1-08.jpg?v=1723797066"],"price":159,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-20T16:26:45.892Z"},"share_url":"https://firestarter.network/l/lst_E5LUa2a3","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_E5LUa2a3' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy HeartField R1' and a budget_max comfortably above $159.00 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."]}}