{"type":"firestarter.listing","listing":{"id":"lst_Fj_4CdRz","product_name":"xDuoo MT-603 Multichoice Pre-amp","category":"Headphone Amp (Tube)","description":"An Airport For Your Aux Cables\nIf you’re swimming in aux cables from all of your analog devices, you’re going to love the xDuoo MT-603. Connect all of your analog sources for fast and convenient switching, while enjoying the benefits of tube amplification. \n3 RCA input ports\nConnect a turntable, CD player, cassette player, radio, or other RCA-equipped unit into one of the MT-603’s four RCA inputs and then run them to a single amp. \nWarm tube pre-amplification\nThere are many benefits to tube pre-amplification, like boosting a weak signal before it reaches your amplifier or adding the warm tube sound to a solid state amplifier. The MT-603 uses a nine-pin 12AU7 vacuum tube. A classic of the tube world, the 12AU7 is easily replaced and rolled. \nToneluck switches\nChunk. Clunk. Is there anything more satisfying than analog switches? Enjoy highly-durable, highly-satisfying switching with the MT-603’s TONELUCK switches. \nAluminum alloy shell\nThere’s more than meets the eye with this pre-amp. A sandblasted aluminum alloy shell is a delight to operate, providing long-lasting protection and style. \nProduct highlights\n\n3 RCA inputs\nSweet tube sound\nTONELUCK analog switches\nProfessional capacitors\nGold-plated RCA ports\nAluminum alloy shell\n\nSpecs\n\nInputs: RCA x3, 3.5mm x1\nOutputs: RCA x1\nTube: 12AU7\nPower supply: DC12V/2A\nFrequency response: 10Hz - 40kHz (±0.5dB)\nTHD+N: ≤0.01%\nSNR: 100dB\nGain: 0dB\nSize: 4.7 x 3 x 1.5” (12 x 7.8 x 4cm)\nWeight: 0.79lbs (0.36kg)\n","images":["https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454766768299.jpg?v=1628025397","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454455275691.jpg?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29495495557291.jpg?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454451605675.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454451638443.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454451277995.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454677115051.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29529645482155.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454451114155.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29454451081387.gif?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29495709171883.jpg?v=1740279308","https://cdn.shopify.com/s/files/1/0225/2721/3642/products/apos-audio-xduoo-headphone-amp-tube-xduoo-mt-603-multichoice-pre-amp-29529538068651.jpg?v=1740279308"],"price":109,"currency":"USD","in_stock":true,"inventory_qty":29997,"dynamic_pricing":false,"listed_at":"2026-06-20T16:26:00.720Z"},"share_url":"https://firestarter.network/l/lst_Fj_4CdRz","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 <your Firestarter API key>","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_Fj_4CdRz' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy xDuoo MT-603 Multichoice Pre-amp' and a budget_max comfortably above $109.00 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."]}}