{"type":"firestarter.listing","listing":{"id":"lst_x-m2u-Qe","product_name":"LADDER Bach II Audio Preamplifier","category":"Headphone Amp","description":" \nFully-balanced, Class-A preamplifier\nThe Bach II is a fully-discrete, pure Class A, fully-balanced preamplifier built for systems that need clean switching, precise volume control, and flexible I/O. You get two balanced XLR inputs plus a high-level RCA input, then both XLR and RCA outputs for feeding power amps or active speakers. A 60-step relay attenuator keeps channel balance locked in, plus global voltage power and remote control for daily use.\nBalanced connectivity for real-world systems\nThe Bach II gives you 2 XLR balanced inputs and 1 high-level RCA input, plus outputs on both XLR and RCA. Balanced lines help reject noise over longer cable runs.\nPure Class A, fully discrete signal stage\nThis is a Class-A, fully-discrete design with a fully-balanced output circuit. Class A means the output devices stay conducting rather than switching on and off, which is one less variable in the signal path. The balanced architecture focuses on low noise and strong channel separation, which is useful when you listen at lower levels and still want space and placement to hold steady.\n60-step relay attenuator volume control\nThe Volume is handled by a microprocessor-controlled relay step attenuator with precision-matched resistors. The benefit here isn’t “more steps” but repeatability and channel matching. Left and right stay aligned as you turn the knob, so the center images stay centered and small level changes don’t skew the stage left or right.\nPower filtering that keeps the background quiet\nInside, an 80W toroidal transformer feeds a low-noise linear supply with a capacitor bank and layered filtering using ELNA electrolytic capacitors and WIMA capacitors. In practice, background noise is controlled, so quiet passages don’t get smudged by power-related issues. \nMinimal controls that stay out of your way\nTwo large knobs handle what you need most: power/source/mute on one side, volume on the other. Laser-engraved labeling is meant to stay readable long-term. The front display","images":["https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393184.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393182.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393194.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393193.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393192.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393191.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393190.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393189.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393188.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393187.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393186.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393185.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393183.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393197.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393196.jpg?v=1774441230","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ladder-headphone-amp-ladder-bach-ii-audio-preamplifier-1214393195.jpg?v=1774441230"],"price":945,"currency":"USD","in_stock":true,"inventory_qty":19998,"dynamic_pricing":false,"listed_at":"2026-06-20T16:25:56.684Z"},"share_url":"https://firestarter.network/l/lst_x-m2u-Qe","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_x-m2u-Qe' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy LADDER Bach II Audio Preamplifier' and a budget_max comfortably above $945.00 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."]}}