{"type":"firestarter.listing","listing":{"id":"lst_mRdy2xtI","product_name":"Knight School Filter (Built Pedal)","category":"Effects","description":"NOT A DIY KIT. THIS IS A FULLY BUILT PEDAL. \nIf you’ve ever heard a synthesizer in action, chances are you’ve heard of a low-pass filter, a powerful tone-sculpting tool whose nuts and bolts increase exponentially as utility increases linearly. Found on even the earliest examples of analog synthesis, the low-pass filter establishes a cutoff frequency, and then rejects all frequencies above it at an intensity determined by the filter’s construction. We’ve taken that guesswork out of the picture, letting you define your own cutoff frequency with an aggressive filter design. A resonance control lets you dial in the amount of “synthiness” by feeding the output signal back into the front end. A gain control dials in some grit on the front end to drive the filter harder. This filter design absolutely excels when stacked behind your favorite dirt or mod pedal; a hotter signal gets completely swallowed by the filter for even more synth-like textures. Try a fuzz in front for some serious Zappa tones!\nOur Filter kit puts this synth-like control right at your feet, giving you a Resonance control (also known as “feedback”) for a more intense filtering experience, as well as an onboard Gain control to add some grit to the signal. This kit sounds absolutely dynamite when stacked with your favorite dirt box. You’re going to love this one.\n","images":["https://cdn.shopify.com/s/files/1/0370/1873/0628/files/ks-filter-shopify-01-min.png?v=1723885983"],"price":134.99,"currency":"USD","in_stock":true,"inventory_qty":9999,"dynamic_pricing":false,"listed_at":"2026-06-20T16:26:04.155Z"},"share_url":"https://firestarter.network/l/lst_mRdy2xtI","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_mRdy2xtI' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Knight School Filter (Built Pedal)' and a budget_max comfortably above $134.99 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."]}}