{"product_id":"focusrite-isa-428-mkii","title":"Focusrite ISA 428 mkII","description":"\u003cdiv lang=\"en\"\u003e\n\u003cp\u003e\u003cstrong\u003eFocusrite ISA 428 MkII\u003c\/strong\u003e — a 4-channel microphone preamp built around Lundahl LL1538 transformers, based on the classic ISA 110 design from Focusrite's 1980s consoles.\u003c\/p\u003e\n\n\u003cp\u003eBuilt for studios chasing the transparent yet transformer-colored sound of the consoles designed for George Martin's AIR Studios. ISA 428 MkII carries a circuit topology unchanged for decades into a convenient 2U enclosure, adding switchable input impedance and optional digital conversion, making it equally useful as a standalone analog front end or paired with any digital interface.\u003c\/p\u003e\n\n\u003ch3\u003eMatching Impedance to the Microphone's Character\u003c\/h3\u003e\n\u003cp\u003eThe original ISA preamp was designed around microphones available in the 1980s, limiting its versatility with modern capsules carrying different impedance characteristics. ISA 428 MkII solves this by adding three extra input impedance settings alongside the classic Vintage ISA 110 mode, letting an engineer deliberately choose the tonal character — from transformer-core warmth and saturation to clean, transparent signal transfer — depending on the microphone model and source material.\u003c\/p\u003e\n\n\u003ch3\u003eExpanding to a Full Digital Front End Without New Hardware\u003c\/h3\u003e\n\u003cp\u003eStudios bridging an analog preamp chain with a digital workflow need a flexible conversion path that doesn't force a separate converter purchase. The optional eight-channel A-D card fitted inside the ISA 428 MkII converts the signal with 122dB of dynamic range and jitter performance below 250 picoseconds, output over a D-Sub25 connector that interfaces directly with Pro Tools HD and other digital gear. That means a single 2U unit works as a purely analog preamp or a complete digital front end, whichever the session calls for.\u003c\/p\u003e\n\n\u003ch3\u003eKEY FEATURES\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e4 channels of microphone preamp based on the original ISA 110 design\u003c\/li\u003e\n\u003cli\u003eLundahl LL1538 input transformer with a custom Zobel network\u003c\/li\u003e\n\u003cli\u003eSwitchable input impedance, including the classic Vintage ISA 110 mode\u003c\/li\u003e\n\u003cli\u003eGain up to +60dB in 10dB steps, plus continuously variable +20dB (up to 80dB total)\u003c\/li\u003e\n\u003cli\u003e4 front-panel instrument inputs (no separate DI box needed)\u003c\/li\u003e\n\u003cli\u003e4 line inputs and switchable insert points on every channel\u003c\/li\u003e\n\u003cli\u003eVariable high-pass filter on every channel\u003c\/li\u003e\n\u003cli\u003e6-segment LED metering for accurate level monitoring\u003c\/li\u003e\n\u003cli\u003eOptional eight-channel A-D card (122dB dynamic range, jitter below 250ps)\u003c\/li\u003e\n\u003cli\u003eIncludes the Brainworx bx_console Focusrite SC plugin\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTECHNICAL SPECIFICATIONS\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eChannel count: 4\u003c\/li\u003e\n\u003cli\u003eFrequency response (0dB gain, mic): -0.35dB at 20Hz, -3dB at 122kHz\u003c\/li\u003e\n\u003cli\u003eFrequency response (60dB gain, mic): -2.5dB at 20Hz, -3dB at 103kHz\u003c\/li\u003e\n\u003cli\u003eGain range: 0 to +60dB in 10dB steps, plus 0 to +20dB continuously variable (up to 80dB total)\u003c\/li\u003e\n\u003cli\u003eInput transformer: Lundahl LL1538\u003c\/li\u003e\n\u003cli\u003eInputs: mic, line, instrument (front panel)\u003c\/li\u003e\n\u003cli\u003eInput impedance: switchable, 4 settings including Vintage ISA 110\u003c\/li\u003e\n\u003cli\u003eOptional A-D card: 8 channels, 122dB dynamic range, jitter below 250ps, D-Sub25 connector\u003c\/li\u003e\n\u003cli\u003eChassis format: 2U rack\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e","brand":"Focusrite","offers":[{"title":"Default Title","offer_id":54339141206353,"sku":"52282","price":1897.35,"currency_code":"EUR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/8741\/0769\/files\/FocusriteISA428mkII1.jpg?v=1784735387","url":"https:\/\/wrdtunes.com\/products\/focusrite-isa-428-mkii","provider":"Wired Tunes","version":"1.0","type":"link"}