Focusrite ISA One – Classic Transformer Preamplifier with Flexible DI and Optional Digital I/O

ISA One brings legendary ISA-series tone to a rugged desktop package. Featuring a studio-grade mic pre with transformer-based warmth, a flexible front-panel DI input, variable impedance matching, and a dedicated headphone output, it’s ideal for capturing vocals, guitars, or instruments with professional character.

Key Features

• Transformer-coupled mic preamp (Lundahl LL1538): Iconic ISA design delivers rich, open tone with selectable impedance including the classic ISA 110 setting
• Independent DI channel: Front-panel instrument input with high/low impedance, independent gain control, DI output, and amp feed—perfect for direct recording or amp splitting
• Selectably variable impedance: Four mic input impedance choices—Low, ISA 110, Medium, High—letting you shape tone to match any mic
• Insert point before optional A-D conversion: Route hardware processing like EQ or compression into the signal chain before conversion
• Headphone monitoring with cue mix: Integrated headphone output with level control, monitoring either the input or an external cue feed
• Backlit moving-coil VU and LED meters: Visual feedback with adjustable calibration and pre/post-insert monitoring options for precise level control
• Optional ADN2 A-D card: Adds Dante, ADAT, AES3, S/PDIF, and Word Clock connectivity at up to 24-bit/192 kHz—perfect for digital workflows

Customer Benefits

With ISA One, you get authentic ISA-series sonic character in a portable unit—ideal for artists, engineers, and hybrid setups. The independent DI offers flexibility for instruments, while impedance options let you tailor tonal response. The insert point allows seamless analog processing before conversion, and the optional digital I/O card connects you to modern studio networks without sacrificing analog warmth.

Quick Specs

• Inputs: 1 × XLR mic/line, 1 × ¼″ front-panel instrument (DI) with amp output
• Impedance (Mic): Low (600 Ω), ISA 110 (1.4 kΩ), Medium (2.4 kΩ), High (6.8 kΩ)
• Gain (Mic): 0–60 dB stepped, plus 0–20 dB trim
• Gain (Line): –20 to +10 dB stepped, plus 0–20 dB trim
• Instrument Gain: +10 to +40 dB continuously via trim
• Headphone Output: ¼″ with level control, cue mix input
• Metering: VU and dual LED peak meters, pre/post-insert switch, rear-panel calibration
• Power: Internal universal PSU (100–240 V IEC), 35 W consumption
• Dimensions/Weight: Approx. 220 × 290 × 104 mm, 3.9 kg

What’s in the Box

• ISA One desktop mic preamp
• Universal IEC power cable
• Quick-start and safety documentation

Use Cases / Ideal For

Perfect for solo artists, producers, and engineers seeking analog richness on a desktop. Perfect for recording vocals, acoustic instruments, or direct guitar signals—especially when you want tone flexibility and analog processing before digital conversion.

Compatibility

Outputs analog signals to any interface via balanced XLR. Add the optional ADN2 card for seamless integration into Dante, ADAT, AES3, or S/PDIF systems, controlled via network-based RedNet or Dante controllers.

Pros & Cons

✅ Pros:

• Classic transformer-based ISA tone in a compact unit
• Independent DI with impedance control and amp routing
• Analog insert path before optional A-D conversion
• Optional digital card adds future-proof digital connectivity

⚠️ Cons:

• No built-in A-D conversion unless ADN2 is added
• Requires mains power—less mobile than bus-powered units
• Manual settings only—no digital recall or presets

Focusrite ISA One combines timeless analog preamp tone with modern flexibility. Whether in analog-only workflows or bridging to Dante networks, it’s the versatile, tone-first studio companion.