Focusrite ISA One

Classic Mic Pre With Independent DI

Featuring a rugged, portable all-metal enclosure, ISA One combines the classic Focusrite microphone preamp with a flexible, independent DI channel and optional 192kHz precision A-D conversion. At the heart of the ISA range is the microphone preamplifier with its Lundahl input transformer – essentially the same circuit, based on the original ISA 110, that has been used for 30 years in successive Focusrite designs. The input transformer imparts a special character to the sound that can't be truly emulated in any other way, while the modern twist of variable input impedance allows for a new degree of flexibility.

Whether you're an artist, engineer or producer, you'll appreciate the versatility of the ISA One, with its front-panel DI input. The DI includes low/high impedance switching and an amplifier output, and its own feed to the optional A-D converter and separate rear-panel XLR output.

• Classic ISA mic preamp design featuring Lundahl LL1538 input transformer
• Flexible independent DI channel
• Switchable input impedance including classic ISA 110 setting
• Headphone output with volume control
• Dedicated insert point
• Optional stereo 192kHz A-D conversion card

SPECIFICATIONS

MIC INPUT RESPONSE

Gain Range (Mic): 0dB to 60dB in 10dB steps 20 dB of variable gain

EIN (Mic): -126dB measured at 60dB of gain with 150 Ohm terminating impedance and 22Hz/22kHz band-pass filter

Noise (Mic): Noise at output with unity gain (0 dB) and 22 Hz-22 kHz band pass filter-97 dBu

Signal-To-Noise Ratio (Mic): 106 dB relative to max headroom (9dBu)

Frequency Response (Mic): At minimum gain (0 dB)-0.5dB down at 10Hz and -3dB down at 125kHz

CMRR (Mic): 98dB (Channel 1, 1kHz, maximum gain with 24 dBu input)

Crosstalk Channel To Channel (Mic): With 10dB@1kHz input to chA, chB output =104dBrA. With 10dB@10kHz input to chA, chB output = 84dBrA

LINE INPUT RESPONSE

Gain Range (Line): -20dB to 10dB in 10dB steps 20 dB of variable gain

Input Impedance (Line): 10 kO from 10 Hz to 200 kHz

Total Harmonic Distortion Noise (Line): Measured with a 0 dBu input signal, and a 22 Hz-22 kHz band pass filter0.0001

Frequency Response (Line): At unity gain (0 dB)-0.3dB down at 10Hz and -3dB down at 200kHz

INSTRUMENT INPUT RESPONSE

Gain Range (Instrument): 10dB to 40dB continuously variable

Input Impedance (Instrument): High = greater than 1M Low =greater than 300k

THD (Instrument): At minimum gain ( 10)

HIGH-PASS FILTER

Roll-Off: 18 dB per octave (3 pole filter)

Frequency: Fixed 75Hz measured at the 3dB down point

WEIGHT AND DIMENSIONS

W X D X H: 220mm (W) x 104mm (H) x 254 - 290mm

Weight: 3.9 kg (8.6 lbs)