Focusrite ISA Two Dual Channel Classic ISA Mic Preamp/DI

Focusrite ISA Two Dual Channel Classic ISA Mic Preamp/DI

With variable impedance the transformer-based microphone inputs are featured in the Focusrite ISA Two which is a dual mono microphone preamp. Based on the designs of Focusrite Forte and studio consoles, the preamplifiers offer up to 80 db of gain, whereas two front panel instrument inputs permit for immediate access.

You can get a pair of LL1538 transformers with a 3-section winding featured in the microphone inputs. It leads a very low leakage inductance, along with an extended frequency response.

Each is encapsulated in mu-metal cans, to resist them from stray magnetism. Each channel is having fully-balanced insert point, activated using a front-panel button, making it simple to insert a choice of outboard EQ, a compressor, or limiter.

Gain

• Offers up to 80 dB of clean, distortion-free gain
• ISA topology ensures low-noise even at the highest gain levels
• The transformer supplies 20 dB of gain, while the ISA's input stage offers up to 60 dB of additional gain on the microphone input 

Variable Input Impedance

• Four choices of input impedance, including the original ISA 110 value, allow for matching the preamp to a different microphones, even a vintage type, for the best possible sound
• Impedance is selected using a switch on the front panel
• Impedance choice is remembered even when the unit is switched off and back on

Instrument and Line Inputs

• Two 1/4" TS connectors on the front panel provide access to a transparent DI input 
• TRS line inputs are available on the rear panel and a front panel switch allows for stepping through them to instantly select required input

Focusrite ISA Two Specs

• Number of Channels: 2
• Multi Function: No
• Inputs: 2 x 1/4" TS phone Instrument (front panel) 2 x XLR Microphone (rear panel) 2 x 1/4" TRS phone Line (rear panel) 2 x 1/4" TRS phone Return (rear panel)
• Input Impedance: Mic (@ 1 kHz): Low = 600Ω, ISA 110 = 1.4Ω, Medium = 2.4Ω, High = 6.8 kΩ Line: 10 kΩ from 10 Hz to 200 kHz Instrument: >2 MΩ
• Maximum Input Level: Mic: +7 dBu with a THD+N <0.7% at 1 kHz measured at 0 dB of gain with 150Ω source impedance and 22 Hz to 22 kHz band-pass filter
• Outputs: 2 x XLR 2 x 1/4" TRS phone Send
• Maximum Output Level: +24 dBu with a THD+N <0.01% at 1 kHz measured with 150Ω source impedance and 22 Hz to 22 kHz band-pass filter
• Phantom Power: +48V, individually switchable
• Gain Range: Mic: 0 dB to +60 dB in 10 dB steps, plus 0 dB to +20 dB continuously variable trim Line: -20 dB to +10 dB in 10 dB steps, plus 0 dB to +20 dB continuously variable trim Instrument: +10 dB to +40 dB continuously variable trim
• Frequency Response: Mic @ minimum gain (0 dB): 10 Hz to 135 kHz, -0.5/1 dB Mic @ +60 dB gain: 10 Hz to 115 kHz, -6/-1 dB Line @ unity gain (0 dB): 10 Hz to 80 Hz, -0.3/-1 dB Instrument @ minimum gain (+10 dB): 10 Hz to 115 kHz, -0.1/1 dB Instrument @ maximum gain (+40 dB): 10 Hz to 110 kHz, -2.5/1 dB
• EIN: -127 dB (60 dB of gain with 150Ω source impedance and 22 Hz to 22 kHz band-pass filter)
• Noise: Mic: -97 dBu @ output with unity gain (0 dB) and 22 Hz to 22 kHz band-pass filter Line: -97 dBu @ output with unity gain (0 dB), measured with 50Ω source impedance and 22 Hz to 22 kHz band-pass filter Instrument: -95 dBu, minimum gain (+10 dB) with 22 Hz to 22 kHz band-pass filter
• Signal to Noise Ratio: Mic: 121 dB, with +24 dB maximum output (150Ω source impedance and 22 Hz to 22 kHz band-pass filter) Line: 121 dB, with +24 dB maximum output (50Ω source impedance and 22 Hz to 22 kHz band-pass filter)
• THD + N: Mic: <0.0007% @ 1 kHz (-20 dBu input signal with +30 dB gain and 22 Hz to 22 kHz band-pass filter) Line: <0.002% @ 1 kHz (0 dBu input signal with +10 dB gain and 22 Hz to 22 kHz band-pass filter)
• CMRR: Mic Input @ 60 Hz: -94 dB, with +24 dBu maximum output Mic Input @ 10 kHz: -91 dB, with +24 dBu maximum output
• Crosstalk: Mic: -85 dB (I/P = 0 dBu, gain = 0 dB @ 1 kHz input to channel A, channel B output) Line: -91 dB (I/P = 0 dBu, gain = 0dB @ 1 kHz input to channel A, channel B output)
• Power Requirements: 100~240 VAC, 50/60 Hz
• Dimensions (WxDxH): 19 x 11 x 1.7" (480 x 280 x 44 mm)
• Weight: 8.2 lb (3.7 kg)
• Specialties: 18 dB per octave (3-pole) high-pass filter, continuously variable from 16 Hz to 420 Hz (-3 dB)

Packaging Info

• Package Weight: 12 lb
• Box Dimensions (LxWxH): 25.8 x 14.8 x 5.2"