Focusrite Dual Mono Microphone Preamp
Product Highlights:
- Dual Mono
- Transformer Based Microphone Inputs
- Variable Input Impedance
- Front Panel Instrument Inputs
- Focusrite ISA Two - Microphone Preamp
- AC Power Cable
- Limited 3-Year Warranty
Focusrite Dual Mono Microphone Preamp
Focusrite ISA-2 Dual Mono Microphone Preamp
The ISA Two from Focusrite is a dual mono microphone preamp featuring transformer based microphone inputs with variable input impedance. Based on the legendary designs found in the Focusrite Forte and Studio consoles, the preamps provides up to 80 dB of gain, while two front panel instrument inputs allow for immediate access to two transparent DIs.
The microphone inputs feature a pair of Lundahl LL1538 transformers with a 3-section winding that results in very low leakage inductance, along with an extended frequency response. To shield them from stray magnetism, each is encapsulated in mu-metal cans. Each channel has a fully-balanced insert point, activated using a front-panel button, making it easy to insert a choice of outboard EQ, a compressor, or limiter.
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) |