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Focusrite ISA Two Classic Dual Mono Mic Preamp
Focusrite's ISA Two brings together a totally independent pair of legendary ISA microphone preamps from the original ISA 110 module, combining the best of traditional solid-state electronics with the original input transformer specified by Rupert Neve — the Lundahl LL1538. Two is a nice round number — ideal for recording, say, a vocal and an instrument, or a stereo piano.  If you do need more, the ISA 428 Mk II 4-channel and ISA 828 8-channel units are available as well.
 
When the original ISA 110 was designed, it had a single input impedance that was ideal for the microphones of that era. Today, three more have been added, allowing you to get the very best out of any microphone, vintage or modern. Give a vintage mic the input it expects to get a traditional, warm sound. Pair the ISA Two with modern microphones and get the most transparent sound imaginable. Or experiment and pull out the inner character of any microphone you care to try. Couple that with up to 80dB of gain and you can be ready for anything.
 
In addition to the mic pres, there are front panel instrument inputs for instant access, along with rear-panel line ins. There's also a balanced insert point on the rear panel, actuated with a front-panel button so you can insert the EQ, dynamics or other processors you need. Add to that the user-calibrated 8-LED metering and variable cutoff high-pass filter and you know that with the ISA Two you'll have everything you need to get the highest quality sound into your recordings.
 
Two channels of classic Focusrite mic pres
Focusrite's ISA Two brings together a totally independent pair of classic ISA microphone preamps from the original ISA 110 module, combining the best of traditional solid-state electronics with the original input transformer specified by Rupert Neve – the Lundahl LL1538.
 
Each mic pre has the option of mic, line or the front-panel instrument input, with variable input impedance to ensure you are getting the best performance from the source. Up to 60dB of gain is available on the first four-position rotary and gain range switches, with a further +20dB of continuously variable trim, meaning a huge 80dB of gain is available should it be required. The high-pass filter features variable cut-off frequency between 16 and 420Hz. A pair of 8-segment LED meters show peak signal level in dBFS, while a rear-panel pot allows calibration to suit your A-D converters. Rear-panel insert points allow the use of inline processors such as compression.
 
Now comes with Brainworx bx_console Focusrite plug-in
This awesome plug-in recreates the analog signal paths of Focusrite’s revered ISA 110 and ISA 130 modules, which were a part of the Focusrite Studio Console. Designed and coded by the DSP geniuses at acclaimed software house Brainworx, the new bx_console Focusrite VST/AU/AAX plug-in for Mac and PC faithfully captures the sound, feel and styling of the original iconic hardware.

If you purchased any Red, RedNet or ISA solution from January 2020 on, you will have the plug-in available in your Focusrite account as long as you’ve registered your product.

Focusrite ISA Two Classic Dual Mono Mic Preamp

$899.99Price

  • Lundahl LL1538 mic input transformer

    - Rupert Neve originally chose the Lundahl LL1538 to be the input transformer on the ISA 110. To this day the Lundahl transformer remains the best microphone input transformer available, and is used in every ISA Series mic pre. Rupert Neve also perfected the Zobel network found in the ISA circuit; something which takes a lot of knowledge and a golden set of ears.

    Up to 80 dB of gain

    - ISA Two offers up to 80 dB of clean, distortion-free gain. The much heralded ISA topology also ensures low noise, even at the highest gain levels. The transformer alone supplies 20 dB of gain, while ISA's input stage offers up to 60 dB in addition, giving an astonishing 80 dB of maximum gain on the microphone input.

    Variable input impedance

    - Four choices of input impedance, including the original ISA 110 value, allow you to match the preamp to your microphone, even if it's a vintage type, giving you the best possible sound. The impedance is selected using a switch on the front panel, and the impedance choice is remembered even once the unit is switched off and back on.

    User-calibrated metering

    - Each channel has an eight-LED array to clearly display the level of your two signal. You can line up your analogue levels with your converters of DAW by using the calibration knob on the rear panel. You will be safe in the knowledge that you have avoided clipping on the way in.

    Front panel instrument and rear panel line inputs

    - Two 1/4in. jack sockets on the front panel of ISA Two give you instant access to a transparent DI input. TRS line inputs are available on the rear panel too, and you can step through them instantly to select the one you want.

    Variable cut-off high-pass filter

    - Built in, and easily accessed with its own large knob an illuminated button, is an extremely smooth sounding 18dB/octave high-pass filter of the same design as the original ISA 110 module. This is ideal for cutting out rumble, thumps and other unwanted low-frequency sounds and with a range of 16 to 420 Hz, it's easy to lose what you don't want, and keep what you do.

    Rear panel balanced inserts

    - Each channel of ISA Two has its own balanced insert point. With 1/4in. TRS send and receive connections, your choice of signal processor can be connected and switched in and out using the illuminated switch on the front panel.

  • Mic input response

    Gain Range (Mic)

    - 0 dB to 60 dB in 10 dB steps, plus 0 dB to 20 dB continuously variable trim

    EIN (Mic)

    - Measured at 60 dB of gain with 150 O source impedance and 22 Hz-22 kHz band pass filter -127 dB

    Noise (Mic)

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

    Frequency Response (Mic)

    - At minimum gain (0 dB)-0.5 dB at 10 Hz,?-1 dB at 135 kHz, relative to 1 kHz

    At 60 DB Gain (Mic)

    - -6 dB at 10 Hz, -1 dB at 115 kHz, relative to 1 kHz

    Crosstalk Channel To Channel (Mic)

    - Mic input, with I/P = 0 dBu, gain = 0 dB @ 1 kHz input to channel A, channel B output = -85 dB

    Line input response

    Gain Range (Line)

    - -20 dB to 10 dB in 10 dB steps, plus 0 dB to 20 dB continuously variable trim

    Input Impedance (Line)

    - 10 kO from 10 Hz to 200 kHz

    Frequency Response (Line)

    - At minimum gain (0 dB)-0.3 dB at 10 Hz, -1 dB at 80 kHz, relative to 1 kHz

    Crosstalk Channel To Channel (Line)

    - Line input, with I/P = 0 dBu, gain = 0dB @ 1 kHz input to channel AChannel B output?= -91 dB

    Instrument input response

    Gain Range (Instrument)

    - 10 dB to 40 dB continuously variable trim

    Input Impedance (Instrument)

    - 2 MO

    Noise (Instrument)

    - Measured with 22 Hz-22 kHz band pass filterMinimum gain ( 10 dB) = -95 dBu

    Frequency Response (Instrument)

    - At minimum gain ( 10 dB)-0.1 dB at 10 Hz,?-1 dB at 115 kHz, relative to 1 kHz

    At Maximum Gain ( 40 DB) (Instrument)

    - -2.5 dB at 10 Hz, ?-1 dB at 110 kHz, relative to 1 kHz

    High-pass filter

    Roll-Off

    - 18 dB per octave (3 pole filter)

    Frequency Range

    - Continuously variable from 16 Hz to 420 Hz (-3 dB)

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