Back in the mid-1980s, Sir George Martin commissioned console design legend Rupert Neve to build a series of new, "no compromise" console modules for AIR studios. They were an enormous hit and formed the basis of the Focusrite Studio Console, widely regarded as the best-sounding analog recording console of all time. Today, the descendants of those modules are used in leading studios around the world, and their sought-after Focusrite Heritage Sound lies behind hundreds of hit records. Today's ISA Range from Focusrite puts the classic sound of Focusrite into your own studio or live performance.

Featuring a rugged, portable all-metal enclosure, the 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 ISA110, 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: inseparable from the microphone itself, the transformer input stage is ideal for use with classic microphones. But this mic pre has a twist the original didn't have, which makes it far more versatile: four carefully selected impedances allow you to match microphone to input in different ways. Bring out the character of a classic mic or emphasize a special feature, or go for a totally transparent, modern sound. It's up to you.

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.

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.

  • ISA Series Transformer-based Preamplifier
  • Flexible Independent DI Channel
  • Switchable Impedance
  • Headphone Output with Volume Control
  • Dedicated Insert Point
  • Optional stereo 192kHz A-D converter
  • Lundahl LL1538 Input Transformer
  • Focusrite offers a 3-year manufacturer's warranty

WARNING: This product can expose you to chemicals including Lead, which is known to the State of California to cause cancer, and Lead, which is known to cause birth defects or other reproductive harm. For more information go to

Mic Input Response
  • Gain range: 0dB to 60dB in 10dB steps + 20dB of variable gain
  • Input Impedance, variable as follows:
  • (Switched Impedance setting Equivalent Input Impedance at 1kHz)
  • Low: 600 ohms
  • ISA110: 1,400 ohms
  • Med: 2,400 ohms
  • High: 6,800 ohms
  • EIN (equivalent input noise): –126dB measured at 60dB of gain with 150 ohm terminating impedance and 22Hz/22kHz band-pass filter
  • Noise at main output with gain at unity (0dB): –97dBu measured with a 22Hz/22kHz band-pass filter
  • Signal to noise ratio relative to max headroom (9dBu): 106dB
  • THD at medium gain (30dB): 0.0009% measured with a 1kHz –20dBu input signal and with a 22Hz/22kHz band-pass filter
  • Frequency response at minimum gain (0dB): –0.5dB down at 10Hz and –3dB down at 125kHz
  • Frequency response at maximum gain (60dB): –3dB down at 16Hz and –3dB down 118kHz
  • CMRR=98dB (Channel 1, 1kHz, maximum gain with +24 dBu input)
  • Crosstalk Channel to Channel: with 10dB@1kHz input to chA, chB output: 104dBrA. With 10dB@10kHz input to chA, chB output: 84dBrA
Line Input Response:
  • Gain range: –20dB to +10dB in 10dB steps +20dB of variable gain
  • Input Impedance: 10kΩ from 10Hz to 200kHz
  • Noise at main output with gain at unity (0dB): -96dBu measured with a 22Hz/22kHz band-pass filter
  • Signal to noise ratio relative to max headroom (24dBu)=120dB
  • Signal to noise ratio relative to 0dBFS (+22dBu): 118dB
  • THD at unity gain (0dB): 0.001% measured with a 0dBu input signal and with a 22Hz/22kHz band-pass filter
  • Frequency Response at unity gain (0dB): –0.3dB down at 10Hz and -3dB down at 200kHz
Instrument Input Response
  • Gain range: 10dB to 40dB continuously variable
  • Input Impedance:
  • High: greater than1 mohm
  • Low:greater than 300 kohm
  • Noise at minimum gain (+10dB): –92dBu measured with a 22Hz/22kHz band-pass filter
  • Noise at maximum gain (+40dB): –62dBu measured with a 22Hz/22kHz band-pass filter
  • THD at minimum gain (+10dB): 0.001% measured with a 10dBu input signal and with a 22Hz/22kHz band-pass filter
  • Frequency Response at 10dB gain with –10dB input: 10Hz-100kHz +/- 0.6dB
  • Frequency Response at 40dB gain with –40dB input: –2.5dB down at 10Hz and 0dB at 100kHz
High-Pass Filter
  • Roll off: 18dB per octave 3-pole filter
  • Fixed Frequency 75Hz measured at the 3dB down point
  • Moving coil (MC) meter is factory calibrated to 0VU: +4dBu with 1kHz sinewave
  • With the VU Cal button pressed the meter can be adjusted on the rear panel to allow 0VU to equal +10dBu to +26dBu with the centre detent being equal to +22dBu
  • Peak LED meters calibrated in the detent position for 0dBFS: +22dBu, calibration is adjustable on the rear panel to allow 0dBFS to equal +10dBu to +26dBu
  • Routing for MC and Peak1 meter is after the HPF, pre insert send or switched post insert return. Peak2 is always pre ADC channel 2, which can be fed by external input or Instrument input
  • LED levels are as follows when peak calibration is set to center detent on the rear panel (This is when using the internal ADC)
  • 0: +22dBu
  • 2: +20dBu
  • –6: +16dBu
  • –12: +10dBu
  • –18: +4dBu
  • –42: -20dBu
    Analog Channel Inputs:
    • Mic input: XLR x 1
    • Line input: XLR x 1 and TRS x1
    • Instrument input TRS Jack: XLR x 1
    • External ADC input: TRS Jack x 1
    • Return: TRS Jack x 1
    Analog Channel Outputs:
    • Send: TRS Jack x 1
    • Balanced line output: XLR x 1
    • DI output: XLR x 1
    • DI through: TS Jack x 1
    Analog Channel Additional I/O:
    • Cue mix left input: TRS Jack x 1
    • Cue mix right input: TRS Jack x 1
    • Headphones output: TRS Jack x 1
    • 8.6 Ib. (3.9 kg)
    Dimensions (HxWxD)
    • 8.66" x 4.1" x 10" - 11.4", (220mm x 104 mm x 254 - 290 mm)
    Related Products
    • ISA Stereo ADC (compatible with ISA 430 MKII and ISA One), ISA Stereo ADC (compatible with ISA 430 MKII and ISA One)
    All Focusrite products are built to the highest standards, and are designed to provide many years of reliable performance. In the event of a Manufacturing Defect becoming evident during the warranty period, Focusrite will ensure that the product is repaired or replaced free of charge. The warranty for any product purchased on or after the 1st January 2018 is a period of 36 months from the date of original purchase. The warranty period for products purchased on or prior to the 31st December 2017 is 24 months from the date of original purchase.

    A Manufacturing Defect is defined as a defect in the performance of the product as described and published by Focusrite. A Manufacturing Defect does not include damage caused by post-purchase transportation, storage or careless handling, nor damage caused by misuse.

    While this warranty is provided by Focusrite, it is fulfilled by Focusrite’s distribution partner in the country in which you purchased the product. To contact Focusrite's local distribution partner regarding a warranty issue, click here; they will advise you of the appropriate procedure for resolving the warranty issue. Note that many of the products returned under warranty are found not to exhibit any hardware fault at all. In the case of operational interruption, it’s worth checking other factors such as cables, drivers, software settings and the like, prior to returning your hardware. Contact Focusrite support first, if you experience technical issues.

    In every case you will need to provide a copy of the original invoice or store receipt to Focusrite’s local distribution partner. In the event that you are unable to provide proof of purchase, you should request a copy of your receipt from the reseller from whom you purchased the product. If you purchase a Focusrite product outside your normal country of residence, Focusrite’s distribution partner in your normal country of residence will not be able to honor this limited warranty, although you may request an out-of-warranty chargeable repair.

    This limited warranty is offered solely to products purchased from an Authorised Focusrite Reseller. This Warranty is in addition to your statutory rights in the country of purchase.

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