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Focusrite // The ISA 428 & 828 with Damian Taylorplay button

Focusrite // The ISA 428 & 828 with Damian Taylor

Focusrite

collapse expand iconDescription

Focusrite's ISA mic preamps can be traced back to 1985, when console designer Rupert Neve was asked by Sir George Martin to create new modules for the console at AIR Montserrat. The modules he created included the legendary ISA110, on which all ISA microphone preamps are based. With their characteristic Lundahl LL1538 input transformer, along with one concession to modernity—variable input impedance—ISA mic preamps are very much the same as they were 30 years ago. But today, instead of solely gracing the consoles at AIR, ISA mic pres are at the heart of hundreds of hits made in leading studios and by leading engineers, artists and producers, across the world.

Now in its second generation, the ISA 428 MkII incorporates four of Focusrite's renowned mic pres in a simple-to-operate 2U enclosure, placing four mic preamps, instrument inputs and line ins at your fingertips. The original Focusrite mic pre was designed to suit the microphones of the time; today's model makes a small change, adding three additional input impedances to the classic ISA110 setting, allowing you to match any microphone, old or new, and access a wide range of sounds, from the character and warmth of a vintage mic to the clear transparency of a modern design. Or, you can experiment and bring out just the qualities you want.

In addition to the mic inputs, there are four front-panel instrument inputs, making the ISA428 MkII ideal for overdubs in the control room with no need for a DI box. On the back: four line inputs and switchable insert points on each channel to allow routing via external signal processors. There's also a versatile, vintage design variable high-pass filter to control what's going on at the bass end. And finally, accurate, 6-LED meters to tell you exactly what's going down. Optionally, available for the ISA428 MkII is a precision eight-channel A-D converter with 122dB dynamic range and superb jitter performance (sold separately)—ideal for simple interfacing with your DAW.

UPDATE: 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 ISA428 MKII 4-Channel Microphone Preamp
Focusrite ISA428 MKII 4-Channel Microphone Preamp
Focusrite ISA428 MKII 4-Channel Microphone Preamp

collapse expand iconFeatures

  • Four ISA series transformer-based preamps
  • Eight-channel optional A-D converter
  • Selectable impedance
  • Four front panel instrument inputs
  • Dedicated analog insert points
  • Accurate LED meters for every channel
  • Focusrite offers a 2-year manufacturer's warranty

collapse expand iconSpecs

Mic Inputs
  • Frequency response at minimum gain (0dB): –0.35dB at 20Hz and –3dB at 122kHz
  • Frequency response at maximum gain (60dB): –2.5dB at 20Hz and –3dB 103kHz
  • Gain range: 0dB to +60dB in 10dB steps, plus 0dB to +20dB continuously variable trim
  • Maximum headroom: +7.4dBu
  • THD+N: 0.0009% (measured at 1kHz –20dBu input signal, at 30dB gain setting, with a 20Hz/22kHz bandpass filter)
  • Noise EIN: –126dB (measured at 60dB of gain with 150 ohm termination and 20Hz/22kHz bandpass filter)
  • Noise at main output with unity gain: –98dBu (measured with a 20Hz/22kHz bandpass filter)
  • SNR: 123dB (relative to max output 25dBu)
  • SNR: 120dB (relative to 0dBFS (+22dBu)
  • CMRR: 88dB
  • Input Impedance, variable: 600 ohm, 1,400 ohm, 2,400 ohm, 6,800 ohm
Line Inputs
  • Frequency Response at unity gain (0dB): –0.3dB at 20Hz and –3dB at 94kHz
  • Gain range: –20dB to +10dB in 10dB steps, plus 0dB to +20dB continuously variable trim
  • Maximum headroom: +25.4dBu
  • THD+N: 0.002% (measured with +4dBu input signal, 0dB gain setting, with a 20Hz/22kHz bandpass filter)
  • Noise at main output with unity gain: –91dBu (measured with a 20Hz/22kHz bandpass filter)
  • SNR: 116dB (relative to max output 25dBu)
  • SNR: 113dB (relative to 0dBFS +22dBu). Input Impedance: 10 kohm
  • Instrument Inputs
  • Frequency Response at +10dB gain: -0.2dB at 20Hz and 0dB at 200kHz
  • Frequency Response at +40dB gain: -3dB at 20Hz and -3dB at 38.4kHz
  • Gain range: +10dB to +40dB continuously variable
  • Maximum headroom: +11.5dBu
  • THD+N: 0.006% (measured with -20dBu input signal, at minimum gain (+10dB), with a 20Hz/22kHz bandpass filter)
  • Noise at main output with minimum gain (+10dB): –95dBu (measured with a 20Hz/22kHz bandpass filter)
  • Input Impedance = >1 mohm
High Pass Filter
  • Roll off = 18dB per octave 3 pole filter
  • Frequency range: 16Hz to 420Hz (continuously variable, measured at the 3dB down point)
Meters
  • 6 LED meter is calibrated 0dBFS = +22dBu (the maximum level which can be correctly converted by the optional internal A/D converter before overload occurs). The meter calibration points are as follows:
  • Meter panel calibration value in dBFS/equivalent dBu value
  • 0dBFS/+22dBu
  • -2dBFS/+20dBu
  • -6dBFS/+16dBu
  • -12dBFS/+10dBu
  • -18dBFS/+4dBu
  • -42dBFS/–20dBu
Front and rear connectivity
  • Analog Channel Inputs (Inputs 1-4)
  • 4 instrument 1/4" TS jack inputs on front panel
  • 4 microphone XLR inputs on rear panel
  • 4 line 1/4" TRS jacks on rear panel
  • 4 insert return 1/4" TRS jacks on rear panel
  • 4 ADC XLR inputs on rear panel
Analog Audio Outputs (Outputs 1-4)
  • 4 line XLR outputs on rear panel
  • 4 insert send 1/4" TRS jacks on rear panel
Other I/O
  • IEC power input connector 100Vac–240Vac
  • Front Panel Indicators
  • 8 output meters, 6 segment
  • 4 30–60 mic gain range selection indicator
  • 4 +48V phantom power indicator
  • 4 Phase indicator
  • 4 Insert In indicator
  • 4 Filter In indicator
  • 4 Input selection indicators (Mic, Line, Inst)
  • 4 Z In microphone input impedance selection indicators (Low, ISA110, Med, High) Clock select indicators (44.1, 48, 88.2, 96, 176.4, 192)
  • Ext. clock indicators (Lock, Word clock, 256X)
  • Weight: 12.2 lb. (5.5 kg)
  • Dimensions (WxHxD): 480 mm x 88 mm x 280 mm, 19" x 3-1/2" x 11"

collapse expand iconWarranty

All Focusrite products are built to the highest standards and should provide reliable performance for many years, subject to reasonable care, use, transportation and storage.

In the event of a Manufacturing Defect becoming evident within 12 months from date of purchase Focusrite undertakes that the product will be repaired or replaced free of charge if the product is returned to the authorised dealer from whom it was purchased. In these circumstances, or if you need an out-of-warranty repair to your Focusrite product, please contact your local Focusrite distributor in your country of residence or business : Find your local distributor here and you will be advised of the correct return procedure.

Alternatively contact the Focusrite Reseller from which you purchased the product. If you purchase a Focusrite product outside your country of residence or business you will not be entitled to ask your local Focusrite Distributor to honour this Limited Warranty, although you may request a chargeable repair.

Alternatively, the unit may be returned at your cost to the dealer you purchased the unit from so that they can organise a Warranty repair with their Focusrite Distributor.

This Warranty does not include cost of shipping to and from the authorised dealer from whom it was purchased. In every case it will be necessary to provide the original invoice or store receipt to accompany the defective product to the supplying dealer. This Limited Warranty is offered solely to the first purchaser of the product from an Authorised Focusrite Reseller (defined as a reseller which has purchased the Product directly from Focusrite Audio Engineering Ltd. in the UK or its Authorised Distributors outside the U.K,) and is not transferable.

This Warranty is in addition to your Statutory Rights in the country of purchase.

Please note: A Manufacturing Defect is defined as a defect in the performance of the product which may be expected from a reasonable interpretation of the published description and performance specifications as published by Focusrite Audio Engineering Ltd. This does not include damage caused by post-purchase transportation, storage or careless handling, nor damage caused by misuse.

A significant proportion of products returned under Warranty (which are very few in number compared to numbers sold) are found not to exhibit any fault at all. Please check that the mains voltage is correctly set for your local supply and that your connecting cables are in good order and correctly connected.

If in doubt about the product functions please read the user guide and if necessary contact your dealer for advice before returning the product to the supplying dealer. You can also contact the Focusrite Tech Support team at the Focusrite Answerbase for general advice.

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collapse expand iconReviews

5

1 Reviews

0%

of respondents would recommend this to a friend

Reviewed by 1 customers

  • great pice of gear for recording!

    5

    submitted11 years ago

    bymoises guillen

    fromweslaco

    i used it first on drums, on kick snare and overheads and it sounds very nice. is not so colored like other brands but it gives the weight i need to the instruments i record. i used on bass and sounds amazing too compared to my focus rite pro 40 preamps i can hear the difference. i recommended greatly!

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