Focusrite ISA428 MkII Rackmount 4-Channel Microphone Preamp
9,495.00 Excl. VAT
- Four ISA series transformer-based preamps
- Eight-channel optional A-D converter
- Selectable impedance
- Four front panel instrument inputs
- Dedicated analogue insert points
- Accurate LED meters for every channel
Available on backorder
ISA428 MkII
4-channel Microphone Preamp
Now in its second generation, the ISA 428 Mk II 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 one 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 Mk II 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 Mk II is a precision eight-channel A-D converter with 122dB dynamic range and superb jitter performance — ideal for simple interfacing with your DAW (sold separately).

Four classic mic pres
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 one small change, adding three additional input impedances to the classic ISA 110 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.
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 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. An array of 6-segment LED meters show peak signal level for the four mic pres, in addition to the four direct inputs to the optional A-D card. Switchable rear-panel insert points allow the use of inline processors such as compression.

Brainworx bx_console
The Focusrite Studio Console reborn in your DAW

| Weight | 5.44 kg |
|---|---|
| Dimensions | 65.53 × 37.59 × 13.21 cm |
| Analog Inputs: | 4 x XLR (Mic), 4 x 1/4″ (Line), 4 x 1/4″ (Hi-Z), 4 x 1/4″ (Returns), 4 x XLR (Aux) |
| Digital Inputs: | Optional A/D expansion card available (digital DB25, optical) |
| Frequency Response: | 20Hz-122kHz |
| Phantom Power: | Yes |
| Power Supply: | Standard IEC AC cable |
| Rack Spaces: | 2U |
| Gain Range (Mic): | 0dB to 60dB in 10dB steps, plus 0dB to 20dB continuously variable trim |
| Gain Range (Instrument): | 10dB to 40dB continuously variable |
| Gain Range (Line): | -20dB to 10dB in 10dB steps, plus 0dB to 20dB continuously variable trim |
| SNR (Mic): | 123dB (relative to max output 25dBu) 120dB (relative to 0dBFS ( 22dBu) |
| SNR (Line): | 116dB (relative to max output 25dBu) 113dB (relative to 0dBFS 22dBu). Input Impedance: 10kO |
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