Focusrite Introduces ISA428 MkII Mic Preamp, A/D Converter

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Focusrite announces the ISA428 MkII ($1,799.99 MSRP) 4-channel mic preamp and A/D converter, which the company says will supersede the existing ISA428. Like its predecessor, the ISA428 MkII features four of Focusrite's transformer-based ISA preamps, which are found in the Focusrite Forte console, as well as the same analog circuit board as the ISA428. Each channel has phantom power and phase-reverse controls, plus switchable input impedance and an adjustable highpass filter.

Mirroring the feature set of the original model, the MkII also has an optional 8-channel A/D converter upgrade, which converts signals from the preamps and an additional four line-level inputs to 24-bit digital data streams at sample rates of up to 192 kHz. New to the ISA428 MkII is a switched-mode power supply, which lowers the unit's internal noise and heat output, and is said to greatly reduce the unit's weight.

Instead of the large moving-coil peak meters of the ISA428, the ISA MkII's metering duties are handled by per-channel, six-step LED bar graph displays, which monitor the signal prior to the A/D stage and are designed to provide an accurate status of the preamp's output level. Focusrite also removed the ISA428's soft limiter feature, instead providing precise calibration figures in the user manual to enable accurate system setup.

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“More and more people are making high-quality recordings outside the traditional studio environment, and they have different requirements to recording studios: they want the same high-quality audio, but in a simpler package," says Focusrite’s Director of Product Strategy, Rob Jenkins. "So the objective with the ISA428 MkII was to create a leaner, more cost-effective design that maintained the Focusrite sound. The new power supply helped us achieve this, and it actually runs cooler with less noise and interference than the previous model.”

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