The ISA 428 ADC from Focusrite is an analog to digital output expansion card for the ISA 428 microphone preamp and provides eight channels of conversion at frequency rates of up to 192kHz.
Digital output formats include eight-channel of single/dual wire AES/EBU, eight-channel of S/PDIF and single/dual port eight-channel ADAT Lightpipe.
Two ISA428s can be used with a single ADC, utilizing the four extra line inputs on the rear of the unit containing the optional ADC.