Focusrite ISA828 ADC Card for ISA828

Overview

The ISA eight channel 192kHz A-D converter outperforms every other converter yet devised, and was the first audio A-D converter to utilise Burr-Brown Pro Audio Amplifiers and flagship PCM4220 A-D converter chips. With cutting-edge conversion technology seated within Focusrite custom analogue circuitry, the card delivers unparalleled performance; specifications include a dynamic range of 122dB and jitter less than 250 picoseconds. More information about Focusrite's ISA A-D converters can be found on the right.

 

The card can be retrofitted to an ISA428, ISA428 MkII or ISA828 at any time and, thanks to its convenient 25-pin D-Type connector, integrates seamlessly with Pro Tools HD as well as other popular hard disk recorders and mixing desks.

 

All eight converters are always available with this option, even when using the ISA428 and ISA428 MkII. When installed in one of these four-channel mic preamps, the the extra 4 converters of the A-D card are fed by four XLR inputs on the back labeled "ADC Input".

 

Digital formats include an eight-channel single/dual wire AES/EBU and S/PDIF output, as well as an eight-channel ADAT lightpipe (SMUX/SMUX2) output. Word clock i/o is provided via dedicated BNC connectors.

 

Specifications

We always quote 'real world' performance figures (measured to the AES17 standard). Some companies choose to quote chipset performance, which is misleading.

 

Output formats (All channels)

• AES/EBU (5V / 110 ohms), S/PDIF (0.8V / 75 ohms)

• ADAT lightpipe (SMUX I/II/IV, channels 1-4 only in 176.4kHz, 192kHz mode)

• S/PDIF lightpipe (channels 1-4 only; mutually exclusive with ADAT lightpipe)

 

Bit depth

24 bits, internally configurable to 16 or 20 bits if necessary.

 

AES3 output jitter

<:1500ps, 50Hz-100kHz

<:350ps, 700Hz-100kHz

 

Frequency response

All ranges: 20Hz–20kHz ± 0.3dB (100Hz–20kHz ± 0.1dB)

176.4kHz, 192kHz : 17Hz–90kHz ± 0.5dB

 

THD+n 

–121.5dB A-weighted, audio band-limited, 1kHz, -60dB FS input

Maximum 0.0033% at –1dB FS (1kHz)

Minimum 0.0008% at –15dB FS (1kHz)

 

Idle channel noise

117.5dB at 44.1kHz, CCIR-weighted, full bandwidth

 

Crosstalk 

–100dB at 12kHz

 

(paired channels) 

–95dB at 20kHz