At the heart of the stereo A/D card is a high quality 24-bit 96 kHz Delta Sigma converter
running at 128x oversampling for maximum conversion performance. Focusrite proprietary
designs are used for all internal clocking and phase lock loop circuits to guarantee the
absolute minimum jitter possible, whether free-running or locked to wordclock or Pro Tools
When recording to non-24-bit destinations, 16- and 20- bit dithering can be selected to
ensure the highest quality digital conversion for any format. The ISA’s optional A/Ds are
stereo and allow for input from internal (post-processing) and external sources simultaneously
giving a clean, protected, high-quality path to stereo digital media.
INT (Internal Signal)
The internal input to the A/D is normally fed from the internal channel signal passing through
the EQ and dynamics. However, this path can be broken by a signal connected to the rear INT
A/D Direct jack, which allows a signal to be directly connected to the A/D input (replacing the
internal processed signal).
EXT (External Input)
An additional external input (XLR on the rear panel) gives the user access to the second channel
of conversion on the A/D card for stereo recording with two units or for an additional external source.