I have reported on exaSound DACs since the introduction of the e18 in 2013, but those reports were in my Music in the Round column. This is Stereophile's first full review of an exaSound product and the first time one has spent time on JA's test bench.
A digital front end comprises several elements: data storage, library management, program control, signal distribution, signal conditioning, and digital-to-analog conversion plus all the necessary interconnections. All this can be contained in a convenient single box, or it can be distributed.