Thanks, Serge. Looks like Crystal style the CS4398 as their 'flagship'
DAC (though I know at least one designer who prefers the CS4397). there
does seem to be an evaluation board. These references may help:

http://sharewave.com/en/products/pro/techs/T2.html details of Crystal
DAC chips
http://sharewave.com/en/pubs/rdDatasheet/CDB4398.pdf Evaluation board

There'a also a company that does a digital board with the CS4398 for
$495, but this does need in input chip.
http://www.aplhifi.com/index.html
". If you'd like to use I2S connection, you can send it directly to
the DAC board without digital receiver. The DAC accepts I2S, MSB and
LSB digital formats. It needs 8-9 volts filtered unregulated DC and it
has differential outputs from each DAC so you will need some sort of
filtering and tube or solid state stage with differential inputs. The
output amplitude on each output is around 1V RMS with 0db PCM"