"Arny Krueger" wrote
... in which case your D-A is severely broken, unless you've
intentionally disabled the reconstruction filter !

In this day and age, the reconstruction filter is so tightly integrated
into
the DAC chip that disabling it is not an option. I took this to be a
philosophical, not a practical discussion. There actually have been PC
sound
cards that lacked a brick wall filter, AFAIK the SoundBlaster Pro was one
such card.

Hi Chaps,
I've actually done this myself - a college project, write an assembler
routine to generate an audio sinewave on a Z80 based dev system - the DAC
outputs were unfiltered (I could get a pretty crisp 2MHz full-scale
squarewave out of it), and with an 8-bit
staircase-pretending-to-be-a-sinewave at 1 KHz delivered to a 5" speaker, it
sounded reasonably clean. BTW, Radium has a tendency to ask odd questions -
i think the radiation has affected hid mind ;o)

Dave H.
(The engineer formerly known as Homeless)