Back to definitions: Cliveb is right, his definition of oversampling, is the original, and if using a straightforward old 14 bit or 16 bit current source DAC is true.
Virtually all 24 bit DACs including the Transporter AK4396 use some form of Delta Sigma DAC. In the AK4396 it is still multi-bit but not 24 bit! In the ultimate case many DACs can be one bit, this guarantees fantastic easy linearity. However the sampling rate required to use these low bit DACs would be astronomic if using a basic oversampling technique alone. This is where all the DAC black magic starts - first there is simple oversampling to get higher sample rate, then a digital filter, usually multiple order, is used to achieve noise shaping. This moves the DAC conversion noise that is massive with low bit DACs, up to a high frequency band, that is easily removed post DAC. This is up-sampling, it has filtering coefficients, dither etc. not just basic stuffing of new values. It is not just BS. You would need a sample rate of many MHz to achieve 24bit DAC resolutions without it. The clever bit the manufacturers don't seem to brag about is that once you have done your digital magic upfront, the DAC being 1 bit 4 bit or 8 bit is a easy and cheap, and similarly the post DAC recovery filtering is relatively easy and cheap. This moves all the design and cost issues to clocks, power and good analogue design practice. Dave -- DaveWr ------------------------------------------------------------------------ DaveWr's Profile: http://forums.slimdevices.com/member.php?userid=9331 View this thread: http://forums.slimdevices.com/showthread.php?t=69145 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
