[sdiy] I2C DAC

[Bruce Duncan]

I've been looking into DACs lately with regards to Audio vs Control.
 From what I understand the main difference is that audio DACs have 
interpolation filters built in to reduce out-of-band spectra.
They also oversample to place the frequency of the "image" that 
creates inverted copies of the signal into a region that makes it 
easier to filter down-line.

Would I be correct in saying that these features are more important 
when playing back sampled material vs generating signals like a digital OSC?
Oversampling a 12bit sine wave at x256 that is 48kHz and 
interpolating between steps and then outputting at the same sample 
rate 48K does not create any new data..or does it.
Would the sound be any better using an audio DAC vs a voltage out 
control type dac given the same sample rate and bit depth?

These are the questions I ask myself.

The main reason is that audio DACs nead an I2S or codec interface and 
that is a lot more difficult to find than a SPI port on many uC.

Bruce