Re: 14-bit DAC
Using those DACs with an oversampler ahead of them does TWO things for you, if you do 4x oversampling as Philips sedigned them for, you not only get approximately 2 bits more resolution (the oversampler effectively controls the average of quads of samples to insert those extra 2 bits of resolution into the analogue signal) but it also pushes the sampling frequency at the DAC up by a factor of 4. This makes the anti-alias reconstruction filter that is needed after the DAC an awful lot easier. The 44.1kHz sample rate inherent in CDs forces the use of a very tight analogue filter. This creates droop, ripples in the frequency response, and large phase shifts towards the edge of the passband.
So you may not feel the need for the resolution improvement from oversampling, but the easing of the requirements on the AA filter is most worthwhile. This one factor is ample justification for even the one-bit oversampling DACs.
David
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Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done
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