Well I suppose this thread could grow and grow, debating the hot topics of definition, which probably varies by continent.
In my understanding we have oversampling, which is usually a relatively simplistic method of generating intermediate samples - you have to create new points that weren't there originally. In up-sampling, there is a digital filter algorithm which can have a whole variety of mechanisms to generate the new extra samples + appropriate dither mechanisms. The words are used by many people apparently interchangeably. In the Linn document, I referred to earlier, this whole DAC pre-processing they call upsampling, indeed their software updates actually change this whole pre DAC chain. In the AK4396, there is also a set of digital filter interpolators to create the extra samples, what algorithms they use is probably a trade secret, but I think to just call it oversampling would be a little unfair. The problem I see with all this SOX filter / up-sample is that unlike Linn and several other vendors you can't fully over-ride the on chip pre-DAC digital filters. You will get variations because as you change the sample rate in, the DAC will change its digital filter characteristics. Secondarily a lot of this up-sample work with different filters will change (improve?) the transient performance of 16 bit 44.1k signals that had less than optimum ADC recording / translation originally. In traditional R-2R ladder type DACs where all bits are used (not that common in new components) the advantage of up sampling is that you will tend to get better filter performance from a multi rate DAC. Its not the words that counts but what actually happens, and in this threads case, what the sum of all the processing steps achieve. In the excitement over apodizing filters, views seem very mixed. Bob Stuart of Meridian fame, generally highly regarded, states that the significant increase in post transient ringing with apodizing filters is OK, the ear mechanism apparently shuts this out post transients. He is probably right, but others in the industry seem to disagree. Well that's always been the audiophile world....... 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
