Upsampling files

Being new to computer audio, I referenced the series of articles by Zellig and Clawson published a few years ago in The Absolute Sound. Their reference source for playback was the PWT and PWD. They reported a significant improvement in sound quality as the result of upsamplling files once ripped from CD’s.

Since the newer DS Dac upsamples source files to DSD, I’m wondering if upsampling ripped files that are stored on the music server’s hard drive now becomes a moot point in terms of improving sound quality?

Welcome, Howard!

As a Gedankenexperiment I hypothesize upsampling to not make a positive difference with the DS. But I admit to not making the actual comparison.