QWhen researching DACs, I ran across the Cambridge Audio CXN, a network audio player that upsamples all inputs to a 24-bit/384kHz hi-res format using “polynomial curve fitting interpolation.” This seems to be the only DAC that offers that kind of feature. Most Ultra HDTVs and Blu-ray players also provide upscaling, but for video. In my experience, this is a very effective feature that improves the experience of watching a regular DVD. Here’s my question: Does audio upsampling have the same effect as video upscaling? —Mike Yang / via e-mail