I have read many glowing accounts of the Chord Blu MK 2 Scaler and the Sony DSEE HX, both of which seem to me to claim to "restore" information missing from standard CD recordings at 16 bits, 44.1 k samples/sec. The mental picture, as drawn by Sony, looks like this: The enhancement (left) extends the bandwidth of the signal far beyond the yellow segment that truncates at mid frequency (right, the yellow portion). What? Does this really work? This is taking information not in the signal, but making some guess, I guess, given the spectrum up to 20 KHz, how it might extend to the higher reaches addressed by high-resolution, higher-sampling rate, audio. If it DOES work, are there products that do this off line? The Chord Scaler costs upward of $10K to do this in real time on a standard CD, keeping up with the signal from the disc. It would seem that one could also off-line process the CD signal to end up with this upscaled, bandwidth-extrapolated, "better" signal. By the way, the Sony DSEE-HX is described as only applying to recordings at less-than-CD rates, e.g. MP3 128kb/sec perhaps, as a way of restoring some of the "missing" information, but when I listen on my Sony NW-WM1A with and without this feature turned on, I only hear difference, not improvement.