> I think there's a lot of subtlety being missed between dynamic range and resolution. For example, I think your JND (just noticeable difference) assumption is

> I think there's a lot of subtlety being missed between dynamic range and resolution. For example, I think your JND (just noticeable difference) assumption is incorrect; my understanding of the scientific consensus is that a 1db difference at any volume is consciously perceivable to "normal" human hearing (and 3db to virtually all humans), and a 0.2db difference has been shown to be subconsciously perceivable by most. The Wikipedia article about JND seems to imply that the general 1 dB rule may not necessarily apply near the limits of perception. I haven't found a whole lot of more detailed information; however, the table I linked in the edit to my previous comment seems to indicate that the JND in dB gets much higher at very quiet volumes. > For example, the point made about near infrared being invisible to all humans is obviously false: most humans can't, but a certain percentage of blue-eyed humans can see near infra-red (including remote control IR) The article does mention that at some IR remotes can be visible: > Can you see the Apple Remote's LED flash when you press a button? No? Not even the tiniest amount? Try a few other IR remotes; many use an IR wavelength a bit closer to the visible band, around 310-350THz. You won't be able to see them either. The rest emit right at the edge of visibility from 350-380 THz and may be just barely visible in complete blackness with dark-adjusted eyes. All would be blindingly, painfully bright if they were well inside the visible spectrum. It has a footnote with more detailed information: > The original version of this article stated that IR LEDs operate from 300-325THz (about 920-980nm), wavelengths that are invisible. Quite a few readers wrote to say that they could in fact just barely see the LEDs in some (or all) of their remotes. Several were kind enough to let me know which remotes these were, and I was able to test several on a spectrometer. Lo and behold, these remotes were using higher-frequency LEDs operating from 350-380THz (800-850nm), just overlapping the extreme edge of the visible range. I don't have enough time or knowledge to really dive in to the scientific studies. That being said it's worth noting that a large number of studies that have found no perceptible difference between CD-quality and higher-resolution audio, and (as you mention) there are a lot of ways for minute hardware differences to skew the results either way. > Dithering is a kind of compression algorithm that encodes a greater dynamic range within a signal with an artificially constrained dynamic range Dithering does more than just expanding the dynamic range: it ensures that quantization error produces a predicable noise floor rather than input-dependent distortion. This video, by the author of the xiph.org article I linked before, has a good explanation and demonstration of dithering (use the chapter selection menu to skip to the "dither" section): https://xiph.org/video/vid2.shtml https://xiph.org/video/vid2.shtml