well i'm not here to talk about whether or not i can discriminate dither from music, it is pointless for me as someone who listens to music
On Mon, Jan 10, 2022 at 12:31 PM vicki melchior <[email protected]> wrote: > No, I never said that dither becomes a coherent signal. Dither is noise. > > > On Jan 10, 2022, at 12:14 PM, Zhiguang Zhang <[email protected]> wrote: > > Vicki, > > that is rather incredible to me if true, that dither is detectable as a > coherent signal but i suppose that the dither that i was referring to is > *necessarily* a part of the program material signal because it is the > dither that has already been added during the recording chain and thus not > a separate coherent signal > > https://ask.audio/articles/the-how-and-why-of-dithering-in-pro-tools > > On Mon, Jan 10, 2022 at 9:15 AM vicki melchior <[email protected]> > wrote: > >> Eric, I’m not sure I get the gist of your question, but “hearing into the >> noise” refers to the fact that coherent signals can be detected at some >> level (around 10-15 dB) below the RMS level of the noise (whether the noise >> is dither or part of the signal). The mathematical analogy for this is >> coherent/noncoherent gain; the hearing system integrates both noise and >> signal over the bandwidth of the particular cochlear filter. Noise >> integrates non-coherently while signal integrates coherently, leaving a net >> gain in SNR. This is relevant for a number of reasons. First, you can >> (maybe) detect actual signal at those depths below noise. But second, you >> can also hear distortion lying well below the noise floor if it is >> relatively coherent, especially the peaks associated with truncation >> distortion when dither has been omitted. These arguments are highly >> relevant to determining the bit depth needed to convey program material, >> and that in turn, is a function of the dynamic range audible to humans >> along with an understanding of the noise sources present in the given >> system. So it is not about hearing the noise, but rather hearing signal >> below the noise floor. >> >> >> On Jan 9, 2022, at 8:10 PM, Zhiguang Zhang <[email protected]> wrote: >> >> not sure if this point is important, but the dither that is added before >> you hear the program material being reproduced isn't actually supposed to >> be 'heard' - so this argument doesn't appear to make much sense in my >> mind. engineers might hear the dither when they're familiar with the >> studio that they work in, but past that, i'm not sure i get the point of >> discussing the practical limits of hearing something added which, for all >> intents and purposes, is hidden. it's almost like you're trying to reverse >> engineer what recording interface an audio engineer was using >> >> On Sun, Jan 9, 2022 at 5:48 PM Brian Willoughby <[email protected]> >> wrote: >> >>> Thank you for these titles. I've already found them in the AES library. >>> >>> Brian Willoughby >>> >>> >>> On Jan 9, 2022, at 13:43, vicki melchior <[email protected]> >>> wrote: >>> > As far as measurements of how far “into the noise” we can hear, there >>> aren’t a lot of good published numbers that I know of (having reviewed the >>> subject a couple of years ago), but Bob Stuart and Peter Craven argue >>> dynamic range and, to a certain extent, audibility below the noise floor in >>> a couple of papers published in JAES in 2019. They are based on >>> psychoacoustic arguments as well as listening test results, the latter as >>> part of their studio and lab work on MQA. If interested, their (open >>> access) papers are in the AES e-lib, “The Gentle Art of Dithering” and “A >>> Hierarchical Approach for Audio Capture, Archive and Distribution”. >>> >> >> >
