Archimago wrote: > Thank you for the link Mr. Krueger! > > So, I feel like I'm missing something here and curious about practical > implications: > > 1. As for the actual claims of "The Audibility of Typical Digital Audio > Filters in a High-Fidelity Playback System" per the title, what exactly > did they find here? (Other than suboptimal dithering being audible...) > >
Since they didn't test filters that were "Typical Digital Audio Filters in a High-Fidelity Playback System" and instead tested filters with a misch-mash of parameters with inherently flawed listening tests of their own contrivance; they found out what their inherently flawed listening tests revealed related to that cats-and-dogs set of filters. The paper was about straw men. The other big straw man came from a lack of understanding of ABX testing as it is practiced today in audio. They referenced a 1950 paper about an early form of ABX testing that was not the interactive process that is used in audio today. When corrected, they went back and referenced a later paper that cited the same 1950 paper. I guess you can't teach old dogs new tricks. At any rate their excuse for ignoring ABX testing was a repetition of the false claim that ABX is necessarily a 2AFC listening test which as a practical matter is not true. ABX as practiced today is interactive and therefore many choices about how to execute the test are up to the listener. The listener has the option of using ABX as a same/different test, and many say they exercise this option. The paper's own test methodology locked their listeners into fixed-length arbitrary samples, while many ABX testers prefer shorter samples of their choosing. What we know about how people detect audible differences favors shorter samples of the listener's choosing. > > 2. What device uses 16-bit RPDF dithering which would be of any > significance for the hi-fi enthusiast these days? I have no idea of any such device being commonly used. Hi Fi enthusiasts generally only use DACs, and unlike ADCs, dither is not central to the operation of DACs. The predominate source of dither involved with a typical piece of hi fi gear is generally the digital recording. If we adopt the model of recordings being made with ADCs that have less noise then their sources which seems reasonable, then the actual dithering noise in the recording can easily be the background noise from acoustical and analog sources that are an inherent part of the recording process. Analog noise generally has a Gaussian PDF which more strongly resembles TPDF dither than RPDF dither. 5 ------------------------------------------------------------------------ arnyk's Profile: http://forums.slimdevices.com/member.php?userid=64365 View this thread: http://forums.slimdevices.com/showthread.php?t=103537 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
