cliveb;421451 Wrote: > It doesn't work quite like that. > > First of all, the Replaygain algorithm doesn't use peak levels. It > determines the perceived loudness based on RMS levels and the ear's > varying sensitivity at different frequencies (using the Fletcher-Munson > curves, I believe). > > Secondly, the 89dB reference level is derived from an SMPTE standard > which states that pink noise at -20dB RMS should be played at 83dB SPL. > (Replaygain started out using 83dB as its target loudness, but that's > been adjusted up to 89dB for reasons that are not entirely clear to me. > Most software that performs Replaygain calculations will let you set the > reference level to whatever you like: 89dB just seems to have become > some sort of de-facto standard). So in other words, if you use an 89dB > reference level for Replaygain, you'll get the same perceived loudness > as you'd get listening to pink noise at -14dB RMS.
yeah - I get all of that. But replaygain can't possibly know what the gain of my amplifier is or what the efficiency of my speakers are so it can't actually know what the absolute replay SPL is going to be... I also understand the peak vs. RMS issue. The thing I don't get is how it could conclude that it is possible to have an effective RMS level that is higher than the possible max peak value. The Fletcher-Munson curves are level dependant so I don't think that can cover it... I just wonder if the ReplayGain algorithms aren't perfectly optimised for hypercompressed material? - this is pure speculation on my part. Anyway, back to the plot... what does SeeDeClip do with non-clipped stuff and really badly (crudely) clipped stuff... ? -- Phil Leigh You want to see the signal path BEFORE it gets onto a CD/vinyl...it ain't what you'd call minimal... SB3 (wired) - TACT 2.2X (Linear PSU) + Good Vibrations S/W - MF Triplethreat(Audiocom full mods) - Linn 5103 - Aktiv 5.1 system (6x LK140's, ESPEK/TRIKAN/KATAN/SEIZMIK 10.5), Townsend Supertweeters, Blue Jeans Digital,Kimber Speaker & Chord Interconnect cables Outdoors: Boom ------------------------------------------------------------------------ Phil Leigh's Profile: http://forums.slimdevices.com/member.php?userid=85 View this thread: http://forums.slimdevices.com/showthread.php?t=57872 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
