Phil Leigh;421418 Wrote: > If my maths is right (?) then this is a bit baffling since the max 16 > bit dynamic range/snr is 98.08dB and that would lead you to expect a max > replaygain of -9dB to 89dB... 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. -- cliveb Transporter -> ATC SCM100A ------------------------------------------------------------------------ cliveb's Profile: http://forums.slimdevices.com/member.php?userid=348 View this thread: http://forums.slimdevices.com/showthread.php?t=57872 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
