On Sat, Feb 13, 2010 at 5:10 PM, <fons@xxxxxxxxxxxxxxx> wrote: > On Sat, Feb 13, 2010 at 03:07:21PM -0600, Brent Busby wrote: > >> It seems that with CD's, you're cursed one way or another nomatter what >> era they come from. In the 80's CD's, you have the gritty metallic >> sound that comes from inappropriate EQ that was mentioned, > > If that were the real problem then applying the inverse > EQ would solve it (and you'd gain some S/N ratio as well). > Try it and you'll find it doesn't work that way. The RIAA preemphasis is not a biorthogonal filter. There will always be at a minimum some phase/group delay as the 'perfect' inverse filter is unstable. You can only approximate it. Another example of an analog horror we no longer need to put up with in the digital era :-) A digital EQ alone isn't even close, as digital EQ is nearly always phase-linear (acausal). It's a completely different style of filter. Also, the preemphasis is only part of it; mastering engineers of the day mixed and mastered for the medium, so they did a bunch of things that only make sense for vinyl. Monty _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
