David Adler wrote: > On Mon, Jul 18, 2011 at 12:13 PM, Renato wrote: > > On Mon, 18 Jul 2011 11:53:47 +0200 > ... > > isn't it useless going way above 24 bits, since that's what in the end > > the DAC (sound card) will use? as far as I can remember, delta-sigma > > DACs don't go over 24 bit, do they? > > > More than 24 bit for DAC/ADC is useless, going above 24 bit for > internal processing is not. The latter ensures that rounding errors > that may be introduced by multiple math operations disappear when bit > depth is finally reduced again to 24 before entering the DAC. Do not confuse DAC/ADC bit width with bit widths used during DSP calculations. The two are basically orthogonal. > The magnitude of rounding errors depends on the type and number of > operations done. I don't know the limits, but for what Fons calls > "normal audio engineering practise" (see his posting above), 32 bit is > enough. For audio data paths this is true. For the intermediate results during complicated calculations (eg filters and reverbs) double precision makes things easier and is basically available for free. Erik -- ---------------------------------------------------------------------- Erik de Castro Lopo http://www.mega-nerd.com/ _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
