On Monday 28 November 2005 16:18, Robert Denier wrote: > On Monday 28 November 2005 02:08 pm, Nick wrote: > > On 25/11/05, Phill Edwards <[EMAIL PROTECTED]> wrote: > > [snip] > > > That's because the S/PDIF is outputting a digital stream which the > > receiver decodes and is responsible for amplifying. I don't think it's > > possible to dynamically adjust a digital audio stream before it hits > > the amp. > > It is always possible to scale numbers and a digital stream is just a > stream of numbers. Now, as to what the sound card actually supports and > what the drivers support, I have no idea. Certainly not being able to > control the volume from the digital jack is not a new thing. I suppose the > mixer controls probably control analog mixers on a sound cards...? If that > is the case, then it explains why control of the digital output level is > generally not found. > > From a practical perspective, your better off to pass the unscaled numbers > to your home theatre receiver. The reason for this is if say you cut the > volume to 1/4 (1/(2^2)) of its maximum in amplitude and you are sticking > with 16 bits of precision then you have lost 2 bits of precision. > > Of course even hearing the difference between 14 and 16 bits is not that > easy, and hearing the difference once you move to 24bits may in fact be > impossible. > > -Robert
digital signals don't contain absolute volume levels, only relative within a dynamic range. You can't do normal volume control for an SPDIF signal. You can do range alterations, but then you loose quality. Steve _______________________________________________ mythtv-users mailing list [email protected] http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
