On Mon, Mar 14, 2005 at 10:13:59PM +0200, Jussi Laako wrote: > See http://www.cirrus.com/en/images/product_diagrams/4398blkdiag_mag.gif > and "Direct DSD" path. Which one of the paths, the "Direct DSD" or the > "PCM" you think is easier and cheaper to make good quality?
This confirms that you can't even have a digital volume control without going back to some form of pseudo-PCM. How do you control volume on your all digital DSD-to-PWM amplifier ? The 'pure DSD' way of course can be quite simple, but with all the limitations that simplicity brings along. For example, high quality surround should use a format that is independent of speaker layout (such as Ambisonics), and have the decoding done in the player, using information about the listener's speaker setup. Just to do this, DSD would have to be recoded to PCM (unless you do it in the analog domain). Just from the practical side, distributng audio in PCM format is much more flexible. As to pure quality, DSD has an incredible resolution at low frequencies, but that goes down rapidly as frequency rises. With PCM you get the same resolution over the entire frequency range. And with 24 bits, you have a coding space that is much bigger than what your ears are capable of decoding. -- FA
