Hi-Rez Highway New high resolution SACD releases, players and technology.

---

[ Follow Ups ] [ Post Followup ] Thread: [ Display  All  Email ] [ Hi-Rez Highway ]

---

[ Alert Moderator ]

---

Nice, but no cigar

Posted by Tony Lauck (A) on December 18, 2008 at 18:15:02

In Reply to: RE: Liberating DSD - already done posted by Christine Tham on December 18, 2008 at 17:14:15:

The link you gave us is bad. A file downloads, but it isn't a valid zip file and won't open. I had found this file yesterday, but I didn't post it, because it didn't work.

I don't believe the general gist of how I described converting delta sigma to DSD is incorrect. However, if I missed something, please let me know. You could provide the Excel program if you still have it.

I was describing conversion of one bit delta sigma, which is what DSD is. DSD to PCM is conceptually similar to converting DSD to analog and converting the result back to digital, except that the analog domain is avoided. Filtering is required for two reasons, to smooth the DSD bitstream and to remove any frequencies above the Nyquist limit, enabling decimation without aliasing. The details of the filtering, like the filtering on all sample rate converters, will be a compromise between different factors, and so designers may want to try and keep their filter designs proprietary (e.g. the coefficients). However, when downconverting from DSD to 176.4 PCM filtering is not likely to be at all critical sonically.

Earlier converters from DSD to PCM didn't do any serious filtering, they just used counters. This will work, but won't be as good as a better filtering approach. However, logic is much cheaper than it was 20 years ago, so this wouldn't be a likely approach for a quality audio part. It might still be used for telephone codecs.




Tony Lauck

"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar

• http://www.beis.de/Elektronik/DeltaSigma/DeltaSigma.html   (Open in New Window)

This post is made possible by the generous support of people like you and our sponsors:

Crux Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---