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

---

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

---

[ Alert Moderator ]

---

Re: Dave, Jitter would be an issue out of the transport...

Posted by Dave Kingsland on September 20, 2005 at 17:43:29

In Reply to: Dave, Jitter would be an issue out of the transport... posted by Michi on September 19, 2005 at 22:04:01:

...if the transport simply read raw DSD "come what may". It doesn't do that in SACD. You may assume that DSD would be more prone to jitter, but the blocks are read *data wise* as decoded chunks in SACD, with a checksum: either they decoded properly or they didnt.

Remember, the content of the data is not important. Jitter is just a modulation of the clock signal.

On a redbook transport, you're essentially just feeding an EFM encoded PCM stream into a dac. If there's jitter on the disc, that reaches the dac.

Well, there is always a minimal buffer involved, required for Redbook error correction. The problem with cheap Redbook transports is that the buffer is driven by a clock derived from the signal read from the disc. To reduce the jitter, you need something like a FIFO buffer with different clocks on the input and output, which isn't cheap. Even then, some of the input clock jitter gets passed through to the output clock through whatever PLL circuit is used to synchronize them.

With SACD, jitter does not become an issue until it has been decoded to raw DSD; it can happen between say, a Furore chip and a PCM1792, but not between the transport and the Furore; that data is read in a block/CRC manner where the data will not even be unpacked unless the block is valid.

Again, jitter and data errors are different things. You may be able to read the data correctly 100 out of 100 times, but the clock at the output of the transport will have jitter every time. Jitter is an issue for every clock in the system and can be passed from one clock to another because you can never completely isolate them. Even a highly jitter immune design like the Benchmark DAC1 passes some of the input jitter through. I would expect that SACD and DVD players vary significantly in the amount of jitter they pass through to the output based on how their various clocks are derived and how much attention the designers pay to isolating the clocks.

Tell me, could ShineOla, in your opinion, effect the clarity of a JPEG read off of a DVD-ROM? If not, why not? And why is this situation any different than one block of DST-packed DSD data?

I have no idea whether ShineOla has any effect at all, and I haven't tried it. However, if it did have an effect, it would likely be a change in the jitter coming out of the transport, because unless the disc is damaged, data errors are unlikely. The clarity of the JPEG in your example is a function of the integrity of the data, not the jitter. The jitter won't change the bits in the block of DSD data, but it will produce distortion in the analog output of the player.

Dave

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

VH Audio

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2025, Audio Asylum, all rights reserved ]

---

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

---