Posted November 20 2002 - 10:58 AM
Jagan asked Lee:
| I understand why Class B amplifiers have some zero-crossing distortion, but why would PCM have it? |
Lee told Jagan:
| Check Ed Meitner's interview on Positive Feedback. It has to do with error rates when PCM resets the bits to zero. |
Jagan checked out
the Ed Meitner interview
, and has some comments on the zero-crossing distortion comments.
Ed Meitner said
| Imagine what happens at your zero crossing. You have all those bits flipping. You have, you know, noise shock in the system coming off the power supply if all of a sudden 23 bits change from all zeros to all ones. You have that at every zero crossing. |
Wait a second. It's not like turning on 23 bits at the microelectronics level is like throwing 23 Frankenstein switches and taking down the power grid! Ed Meitner, however, is right that 1-bit converters don't have that
problem. 1-bit converters, for the record, can exhibit limit-cycle tones at zero-levels as well as generate high-frequency switching noise.
Just like the high-frequency switching noise can be filtered off, decoupling capacitors and proper power supply design can filter out power sags due to PCM numeric rollovers. Determining which technology's situation is worse depends largely on the implementation of the technology.
Then again, selective memory may be at work with Ed since he said earlier in the interview:
| And don’t forget that every A to D converter that you see on the market today starts off as a DSD modulator. So then you have the DSD signal on the A to D that just goes to the PCM down sampler or decimator and gets turned into PCM, so the life of the audio in the digital world really starts off as a one-bit signal. |
Posted November 20 2002 - 01:13 PM
| The major problem I see is naming the Stones disc as watershed SACD discs |
Oh come on. There is a picture of the Stones SACD next to the word "Watershed" in the dictionary. It created tons of excitement and grass roots appeal and sold well as a catalog remaster. A complete home run. And Clear Channel promoted the hell out of Super Audio on the remasters at hundreds of radio stations.
| Cymbals sound fine to me on DVD-A though. |
I strongly feel that even in DVDA, cymbals sound too harsh and metallic and with not enough shimmer. And I hear this in the studio and on $100K stereo systems.
Viewing: Sony KDSXBR150, Sony Bluray S570, ATT Uverse
Listening: Sony SCD777ES, Benchmark DAC1Pre, VPI/Modwright SWP9SE/Lyra Argo, Audio Research Ref3/VT100, Maggie 1.7s
Posted November 21 2002 - 12:56 AM
| These discs were destined to sell well, SACD or not. Look at the popularity and hype surrounding Forty Licks, which is not a hybrid SACD. The Stones are hugely popular. So is the CD format. |
I do agree these hybrids would have done well regardless, but the reason I feel it is a watershed event is that Super Audio was widely promoted across many radio stations and gathered lots of mention, all positive based on my reading cept for the negative CNN wire story about copyright protection, in the mainstream press. It also made a big splash in high end journals and more importantly the hardcore music magazines like Rolling Stone, Spin, ICE, etc.
| The Sony diagram for DSD is about as accurate as this traceroute diagram for the path I take to get to the Home Theater Forum Web Server: |
John, it is insulting for you to compare my diagram to this one. There is no connection at all and the Sony diagram is much more detailed.
Look. I did what I could to explain DSD to a group of engineers and non-engineers in ONE PAGE. I am proud of my work in the Technical piece. There was not time to write an AES piece though I can refer you to several.
Maybe the question we should ask is why Widescreen Review has not done a detailed comparison? That would be valuable for your readers. As I have offered before, I would be happy to help out there and could bring in some good references.
| If you want to puff your chest up about those $100K stereo systems that's fine. |
This is also unfair as I am not bragging about listening to $100K systems. That is fairly routine in the circles I travel in given my work with Chesky and the large number of audiophiles I know around the country.
I was simply saying that my opinion is that 24/96 does not adequately reproduce the cymbals properly on even very high resolution systems.
If I feel there is one benefit that working on some many music projects has afforded me is the right to express my opinion on sound quality.
I was hoping that I could present my findings on the two new audio formats and we could then use this discussion to go into more detail on each point and debate in a logical fashion. These personal attacks do not add any value to the HTF.
Let's put aside our personal differences and focus on the facts and clearly marked opinions as I tried to present them in the documents.