Which is more accurate: digital or vinyl?

Hi Sam,

This Wikipedia article appears to address your questions much more knowledgeably than I could. Some excerpts:

Because of the nature of sigma-delta converters, one cannot make a direct comparison between DSD and PCM. An approximation is possible, though, and would place DSD in some aspects comparable to a PCM format that has a bit depth of 20 bits and a sampling frequency of 96 kHz.[3] PCM sampled at 24 bits provides a (theoretical) additional 24 dB of dynamic range....

DSD's dynamic range decreases quickly at frequencies over 20 kHz due to the use of strong noise shaping techniques which push the noise out of the audio band resulting in a rising noise floor just above 20 kHz. PCM's dynamic range, on the other hand, is the same at all frequencies. (Some high-end SACD players employ an optional low-pass filter set at 30 kHz for compatibility and safety reasons, suitable for situations where amplifiers or loudspeakers cannot deliver an undistorted output if noise above 30 kHz is present in the signal)....

The Korg MR-1000 1-bit digital recorder samples at 5.6 MHz, twice the SACD rate. It's also referred to as DSD128 because of the sample rate 128x that of CD....

There has been much controversy between proponents of DSD and PCM over which encoding system is superior.

Best regards,
-- Al

11-08-11: Almarg
The difference in db between the maximum possible value as represented digitally (65,535 as expressed in decimal form) and one "level" less than that ... is:

20log(65535/65534) = 0.000132 db

A slight correction to this statement in my earlier post. Since a sign bit is involved, which defines + or -, the range of possible values expressed in decimal form is -32,768 to + 31,767. So the quoted equation should be:

20log(31767/31766) = 0.000273 db

Regards,
-- Al

The how we actually hear stuff is fine but I don't see how what you say applies to analog only. Both analog and digital are shooting for similar results as best I can tell and I have heard both do quite well despite the inherent limitations of each.

Mapman, not trying to change the subject, just pointing out that in the development of Redbook, human perceptual issues were largely ignored. To give a little more depth, we humans tend to not make things perfect, try as we might. In the case of digital, there tend to be in-harmonic distortions that are related to the scan frequency rather than harmonically related to the signal like we have in analog systems.

The problem is that the human ear takes higher-ordered content like this and interprets it as brightness. (this significance of this is that when you measure the digital system on the bench, it will appear to be ruler-flat in frequency response- it is our human perceptual rules that assign the brightness.) Had this problem been addressed properly from the get-go, I suspect that about 90% of the D vs A debate in the last 30 years simply would not have occurred.

This is an issue that has nothing to do with the misapplication of Nyquist, BTW. Now I have been accused of many things over the years, bias being one of them, but in this matter of digital, all I can say is I would really like it to work! I would much prefer to not have to provide space for all the vinyl I own, to fit it on a RAID array would be awesome! But my system is too revealing and the failings of digital are very obvious on it. Mind you, I've done no 'tuning' or 'voicing' or any particular treatments to somehow favor analog over digital. And I can put on a Redbook CD and enjoy it, but even my girlfriend who has no interest in audio at all comments on the obvious improvement that vinyl demonstrates over digital. I think too many people have not been exposed to decent analog playback (for example, improper setup of the equalization circuits in a phono preamp can exacerbate ticks and pops) and so the debate rages.

"Had this problem been addressed properly from the get-go, I suspect that about 90% of the D vs A debate in the last 30 years simply would not have occurred. "

Would would constitute addressing it properly?

I do not hear the brightness you refer to categorically associated with CD or digital in most of my CDs compared to vinyl or other references I have heard. So my ears tell me that there is no redbook plague associated with the format that makes it incompatible to human ears (which I understand are not ruler flat in response, so what, we hear everything the same be it coming out of a stereo or real). I do understand though that it can be a common plague with many CD rigs and has been in mine as well in the past. But I do not understand how the format itself or even being digital precludes this.

I listen to CDs with Class D amps that use negative feedback and still have no issues I can go as loud as I want with my rig with little to no fatigue or brightness. So my experience does not correspond to what you are saying.

I will not question that digital and SS amps with negative feedback in practice have been more plagued by this. Only that it is not inherent to teh technologies categorically, end of story. It can be done extremely well in either format. I do suspect though that R2R is in another league though, for whatever that is worth practically to most.

Thanks, Al :-)

Vbr,
Sam