Hi rez and Solid State Noise

*Scotty* · « **Reply #20 on:** 3 Nov 2010, 04:10 pm »

I don't see the dynamic range of Redbook being all that superior to that of vinyl.
Both have about 60dB of usable dynamic range. The Redbook 16bit depth gives us a pretty grim rise in THD after -60dB.
Scotty

martyo · « **Reply #21 on:** 3 Nov 2010, 04:34 pm »

Quote from: *Scotty* on 3 Nov 2010, 04:10 pm

I don't see the dynamic range of Redbook being all that superior to that of vinyl.
Both have about 60dB of usable dynamic range. The Redbook 16bit depth gives us a pretty grim rise in THD after -60dB.
Scotty

Really?

*Scotty* · « **Reply #22 on:** 3 Nov 2010, 05:46 pm »

Yes. In a digital recording system you have less bits to describe the waveform as the signal level decreases which results in increasing distortion. A worst case example is the 16bit system -90 waveform with only three DC voltage levels available the describe the waveform.

When you hit the -60 signal level you don't magically have .0015%THD it is about 3% THD.
Scotty

martyo · « **Reply #23 on:** 3 Nov 2010, 06:07 pm »

Thanks *Scotty*

turkey · « **Reply #24 on:** 3 Nov 2010, 06:38 pm »

And that's why we have dither.

http://www.hifi-writer.com/he/dvdaudio/dither.htm

*Scotty* · « **Reply #25 on:** 3 Nov 2010, 07:27 pm »

While link to the article on dithering makes for interesting reading it does not invalidate my observations concerning the distortion problems of the 16 bit format.
This picture says it all

Remember that's supposed to be a 980Hz sine wave. The picture is a textbook illustration of distortion. It will be easier on the ears than the undithered -60 waveform but there is no way this can be considered acceptable performance from a distortion standpoint.
This is why we have a 24 bit format. Here is an undithered -90 sine wave.

Scotty

turkey · « **Reply #26 on:** 3 Nov 2010, 07:49 pm »

Quote from: *Scotty* on 3 Nov 2010, 07:27 pm

Remember that's supposed to be a 980Hz sine wave. The picture is a textbook illustration of distortion. It will be easier on the ears than the undithered -60 waveform but there is no way this can be considered acceptable performance from a distortion standpoint.

But the THD has dropped below the noise floor and THD was what you were talking about before.

Quote

This is why we have a 24 bit format. Here is an undithered -90 sine wave.

Yet, when controlled tests are done, people can't hear any difference between 16-bit and 24-bit.

sts9fan · « **Reply #27 on:** 3 Nov 2010, 07:59 pm »

Paper Turkey?

srb · « **Reply #28 on:** 3 Nov 2010, 08:13 pm »

Here is one from the Audio Engineering Society:

"Audibility of a CD-Standard A/DA/A Loop Inserted into High-Resolution Audio Playback"

Authors: Meyer, E. Brad; Moran, David R.
Affiliation: Boston Audio Society, Lincoln, MA, USA
JAES Volume 55 Issue 9 pp. 775-779; September 2007
http://www.aes.org/journal/online/comment/?ID=14195

You need to be an AES member to download the paper.

Steve

turkey · « **Reply #29 on:** 3 Nov 2010, 08:15 pm »

http://www.aes.org/e-lib/browse.cfm?elib=14195

turkey · « **Reply #30 on:** 3 Nov 2010, 08:16 pm »

Yeah, what he said.

werd · « **Reply #31 on:** 3 Nov 2010, 08:55 pm »

Quote from: turkey on 3 Nov 2010, 08:15 pm

http://www.aes.org/e-lib/browse.cfm?elib=14195

I cant believe people pay for that crap

konut · « **Reply #32 on:** 3 Nov 2010, 09:45 pm »

Quote from: werd on 3 Nov 2010, 08:55 pm

I cant believe people pay for that crap

Funny, ain't it? I feel the same way about vinyl and tubes. Go figure!

Mitsuman · « **Reply #33 on:** 3 Nov 2010, 10:11 pm »

Quote from: konut on 3 Nov 2010, 09:45 pm

Funny, ain't it? I feel the same way about vinyl and tubes. Go figure!

It sure is, cuz I feel the same way about CD and tubes.

*Scotty* · « **Reply #34 on:** 3 Nov 2010, 11:05 pm »

I think there probably a study showing that MP3 is indistinguishable from Redbook.
If you set your standards low enough a wax cylinder and a thorn to play it with will get you by.
If one believes that there is no progress left to be made and the status quo as good enough for you that's fine. I'll take the higher resolution format when it becomes available.

Scotty

guest1632 · « **Reply #35 on:** 6 Nov 2010, 05:58 am »

Quote from: turkey on 3 Nov 2010, 01:39 pm

My point was that Redbook allows for better dynamic range and S/N than we can actually use, so why spend more money on a 144 dB S/N? If you'd like to avoid mentioning Redbook, we could observe that many people are happy with the dynamic range and S/N that vinyl allows. (I'm not, which is why I use Redbook as my reference.)

Hi, Well, I defy you to hear 110DB down. There are times where I think measurement is stressed to much. Sure, the idea of obtaining a perfect waveform is something to be desired, but we don't obviously have the technology yet. There's more than just low noise here. Like has been pointed out, a typical Phono amp is 85DB and that works just fine. I think if you are really bent on low noise especially for an amplifier, then you will have to wait for technology to catch up with quieter SS gear. If you can again, hear 110DB down, then you for sure have sharp ears. I sure wish someone would work on quieter phono sections, like 100DB down. Now that would be a real accomplishment.

Ray