 
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
|
|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
129.244.120.97
In Reply to: Still off base.... posted by Commuteman on September 26, 2005 at 14:21:41:
You are right, if music input devices (microphones, musical instruments outputs, etc) has significant energy above 20KHZ. My understanding is that microphones roll of very steeply after 20 KHZ ,and in some cases even before.
Also, musical instruments don't output muchbeyond 20KHz. THis obviates the need for a very steep filter.This is what makes redbook CD practical and audibly indistinguishable (at least from a published study scientific perspective) from SACD, DSD or DVD-A.
BTW, since this is a vinyl forum, i'd like to get back to point.
Are you saying that your arguments in the earlier posts show that redbook CD is an INFERIOR medium for encoding the analog signal, as opposed to vinyl grooves? That the analog filters used audibly affect the encoding? for humans?
ML
Follow Ups:
It doesn't really matter if there is or isn't any signal above 20kHz.You can't implement a 22kHz filter (needed for anti-aliasing) that doesn't effect frequencies much lower than that. It's one of those weird conceptual things, but even a 100kHz filter will have an effect way down at 20kHz (although it's small).
I can recommend some things to read if you would like to learn more abou analog filters.
To answer your last question: I believe that there is some digital encoding/decoding scheme that will beat vinyl in its traditional areas of strength, while building on CD's strengths, but 44.1/16 isn't it.
Based on my experience and reading, it appears to be somewhere up above 96/24......
I'm not anti-digital, but it's clear that "perfect sound forever" was a marketing lie. We just aren't there yet.
Peter
OK. THanks.
I disagree with you about the vinyl groove encoding scheme being superior to redbook, becuase, based on my understanding, vinyl groove encoding has much more distortion of the original waveform ( i remember reading somewhere it was 3-4%).
Hence my conclusion, that while vinyl lovers may LIKE this, it's certaily inferior to redbook.
AS i have said before, I like SET amps, but I accept that they suck performance wise.
Anyways, thanks for your posts. I actually learned something, which is very very rare on the asylum.
ML
Two thoughts about your distortion comment:
(I'm not arguing for the sake of it; it's a fascinating subject)Don't downplay your love of SETs; they might actually be technically superior... :-)
Vinyl's distortion characteristic is indeed similar to the SET in 2 important respects. First, the distortion tends to be dominated by low order harmonics, which are less audible than the high order distortion generated by amps that use feedback. Did you know that several percent of 2nd harmonic is virutally inaudible, while 1 percent 7th harmonic would sound terrible?
Secondly, I would guess that the distortion decreases with signal level, so low-level musical details might actually be reproduced with v.v.v low distortion.
Think about digital; it's the opposite. A digital system has the lowest distotion at maximum output. As the level goes down, the number of bits available also decreases, so the distortion goes up.
That COULD mean that low-level musical details are actually reproduced with v.v. HIGH distortion.
So, you see that this is an interesting technical onion that has layers of subtlety. Simplistic statements of clear superiority for digital are pretty risky...
Peter
> > > Think about digital; it's the opposite. A digital system has the lowest distotion at maximum output.
> > > As the level goes down, the number of bits available also decreases, so the distortion goes up.While this is true, distortion of any kind on –60-dB test signals for 16/44 digital is no higher than 0.15%. Furthermore, we now have high-resolution digital with 24-bit quantization. If musical peaks equal 24-bits, -60-dB must equal 14-bits. At 14-bits on a 24-Bit system, distortion of any kind will not exceed 0.015%
On the other hand, the only test that matters is listening. If you have a digital recorder of reasonably high quality and you copy an LP, I don’t think you’ll be able to tell the difference between the digital copy and the LP.
Best regards,
John Elison
Just realized there was one important typo...corrected in bold
First, though: remember that I am not anti-digital; I was simply responding to a massive over-simplification re the capabilities of 44.1/16. In one of the posts on this thread I did state that I thought something like 24-bit > 92kHz digital should be able to do everything vinyl can do....That said, I find it fascinating that so many people have reported better sound from CD copies of LP than from commercial CDs . One possibility is that the process of creating a commercial CD involves manipulation that creates the "CD signature", as opposed to the inherent AD-DA process itself.
I have tried a few experiments using my Meridian processor that digitizes all incoming signals for processing and then recreates analog for output. Matching levels as closely as possible, I find that the feed that has been through AD-DA conversion is very slightly drier and flatter than the original. Less sense of space and reverb. Obviously, since this was not double-blind testing it's not proof of anything at all......
So, back to the distortion question....
Isn't -60dB roughly 10 bits down? That leaves 6 bits, right? 64 possible levels....
I haven't tried looking at the distortion spectrum of a digital signal at this level, but I suspect it's pretty ugly, and composed of lots of high-order harmonics. (Unfortunately, my spectrum analyzer is in storage for another 6 months or so due to remodeling, so I can't try it right now..)
I wonder what the distortion spectrum of your AT OC-9 would look like at an equivalent level? It's quite possible it's THD is WAY lower than 0.15%, and dominated by low order harmonics.
At these levels, my money is on vinyl for lower distortion. The real question is how musically relevant this is....
Interesting discussion!
Peter
"One possibility is that the process of creating a commercial CD involves manipulation that creates the "CD signature", "Actually it is the other way around: the process of creating a commercial LP involves manipulation that creates the "LP signature", whereas the CD is / can be a closer copy of the 2-track pre-master.
Of course, nobody said that the LP and its limitations doesn't lead to a style of mastering that ultimately better suits the majority of domestic replay conditions (system, room, allowable levels).
Hi Peter,I have an interesting comparison for you to look at. Below are two spectrums, one from the OC0ML/II playing the lowest level 1000-Hz sine wave I could find on a test record, compared to a –60-dB signal from a Denon test CD. The interesting thing is that they are directly comparable because I have chosen a zero-dB reference for vinyl at the +18-dB level of the torture track on the Hi-Fi News test record. There are very few records that exceed that level, so I think it represents a good full-scale reference for vinyl. The nice thing about this level is that it falls exactly at –15-dB on the spectrum just like zero-dB full-scale for digital. Therefore, if you accept this level as full-scale for vinyl, you can compare the two graphs directly.
One interesting thing to note is the excessive noise floor for vinyl that rises in the low frequencies due to RIAA playback equalization and arm/cartridge resonance. There might even be some turntable rumble involved, too, although I hope not. I have serious doubts that you would be able to hear anything below this noise because the spectrum analyzer cannot even identify anything.
Another thing to note is that although the harmonic distortion is lower on vinyl for the –35-dB sine wave compared to that for the digital –60-dB sine wave, the actual level of harmonics in the digital graph are lower than those in the vinyl graph.
You really need to put a stop to ignorant beleif that there is no audio beyond 20k or 22k or what ever. That discussion has been brought up and determined years ago. There IS audio way to to 50k. Ask any audio manufacturer of amps or cartridges. The idea that humans cannot hear beyond what every range your fixated on isnt the issue. Sound in those upper frequencies color and shape the sound at lower frequencies.That is a fact and verifiable to test. And has been done many times.
Its been painfull to hear the unwashed masses brainwashed by the redbook cd lies over the years.
*Analog fans may be blind-but digital fans are deaf*
http://www.flickr.com/photos/82495693@N00/
...that vinyl 2nd harmonic distortion from a 10-kHz fundamental exceeds 10%? Can you hear this terrible distortion that I can measure very easily at 20-kHz?Just curious!
Thanks,
John Elison
THanks John for adding your comments. So it seems that people who like vinyl LIKE the imperfections, which was the original comment that started this sub-thread. But to not admit it is imperfect is intellectually dishonest. Of course, we can argue about how we define "better" (is it something we LIKE better or something that is truer to the original signal) but that's another story.
ML
Its a fact there is audio over 20k. Its a fact there is audio at 50k. The original question was weither someone can hear past 20k'ish
Audio is not 1's and 0's its not yes or no. Its fluid sound that 16 bits cannot possible recreate 100% completely. What the digital poeple keep telling themselves is its enough for them.I can hear a CD player playing within 10 seconds just walking by a demo room at an audio shop. (not newer rock/pop stuff thou. Thats garbage to begin with)
*Analog fans may be blind-but digital fans are deaf*
http://www.flickr.com/photos/82495693@N00/
Or else you have never recorded vinyl on a high quality CD recorder.Perhaps you've never heard a CD played on a decent CD player.
Oh, well!
NT
*Analog fans may be blind-but digital fans are deaf*
http://www.flickr.com/photos/82495693@N00/
It takes a lot of second order distortion to be heard; I seem to recall that the threshold is something like 2-3%.Of course 10% should be audible, or at least it will have an effect of some kind.....
Peter
> > > Of course 10% should be audible, or at least it will have an effect of some kind.....Not if the fundamental is 10-kHz and the 2nd harmonic is at 20-kHz. I really don't think anyone can audibly detect distortion at 20-kHz, which would be 20-dB below the fundamental. Of course, I could be wrong.
Anyway, that’s why I think that vinyl doesn’t sound so bad. Its greatest distortion is at high frequencies leaving only 1% to 3% at low frequencies.
Best regards,
John Elison
He's clueless re harmonics of fundamental frequencies for starters.
HenryNecessity is a mother . . .
This post is made possible by the generous support of people like you and our sponsors:
Top of Page ]
[ Contact Us ]
[ Support/Wish List ]
[ Copyright © 2025, Audio Asylum, all rights reserved ]
